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tinybasic / data /Basic2 /IoTBasic /IoTBasic.ino
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introvoyz041
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 /*----------------------------------------------------------------
Please read this before compiling the code.
- Review hardware.h for settings specific hardware settings.
Super important on Arduino and Raspberry PI.
- language.h controls the language features.
A heuristic is used to compile the language features if
not defined explicitly in language.h.
-----------------------------------------------------------------
Stefan's IoT BASIC interpreter - BASIC for everywhere.
See the licence file on
https://github.com/slviajero/tinybasic for copyright/left.
(GNU GENERAL PUBLIC LICENSE, Version 3, 29 June 2007)
Author: Stefan Lenz, sl001@serverfabrik.de
Currently there are two versions of the runtime environment.
One contains all platforms compiled in the Arduino IDE
(ESP8266, ESP32, AVR, MEGAAVR, SAM*, RP2040, STM*,
XMC*, NRENESA, Arduino GIGA).
Anothers contains all platforms compiled in gcc with a POSIX OS
(Mac, Raspberry, Windows/MINGW) plus rudimentary MSDOS with tc2.0. The
latter will be removed soon.
The interface to BASIC is identical.
*/
/* the runtime environment */
#include "hardware.h"
#include "runtime.h"
/*
* the core basic language headers
*/
#include "language.h"
#include "basic.h"
/* use long jump for error handling */
#if USELONGJUMP == 1
#include "setjmp.h"
#endif
/* Global BASIC definitions */
/*
All BASIC keywords for the tokens, PROGMEM on Arduino
Normal memory elsewhere.
*/
const char sge[] PROGMEM = "=>";
const char sle[] PROGMEM = "<=";
const char sne[] PROGMEM = "<>";
/* Palo Alto language set */
const char sprint[] PROGMEM = "PRINT";
const char slet[] PROGMEM = "LET";
const char sinput[] PROGMEM = "INPUT";
const char sgoto[] PROGMEM = "GOTO";
const char sgosub[] PROGMEM = "GOSUB";
const char sreturn[] PROGMEM = "RETURN";
const char sif[] PROGMEM = "IF";
const char sfor[] PROGMEM = "FOR";
const char sto[] PROGMEM = "TO";
const char sstep[] PROGMEM = "STEP";
const char snext[] PROGMEM = "NEXT";
const char sstop[] PROGMEM = "STOP";
const char slist[] PROGMEM = "LIST";
const char snew[] PROGMEM = "NEW";
const char srun[] PROGMEM = "RUN";
const char sabs[] PROGMEM = "ABS";
const char srnd[] PROGMEM = "RND";
const char ssize[] PROGMEM = "SIZE";
const char srem[] PROGMEM = "REM";
/* Apple 1 language set */
#ifdef HASAPPLE1
const char snot[] PROGMEM = "NOT";
const char sand[] PROGMEM = "AND";
const char sor[] PROGMEM = "OR";
const char slen[] PROGMEM = "LEN";
const char ssgn[] PROGMEM = "SGN";
const char speek[] PROGMEM = "PEEK";
const char sdim[] PROGMEM = "DIM";
const char sclr[] PROGMEM = "CLR";
const char shimem[] PROGMEM = "HIMEM";
const char stab[] PROGMEM = "TAB";
const char sthen[] PROGMEM = "THEN";
const char sbend[] PROGMEM = "END";
const char spoke[] PROGMEM = "POKE";
#endif
/* Stefan's basic additions */
#ifdef HASSTEFANSEXT
const char scont[] PROGMEM = "CONT";
const char ssqr[] PROGMEM = "SQR";
const char spow[] PROGMEM = "POW";
const char smap[] PROGMEM = "MAP";
const char sdump[] PROGMEM = "DUMP";
const char sbreak[] PROGMEM = "BREAK";
#endif
/* LOAD and SAVE is always there */
const char ssave[] PROGMEM = "SAVE";
const char sload[] PROGMEM = "LOAD";
#ifdef HASSTEFANSEXT
const char sget[] PROGMEM = "GET";
const char sput[] PROGMEM = "PUT";
const char sset[] PROGMEM = "SET";
const char scls[] PROGMEM = "CLS";
const char slocate[] PROGMEM = "LOCATE";
const char selse[] PROGMEM = "ELSE";
#endif
/* Arduino functions */
#ifdef HASARDUINOIO
const char spinm[] PROGMEM = "PINM";
const char sdwrite[] PROGMEM = "DWRITE";
const char sdread[] PROGMEM = "DREAD";
const char sawrite[] PROGMEM = "AWRITE";
const char saread[] PROGMEM = "AREAD";
const char sdelay[] PROGMEM = "DELAY";
const char smillis[] PROGMEM = "MILLIS";
const char sazero[] PROGMEM = "AZERO";
const char sled[] PROGMEM = "LED";
#endif
#ifdef HASTONE
const char stone[] PROGMEM = "PLAY";
#endif
#ifdef HASPULSE
const char spulse[] PROGMEM = "PULSE";
#endif
/* DOS functions */
#ifdef HASFILEIO
const char scatalog[] PROGMEM = "CATALOG";
const char sdelete[] PROGMEM = "DELETE";
const char sfopen[] PROGMEM = "OPEN";
const char sfclose[] PROGMEM = "CLOSE";
const char sfdisk[] PROGMEM = "FDISK";
#endif
/* low level access functions */
#ifdef HASUSRCALL
const char susr[] PROGMEM = "USR";
const char scall[] PROGMEM = "CALL";
#endif
/* mathematics */
#ifdef HASFLOAT
const char ssin[] PROGMEM = "SIN";
const char scos[] PROGMEM = "COS";
const char stan[] PROGMEM = "TAN";
const char satan[] PROGMEM = "ATAN";
const char slog[] PROGMEM = "LOG";
const char sexp[] PROGMEM = "EXP";
#endif
/* INT is always needed to make float/int programs compatible */
const char sint[] PROGMEM = "INT";
/* elemetars graphics */
#ifdef HASGRAPH
const char scolor[] PROGMEM = "COLOR";
const char splot[] PROGMEM = "PLOT";
const char sline[] PROGMEM = "LINE";
const char scircle[] PROGMEM = "CIRCLE";
const char srect[] PROGMEM = "RECT";
const char sfcircle[] PROGMEM = "FCIRCLE";
const char sfrect[] PROGMEM = "FRECT";
#endif
/* Dartmouth BASIC extensions */
#ifdef HASDARTMOUTH
const char sdata[] PROGMEM = "DATA";
const char sread[] PROGMEM = "READ";
const char srestore[] PROGMEM = "RESTORE";
const char sdef[] PROGMEM = "DEF";
const char sfn[] PROGMEM = "FN";
const char son[] PROGMEM = "ON";
#endif
/* The Darkarts commands */
#ifdef HASDARKARTS
const char smalloc[] PROGMEM = "MALLOC";
const char sfind[] PROGMEM = "FIND";
const char seval[] PROGMEM = "EVAL";
#endif
/* complex error handling */
#ifdef HASERRORHANDLING
const char serror[] PROGMEM = "ERROR";
#endif
/* iot extensions */
#ifdef HASIOT
const char savail[] PROGMEM = "AVAIL";
const char sstr[] PROGMEM = "STR";
const char sinstr[] PROGMEM = "INSTR";
const char sval[] PROGMEM = "VAL";
const char snetstat[] PROGMEM = "NETSTAT";
const char ssensor[] PROGMEM = "SENSOR";
const char swire[] PROGMEM = "WIRE";
const char ssleep[] PROGMEM = "SLEEP";
#endif
/* events and interrupts */
#ifdef HASTIMER
const char safter[] PROGMEM = "AFTER";
const char severy[] PROGMEM = "EVERY";
#endif
#ifdef HASEVENTS
const char sevent[] PROGMEM = "EVENT";
#endif
#ifdef HASSTRUCT
const char swhile[] PROGMEM = "WHILE";
const char swend[] PROGMEM = "WEND";
const char srepeat[] PROGMEM = "REPEAT";
const char suntil[] PROGMEM = "UNTIL";
const char sswitch[] PROGMEM = "SWITCH";
const char scase[] PROGMEM = "CASE";
const char sswend[] PROGMEM = "SWEND";
const char sdo[] PROGMEM = "DO";
const char sdend[] PROGMEM = "DEND";
#endif
#ifdef HASDARTMOUTH
#ifdef HASMULTILINEFUNCTIONS
const char sfend[] PROGMEM = "FEND";
#endif
#endif
#ifdef HASMSSTRINGS
const char sasc[] PROGMEM = "ASC";
const char schr[] PROGMEM = "CHR";
const char sright[] PROGMEM = "RIGHT";
const char sleft[] PROGMEM = "LEFT";
const char smid[] PROGMEM = "MID";
const char sspc[] PROGMEM = "SPC";
#endif
#ifdef HASEDITOR
const char sedit[] PROGMEM = "EDIT";
#endif
#ifdef HASHELP
const char shelp[] PROGMEM = "HELP";
#endif
/* was BITWISE, now always there because really important */
const char sshl[] PROGMEM = "<<";
const char sshr[] PROGMEM = ">>";
const char sbit[] PROGMEM = "BIT";
/* zero terminated keyword storage */
const char* const keyword[] PROGMEM = {
sge, sle, sne, sprint, slet, sinput,
sgoto, sgosub, sreturn, sif, sfor, sto,
sstep, snext, sstop, slist, snew, srun,
sabs, srnd, ssize, srem,
#ifdef HASAPPLE1
snot, sand, sor, slen, ssgn, speek, sdim,
sclr, shimem, stab, sthen,
sbend, spoke,
#endif
#ifdef HASSTEFANSEXT
scont, ssqr, spow, smap, sdump, sbreak,
#endif
ssave, sload,
#ifdef HASSTEFANSEXT
sget, sput, sset, scls, slocate, selse,
#endif
#ifdef HASARDUINOIO
spinm, sdwrite, sdread, sawrite, saread,
sdelay, smillis, sazero, sled,
#endif
#ifdef HASTONE
stone,
#endif
#ifdef HASPULSE
spulse,
#endif
#ifdef HASFILEIO
scatalog, sdelete, sfopen, sfclose, sfdisk,
#endif
#ifdef HASUSRCALL
susr, scall,
#endif
#ifdef HASFLOAT
ssin, scos, stan, satan, slog, sexp,
#endif
sint,
#ifdef HASGRAPH
scolor, splot, sline, scircle, srect,
sfcircle, sfrect,
#endif
#ifdef HASDARTMOUTH
sdata, sread, srestore, sdef, sfn, son,
#endif
#ifdef HASDARKARTS
smalloc, sfind, seval,
#endif
/* complex error handling */
#ifdef HASERRORHANDLING
serror,
#endif
#ifdef HASIOT
savail, sstr, sinstr, sval,
snetstat, ssensor, swire, ssleep,
#endif
#ifdef HASTIMER
safter, severy,
#endif
#ifdef HASEVENTS
sevent,
#endif
#ifdef HASSTRUCT
swhile, swend, srepeat, suntil, sswitch, scase, sswend,
sdo, sdend,
#endif
#ifdef HASDARTMOUTH
#ifdef HASMULTILINEFUNCTIONS
sfend,
#endif
#endif
#ifdef HASMSSTRINGS
sasc, schr, sright, sleft, smid, sspc,
#endif
#ifdef HASEDITOR
sedit,
#endif
#ifdef HASHELP
shelp,
#endif
sshl, sshr, sbit,
0
};
/* the zero terminated token dictonary needed for scalability */
const token_t tokens[] PROGMEM = {
GREATEREQUAL, LESSEREQUAL, NOTEQUAL, TPRINT, TLET,
TINPUT, TGOTO, TGOSUB, TRETURN, TIF, TFOR, TTO, TSTEP,
TNEXT, TSTOP, TLIST, TNEW, TRUN, TABS, TRND, TSIZE, TREM,
#ifdef HASAPPLE1
TNOT, TAND, TOR, TLEN, TSGN, TPEEK, TDIM, TCLR,
THIMEM, TTAB, TTHEN, TEND, TPOKE,
#endif
#ifdef HASSTEFANSEXT
TCONT, TSQR, TPOW, TMAP, TDUMP, TBREAK,
#endif
TSAVE, TLOAD,
#ifdef HASSTEFANSEXT
TGET, TPUT, TSET, TCLS, TLOCATE, TELSE,
#endif
#ifdef HASARDUINOIO
TPINM, TDWRITE, TDREAD, TAWRITE, TAREAD, TDELAY, TMILLIS,
TAZERO, TLED,
#endif
#ifdef HASTONE
TTONE,
#endif
#ifdef HASPULSE
TPULSE,
#endif
#ifdef HASFILEIO
TCATALOG, TDELETE, TOPEN, TCLOSE, TFDISK,
#endif
#ifdef HASSTEFANSEXT
TUSR, TCALL,
#endif
#ifdef HASFLOAT
TSIN, TCOS, TTAN, TATAN, TLOG, TEXP,
#endif
TINT,
#ifdef HASGRAPH
TCOLOR, TPLOT, TLINE, TCIRCLE, TRECT,
TFCIRCLE, TFRECT,
#endif
#ifdef HASDARTMOUTH
TDATA, TREAD, TRESTORE, TDEF, TFN, TON,
#endif
#ifdef HASDARKARTS
TMALLOC, TFIND, TEVAL,
#endif
#ifdef HASERRORHANDLING
TERROR,
#endif
#ifdef HASIOT
TAVAIL, TSTR, TINSTR, TVAL, TNETSTAT,
TSENSOR, TWIRE, TSLEEP,
#endif
#ifdef HASTIMER
TAFTER, TEVERY,
#endif
#ifdef HASEVENTS
TEVENT,
#endif
#ifdef HASSTRUCT
TWHILE, TWEND, TREPEAT, TUNTIL, TSWITCH, TCASE, TSWEND,
TDO, TDEND,
#endif
#ifdef HASDARTMOUTH
#ifdef HASMULTILINEFUNCTIONS
TFEND,
#endif
#endif
#ifdef HASMSSTRINGS
TASC, TCHR, TRIGHT, TLEFT, TMID, TSPC,
#endif
#ifdef HASEDITOR
TEDIT,
#endif
#ifdef HASHELP
THELP,
#endif
TSHL, TSHR, TBIT,
0
};
/* experimental, do not use right now */
const bworkfunction_t workfunctions[] PROGMEM = {
0, 0, 0, xprint, 0
};
/* errors and messages */
const char mfile[] PROGMEM = "file.bas";
const char mprompt[] PROGMEM = "> ";
const char mgreet[] PROGMEM = "Stefan's Basic 2.0";
const char mline[] PROGMEM = "LINE";
const char mnumber[] PROGMEM = "NUMBER";
const char mvariable[] PROGMEM = "VARIABLE";
const char marray[] PROGMEM = "ARRAY";
const char mstring[] PROGMEM = "STRING";
const char mstringv[] PROGMEM = "STRINGVAR";
const char egeneral[] PROGMEM = "Error";
#ifdef HASERRORMSG
const char eunknown[] PROGMEM = "Syntax";
const char enumber[] PROGMEM = "Number";
const char edivide[] PROGMEM = "Div by 0";
const char eline[] PROGMEM = "Unknown Line";
const char emem[] PROGMEM = "Memory";
const char estack[] PROGMEM = "Stack";
const char erange[] PROGMEM = "Range";
const char estring[] PROGMEM = "String";
const char evariable[] PROGMEM = "Variable";
const char eloop[] PROGMEM = "Loop";
const char efile[] PROGMEM = "File";
const char efun[] PROGMEM = "Function";
const char eargs[] PROGMEM = "Args";
const char eeeprom[] PROGMEM = "EEPROM";
const char esdcard[] PROGMEM = "SD card";
#endif
#ifdef HASHELP
#ifdef BASICFULL
const char mbasiclangset[] PROGMEM = "full";
#elif defined(BASICSIMPLE)
const char mbasiclangset[] PROGMEM = "simple with integer";
#elif defined(BASICINTEGER)
const char mbasiclangset[] PROGMEM = "integer";
#elif defined(BASICMINIMAL)
const char mbasiclangset[] PROGMEM = "minimal";
#elif defined(BASICSIMPLEWITHFLOAT)
const char mbasiclangset[] PROGMEM = "simple with float";
#elif defined(BASICTINYWITHFLOAT)
const char mbasiclangset[] PROGMEM = "tiny with float";
#else
const char mbasiclangset[] PROGMEM = "custom";
#endif
const char mlangset[] PROGMEM = "Language set: ";
const char mkeywords[] PROGMEM = "Keywords: ";
#endif
const char* const message[] PROGMEM = {
mfile, mprompt, mgreet,
mline, mnumber, mvariable, marray,
mstring, mstringv,
egeneral
#ifdef HASERRORMSG
, eunknown, enumber, edivide, eline,
emem, estack, erange,
estring, evariable, eloop, efile, efun, eargs,
eeeprom, esdcard
#endif
#ifdef HASHELP
, mbasiclangset, mlangset, mkeywords
#endif
};
/*
maxnum: the maximum accurate(!) integer of a
32 bit float
strindexsize: in the new code this is simply the size of the
stringlength type. Currently only 1 byte and 2 bytes are tested.
*/
#ifdef HASFLOAT
#ifdef HAS64BIT
const number_t maxnum = 9007199254740992;
#else
const number_t maxnum = 16777216;
#endif
#else
const number_t maxnum = (number_t)~((number_t)1 << (sizeof(number_t) * 8 - 1));
#endif
const int numsize = sizeof(number_t);
const int addrsize = sizeof(address_t);
const int eheadersize = sizeof(address_t) + 1;
const int strindexsize = sizeof(stringlength_t); /* default in the meantime, strings up to unsigned 16 bit length */
const address_t maxaddr = (address_t)(~0);
/*
The basic interpreter is implemented as a stack machine
with global variable for the interpreter state, the memory
and the arithmetic during run time.
*/
/* the stack, all BASIC arithmetic is done here */
accu_t stack[STACKSIZE];
address_t sp = 0;
/* a small buffer to process string arguments, mostly used for Arduino PROGMEM and string functions */
/* use with care as it is used in some string functions */
char sbuffer[SBUFSIZE];
/* the input buffer, the lexer can tokenize this and run from it, bi is an index to this.
bi must be global as it is the program cursor in interactive mode */
char ibuffer[BUFSIZE] = "\0";
char *bi;
/* a static array of variables A-Z for the small systems that have no heap */
#ifndef HASAPPLE1
number_t vars[VARSIZE];
#endif
/* the BASIC working memory, either malloced or allocated as a global array */
#if (defined(MEMSIZE) && MEMSIZE != 0)
mem_t mem[MEMSIZE];
#else
mem_t* mem;
#endif
address_t himem, memsize;
/* reimplementation of the loops, will replace the forstack */
bloop_t loopstack[FORDEPTH];
index_t loopsp = 0;
/* the GOSUB stack remembers an address to jump to */
address_t gosubstack[GOSUBDEPTH];
index_t gosubsp = 0;
/* arithmetic accumulators */
number_t x, y;
/* the name of on object, replaced xc and xy in BASIC 1 */
name_t name;
/* an address accumulator, used a lot in string operations */
address_t ax;
/* a string index registers, new style identifying a string either in C memory or BASIC memory */
string_t sr;
/* the active token */
token_t token;
/* the curent error, can be a token, hence token type */
token_t er;
/* the jmp buffer for the error handling */
#if USELONGJUMP == 1
jmp_buf sthook;
#endif
/* a trapable error */
mem_t ert;
/* the interpreter state, interactive, run or run from EEPROM */
mem_t st;
/* the current program location */
address_t here;
/* the topmost byte of a program in memory, beginning of free BASIC RAM */
address_t top;
/* used to format output with # */
mem_t form = 0;
/* do we use the Microsoft convention of an array starting at 0 or 1 like Apple 1
two seperate variables because arraylimit can be changed at runtime for existing arrays
msarraylimit says if an array should be created with n or n+1 elements */
#ifdef MSARRAYLIMITS
mem_t msarraylimits = 1;
address_t arraylimit = 0;
#else
mem_t msarraylimits = 0;
address_t arraylimit = 1;
#endif
/* behaviour around boolean, needed to change the interpreters personality at runtime */
/* -1 is microsoft true while 1 is Apple 1 and C style true. */
mem_t booleanmode = BOOLEANMODE;
/* setting the interpreter to integer at runtime */
mem_t forceint = 0;
/* the default size of a string now as a variable */
stringlength_t defaultstrdim = STRSIZEDEF;
/* the base of the random number generator
0 is Apple 1 style RND from 0 to n-epsilon
1 is Palo Alto style from 1 to n
*/
mem_t randombase = 0;
/* is substring logic used or not */
#ifdef SUPPRESSSUBSTRINGS
mem_t substringmode = 0;
#else
mem_t substringmode = 1;
#endif
/* the flag for true MS tabs */
mem_t reltab = 0;
mem_t dummy;
/* the flag for lower case names */
mem_t lowercasenames = 0;
/* the number of arguments parsed from a command */
mem_t args;
/* the random number seed, this is unsigned */
#ifndef HASFLOAT
address_t rd;
#else
unsigned long rd;
#endif
/* the RUN debuglevel */
mem_t debuglevel = 0;
/* DATA pointer, where is the current READ statement */
#ifdef HASDARTMOUTH
address_t data = 0;
address_t datarc = 1;
#endif
/*
process command line arguments in the POSIX world
bnointafterrun is a flag to remember if called as command
line argument, in this case we don't return to interactive
*/
#ifdef HASARGS
int bargc;
char** bargv;
mem_t bnointafterrun = 0;
#endif
/* formaters lastouttoken and spaceafterkeyword to make a nice LIST */
mem_t lastouttoken;
mem_t spaceafterkeyword;
mem_t outliteral = 0;
mem_t lexliteral = 0;
/*
The cache for the heap search - helps the string code.
The last found object on the heap is remembered. This is needed
because the string code sometime searches the heap twice during the
same operation. Also, bfind is used to remember the length of the
last found object.
*/
#ifdef HASAPPLE1
heap_t bfind_object;
#endif
/*
a variable for string to numerical conversion,
telling you were the number ended.
*/
address_t vlength;
/* the timer code - very simple needs to be converted to to a struct */
/* timer type */
#ifdef HASTIMER
btimer_t after_timer = {0, 0, 0, 0, 0};
btimer_t every_timer = {0, 0, 0, 0, 0};
#endif
/* the event code */
#ifdef HASEVENTS
/* should go to the headers eventually */
#define EVENTLISTSIZE 4
/* the event list, nevents is the number of active events */
mem_t nevents = 0;
int ievent = 0;
mem_t events_enabled = 1;
volatile bevent_t eventlist[EVENTLISTSIZE];
/* the extension of the GOSUB stack */
mem_t gosubarg[GOSUBDEPTH];
#endif
#ifdef HASERRORHANDLING
/* the error handler type, very simple for now */
typedef struct {
mem_t type;
address_t linenumber;
} berrorh_t;
berrorh_t berrorh = {0 , 0};
mem_t erh = 0;
#endif
/* the string for real time clocks */
char rtcstring[20] = { 0 };
/* the units pulse operates on, in microseconds*/
address_t bpulseunit = 10;
/* only needed if the break condition is handled in the background */
char breakcondition = 0;
/* the FN context, how deep are we in a nested function call, negative values reserved */
int fncontext = 0;
/* the accuracy of a equal or not equal statement on numbers */
#ifdef HASFLOAT
number_t epsilon = 0;
#else
const number_t epsilon = 0;
#endif
/* the number of digits displayed in the fraction of a float */
#ifdef HASFLOAT
mem_t precision = 5;
#endif
/*
* BASIC timer stuff, this is a core interpreter function now
*/
/* the millis function for BASIC */
void bmillis() {
number_t m;
/* millis is processed as integer and is cyclic mod maxnumber and not cast to float!! */
m = (number_t) (millis() / (unsigned long)pop() % (unsigned long)maxnum);
push(m);
}
/*
* Determine the possible basic memory size.
* using malloc causes some overhead which can be relevant on the smaller
* boards.
*
* Set MEMSIZE instead to a static value. In this case ballocmem
* just returns the static MEMSIZE.
*
* If SPIRAMINTERFACE is defined, we use the memory from a serial RAM and dont
* allocate it here at all.
*/
#if (!defined(MEMSIZE) || MEMSIZE == 0) && !(defined(SPIRAMINTERFACE))
address_t ballocmem() {
/* on most platforms we know the free memory for BASIC, this comes from runtime */
long m = freememorysize();
/* we subtract some language feature depended things, this is only needed on
small Arduino boards with memories below 16kb */
if (m < 16000) {
#ifdef HASAPPLE1
m -= 64; /* strings cost memory */
#endif
#ifdef USELONGJUMP
m -= 160; /* odd but true on Ardunio UNO and the like */
#endif
#ifdef HASFLOAT
m -= 96;
#endif
#ifdef HASGRAPH
m -= 256;
#endif
}
/* and keep fingers crossed here */
if (m < 0) m = 128;
/* we allocate as much as address_t can handle */
if (m > maxaddr) m = maxaddr;
/* try to allocate the memory */
mem = (mem_t*)malloc(m);
if (mem != 0) return m - 1;
/* fallback if allocation failed, 128 bytes */
mem = (mem_t*)malloc(128);
if (mem != 0) return 128; else return 0;
}
#else
address_t ballocmem() {
return MEMSIZE - 1;
};
#endif
/*
Layer 0 function - variable handling.
These function access variables and data
*/
/*
Eeprom load / save / autorun functions
needed for SAVE and LOAD to an EEPROM
autorun is generic.
The eeprom is accessed through the runtime functions
elength(), eupdate(), ewrite() and eflush();
*/
/* save a file to EEPROM, disabled if we use the EEPROM directly */
void esave() {
#ifndef EEPROMMEMINTERFACE
address_t a = 0;
/* does the program fit into the eeprom */
if (top + eheadersize < elength()) {
/* EEPROM per default is 255, 0 indicates that there is a program */
eupdate(a++, 0);
/* store the size of the program in byte 1,2,... of the EEPROM*/
setaddress(a, beupdate, top);
a += addrsize;
/* store the program */
while (a < top + eheadersize) {
eupdate(a, memread2(a - eheadersize));
a++;
}
eupdate(a++, 0);
/* needed on I2C EEPROM and other platforms where we buffer */
eflush();
} else {
error(EOUTOFMEMORY);
er = 0;
}
#endif
}
/* load a file from EEPROM, disabled if the use the EEPROM directly */
void eload() {
#ifndef EEPROMMEMINTERFACE
address_t a = 0;
/* have we stored a program? */
if (elength() > 0 && (eread(a) == 0 || eread(a) == 1)) {
/* how long is it? */
a++;
top = getaddress(a, beread);
a += addrsize;
/* load it to memory, memwrite2 is direct mem access */
while (a < top + eheadersize) {
memwrite2(a - eheadersize, beread(a));
a++;
}
} else {
/* no valid program data is stored */
error(EEEPROM);
}
#endif
}
/* autorun something from EEPROM or a filesystem */
char autorun() {
/* autorun from EEPROM if there is an EEPROM flagged for autorun */
if (elength() > 0 && eread(0) == 1) { /* autorun from the EEPROM */
top = getaddress(1, beread);
st = SERUN;
return 1; /* EEPROM autorun overrules filesystem autorun */
}
/* autorun from a given command line argument, if we have one */
#ifdef HASARGS
if (bargc > 1 && ifileopen(bargv[1])) {
xload(bargv[1]);
st = SRUN;
ifileclose();
bnointafterrun = TERMINATEAFTERRUN;
return 1;
}
#endif
/* on a platform with a file system, autoexec from a file */
#if defined(FILESYSTEMDRIVER)
if (ifileopen("autoexec.bas")) {
xload("autoexec.bas");
st = SRUN;
ifileclose();
return 1;
}
#endif
/* nothing to autorun */
return 0;
}
#ifdef HASAPPLE1
/*
The new malloc code. Heap structure is now
payload
(payload size)
name
type
In the new heap implementation himem points to the first free byte on the heap.
The payload is stored first and then the header.
The new heap code uses name_t for the name of the object.
*/
address_t bmalloc(name_t* name, address_t l) {
address_t payloadsize; /* the payload size */
address_t heapheadersize = sizeof(name_t) + addrsize; /* this is only used to estimate the free space, it is the maximum */
address_t b = himem; /* the current position on the heap, we store it in case of errors */
/* Initial DEBUG message. */
if (DEBUG) {
outsc("** bmalloc with token ");
outnumber(name->token); outspc();
outname(name); outspc();
outnumber(l); outcr();
}
/*
How much space does the payload of the object need?
*/
switch (name->token) {
case VARIABLE: /* a variable needs numsize bytes*/
payloadsize = numsize;
break;
#ifndef HASMULTIDIM
case ARRAYVAR: /* a one dimensional array needs numsize*l bytes */
payloadsize = numsize * l;
break;
#else
case ARRAYVAR: /* a two dimensional array needs numsize*l bytes plus one word for the additional dimension*/
payloadsize = numsize * l + addrsize;
break;
#endif
#ifdef HASDARTMOUTH
case TFN: /* the jump address, the type of function/type of return value, the number of vars
and all variables are stored*/
payloadsize = addrsize + 2 + sizeof(name_t) * l;
break;
#endif
/* these are plain buffers allocated by the MALLOC call in BASIC */
default:
payloadsize = l;
}
/* enough memory ?, on an EEPROM system we limit the heap to the RAM */
#ifndef EEPROMMEMINTERFACE
if ((himem - top) < payloadsize + heapheadersize) {
error(EOUTOFMEMORY);
return 0;
}
#else
if (himem - (elength() - eheadersize) < payloadsize + heapheadersize) {
error(EOUTOFMEMORY);
return 0;
}
#endif
/* first we reserve space for the payload, address points to the first byte of the payload */
/* b points to the first free byte after the payload*/
b -= payloadsize;
bfind_object.address = b + 1;
/* for ARRAYS, STRINGS and BUFFERS, store the object length now - these are variable size objects*/
if (name->token != VARIABLE) {
b -= (addrsize - 1);
setaddress(b, memwrite2, payloadsize);
if (DEBUG) {
outsc("** bmalloc writes payloadsize "); outnumber(payloadsize);
outsc(" at "); outnumber(b); outcr();
}
b--;
}
/* store the name of the objects including the type as identifier */
b = setname_heap(b, name);
/* store the type of the object */
memwrite2(b--, name->token);
/* if anything went wrong we exit here without changing himem */
if (b < top || er) {
error(EOUTOFMEMORY);
return 0;
}
/* we fill the cache here as well, both right now for compatibility */
bfind_object.name = *name;
bfind_object.size = payloadsize;
/* himem is the next free byte now again */
himem = b;
if (DEBUG) {
outsc("** bmalloc returns "); outnumber(bfind_object.address);
outsc(" himem is "); outnumber(himem); outcr();
}
/* return the address of the payload */
return bfind_object.address;
}
address_t bfind(name_t* name) {
address_t b, b0;
address_t i = 0;
/* Initial DEBUG message. */
if (DEBUG) {
outsc("*** bfind called for "); outname(name);
outsc(" on heap with token "); outnumber(name->token);
outsc(" himem is "); outnumber(himem); outcr();
}
/* do we have anything on the heap? */
if (himem == memsize) return 0; else b = himem + 1;
/* we have the object already in cache and return */
if (name->token == bfind_object.name.token && cmpname(name, &bfind_object.name)) {
if (DEBUG) {
outsc("*** bfind found in cache ");
outname(name);
outsc(" at ");
outnumber(bfind_object.address);
outcr();
}
return bfind_object.address;
}
/* walk through the heap from the last object added to the first */
while (b <= memsize) {
/* get the name and the type and advance */
bfind_object.name.token = memread2(b++);
b = getname(b, &bfind_object.name, memread2);
/* determine the size of the object and advance */
if (bfind_object.name.token != VARIABLE) {
bfind_object.size = getaddress(b, memread2);
b += addrsize;
} else {
bfind_object.size = numsize;
}
/* this is the location of the payload */
bfind_object.address = b;
/* have we found the object */
if (name->token == bfind_object.name.token && cmpname(name, &bfind_object.name)) {
if (DEBUG) {
outsc("*** bfind found ");
outname(name);
outsc(" at ");
outnumber(bfind_object.address);
outcr();
}
return bfind_object.address;
}
/* advance on the heap */
b0 = b;
b += bfind_object.size;
/* safety net for wraparound situations - should never happen - means corrupt heap */
if (b0 > b) {
error(EVARIABLE);
return 0;
}
}
/* nothing found return 0 and clear the cache */
if (DEBUG) {
outsc("bfind returns 0");
outcr();
}
zeroheap(&bfind_object);
return 0;
}
/* reimplementation bfree with name interface */
address_t bfree(name_t* name) {
address_t b;
address_t i;
if (DEBUG) {
outsc("*** bfree called for ");
outname(name);
outsc(" on heap with token ");
outnumber(name->token);
outcr();
}
/* use bfind to find the place */
b = bfind(name);
/* nothing found, return 0 */
if (b == 0) return 0;
if (DEBUG) {
outsc("** bfree found ");
outnumber(b);
outcr();
}
/* clear the entire memory area */
for (i = himem; i <= b + bfind_object.size - 1; i++) memwrite2(i, 0);
/* set the number of variables to the new value */
himem = b + bfind_object.size - 1;
if (DEBUG) {
outsc("** bfree returns ");
outnumber(himem);
outcr();
}
/* forget the chache, because heap structure has changed !! */
zeroheap(&bfind_object);
return himem;
}
/* the length of an object, we directly return from the cache */
address_t blength(name_t* name) {
if (bfind(name)) return bfind_object.size; else return 0;
}
#endif /* HASAPPLE1 */
/* reimplementation of getvar and setvar with name_t */
number_t getvar(name_t *name) {
address_t a;
if (DEBUG) {
outsc("* getvar ");
outname(name);
outspc();
outcr();
}
/* the special variables */
if (name->c[0] == '@') {
#ifdef HASLONGNAMES
if (name->l == 1) name->c[1] = 0; /* to make sure @ alone works */
#endif
switch (name->c[1]) {
case 'A':
return availch();
case 'S':
return ert | ioer;
case 'I':
return id;
case 'O':
return od;
case 'T':
return millis();
case 'C':
if (availch()) return inch(); else return 0;
case 'E':
return elength() / numsize;
case 0:
return (himem - top) / numsize;
case 'R':
return rd;
#ifdef HASSTEFANSEXT
case 'U':
return getusrvar();
#endif
#ifdef HASFLOAT
case 'P':
return epsilon;
#endif
#ifdef HASIOT
case 'V':
return vlength;
#endif
#if defined(DISPLAYDRIVER) || defined (GRAPHDISPLAYDRIVER)
case 'X':
return dspgetcursorx();
case 'Y':
return dspgetcursory();
#endif
}
}
#ifdef HASAPPLE1
/* search the heap first */
a = bfind(name);
if (!USELONGJUMP && er) return 0;
/* if we don't find on the heap and it is not a static variable, we autocreate */
if (a == 0) {
a = bmalloc(name, 0);
if (!USELONGJUMP && er) return 0;
}
/* something went wrong */
if (a == 0) {
error(EVARIABLE);
return 0;
}
/* retrieve the value */
return getnumber(a, memread2);
#else
/* we only have the static variable array */
if (name->c[0] >= 65 && name->c[0] <= 91 && name->c[1] == 0) return vars[name->c[0] - 65];
/* systems without Apple1 extension i.e. HEAP throw an error */
error(EVARIABLE);
return 0;
#endif
}
/* set and create a variable */
void setvar(name_t *name, number_t v) {
address_t a;
if (DEBUG) {
outsc("* setvar ");
outname(name);
outspc();
outnumber(v);
outcr();
}
/* the special variables */
if (name->c[0] == '@')
switch (name->c[1]) {
case 'S':
ert = v;
ioer = v;
return;
case 'I':
id = v;
return;
case 'O':
od = v;
return;
case 'T':
return;
case 'C':
outch(v);
return;
case 'R':
rd = v;
return;
#ifdef HASTEFANSEXT
case 'U':
setusrvar(v);
return;
#endif
#ifdef HASFLOAT
case 'P':
epsilon = v;
return;
#endif
#ifdef HASIOT
case 'V':
return;
#endif
#if defined(DISPLAYDRIVER) || defined(GRAPHDISPLAYDRIVER)
case 'X':
dspsetcursorx((int)v);
/* set the charcount, this is half broken but works */
#ifdef HASMSTAB
if (od > 0 && od <= OPRT) charcount[od] = v;
#endif
return;
case 'Y':
dspsetcursory((int)v);
return;
#endif
}
#ifdef HASAPPLE1
/* dynamically allocated vars */
a = bfind(name);
/* autocreate if not found */
if (a == 0) {
a = bmalloc(name, 0);
if (!USELONGJUMP && er) return;
}
/* something went wrong */
if (a == 0) {
error(EVARIABLE);
return;
}
/* set the value */
setnumber(a, memwrite2, v);
#else
/* the static variable array */
if (name->c[1] == 0 && name->c[0] >= 65 && name->c[0] <= 91) {
vars[name->c[0] - 65] = v;
return;
}
error(EVARIABLE);
#endif
}
/* clr all variables */
void clrvars() {
/* delete all static variables */
address_t i;
/* clear static variable (only on no heap systems) */
#ifndef HASAPPLE1
for (i = 0; i < VARSIZE; i++) vars[i] = 0;
#endif
/* then set the entire mem area to zero */
for (i = himem; i < memsize; i++) memwrite2(i, 0);
/* reset the heap start*/
himem = memsize;
/* and clear the cache */
#ifdef HASAPPLE1
zeroheap(&bfind_object);
#endif
}
/*
The BASIC memory access function.
getnumber2, getaddress and getstrlength are purely local, they
can be used with any memory reader function unlike the old BASIC 1
code.
*/
/*
To avoid nasty warnings we encapsulate the EEPROM access functions
from runtime.c
This is only needed for the get* and set* functions as we use the
memreader_t and memwriter_t function pointers here.
This way, types in runtime.c can be changed without changing the
BASIC interpreter code.
*/
mem_t beread(address_t a) {
return eread(a);
}
void beupdate(address_t a, mem_t v) {
eupdate(a, v);
}
/* a generic memory reader for numbers */
number_t getnumber(address_t m, memreader_t f) {
mem_t i;
accu_t z;
for (i = 0; i < numsize; i++) z.c[i] = f(m++);
return z.n;
}
/* same for addresses */
address_t getaddress(address_t m, memreader_t f) {
mem_t i;
accu_t z;
for (i = 0; i < addrsize; i++) z.c[i] = f(m++);
return z.a;
}
/* same for strings */
stringlength_t getstrlength(address_t m, memreader_t f) {
mem_t i;
accu_t z;
z.a = 0;
for (i = 0; i < strindexsize; i++) z.c[i] = f(m++);
return z.a;
}
/* set a number at a memory location, new version */
void setnumber(address_t m, memwriter_t f, number_t v) {
mem_t i;
accu_t z;
z.n = v;
for (i = 0; i < numsize; i++) f(m++, z.c[i]);
}
/* set an address at a memory location */
void setaddress(address_t m, memwriter_t f, address_t a) {
mem_t i;
accu_t z;
z.a = a;
for (i = 0; i < addrsize; i++) f(m++, z.c[i]);
}
/* set a stringlength at a memory location */
void setstrlength(address_t m, memwriter_t f, stringlength_t s) {
mem_t i;
accu_t z;
z.s = s;
for (i = 0; i < strindexsize; i++) f(m++, z.c[i]);
}
/*
Code to handle names. These function mostly deal with the true
name part of name_t and not the token. The token has to be
processed by the caller. Name byte order conventon is
to have the first character in the lower byte and the second
character in the higher byte. Optionally, for HASLONGNAMES
the length of the name is stored before the name.
setname_* sets a name and advance the number of bytes the name uses.
Two versions are needed because the heap is counted down
while the pgm is counted up.
getname needs to go through a memreader because names are
read from eeproms as well!
Currently the old code with twobyte names is still in place
if HASLONGNAMES is not defined. Default is now to have long names.
*/
#ifndef HASLONGNAMES
/* this one is for the heap were we count down writing*/
address_t setname_heap(address_t m, name_t* name) {
memwrite2(m--, name->c[1]);
memwrite2(m--, name->c[0]);
return m;
}
/* this one is for the pgm were we count up writing */
address_t setname_pgm(address_t m, name_t* name) {
memwrite2(m++, name->c[0]);
memwrite2(m++, name->c[1]);
return m;
}
/* get a name from a memory location */
address_t getname(address_t m, name_t* name, memreader_t f) {
name->c[0] = f(m++);
name->c[1] = f(m++);
return m;
}
/* compare two names */
mem_t cmpname(name_t* a, name_t* b) {
if (a->c[0] == b->c[0] && a->c[1] == b->c[1]) return 1; else return 0;
}
/* copy the entire name stucture */
void copyname(name_t* a, name_t* b) {
a->c[0] = b->c[0];
a->c[1] = b->c[1];
a->token = b->token;
}
/* zero a name and a heap object */
void zeroname(name_t* name) {
name->c[0] = 0;
name->c[1] = 0;
name->token = 0;
}
void zeroheap(heap_t* heap) {
heap->address = 0;
heap->size = 0;
zeroname(&heap->name);
}
/* output a name */
void outname(name_t* name) {
outch(name->c[0]);
if (name->c[1]) outch(name->c[1]);
}
#else
/* this one is for the heap were we count down writing*/
address_t setname_heap(address_t m, name_t* name) {
mem_t l;
for (l = name->l; l > 0; l--) memwrite2(m--, name->c[l - 1]);
memwrite2(m--, name->l);
return m;
}
/* this one is for the pgm were we count up writing */
address_t setname_pgm(address_t m, name_t* name) {
mem_t l;
memwrite2(m++, name->l);
for (l = 0; l < name->l; l++) memwrite2(m++, name->c[l]);
return m;
}
/* get a name from a memory location */
address_t getname(address_t m, name_t* name, memreader_t f) {
mem_t l;
name->l = f(m++);
for (l = 0; l < name->l; l++) name->c[l] = f(m++);
// for(; l<MAXNAME; l++) name->c[l]=0; /* should not be there, is needed for */
/* not having this here causes the obscure function namehandling bug if xfn does not do a zeroname
have not yet found the root cause for this */
return m;
}
/* compare two names */
mem_t cmpname(name_t* a, name_t* b) {
mem_t l;
if (a->l != b->l) return 0;
for (l = 0; l < a->l; l++) if (a->c[l] != b->c[l]) return 0;
return 1;
}
/* copy the entire name stucture */
void copyname(name_t* a, name_t* b) {
mem_t l;
a->l = b->l;
for (l = 0; l < b->l; l++) a->c[l] = b->c[l];
a->token = b->token;
if (a->l == 1) a->c[1] = 0; /* this is needed for compatibility with the short name code when handling special vars */
}
/* zero a name and a heap object */
void zeroname(name_t* name) {
mem_t l;
name->l = 0;
for (l = 0; l < MAXNAME; l++) name->c[l] = 0;
name->token = 0;
}
void zeroheap(heap_t* heap) {
heap->address = 0;
heap->size = 0;
zeroname(&heap->name);
}
/* output a name */
void outname(name_t* name) {
mem_t l;
for (l = 0; l < name->l; l++) outch(name->c[l]);
}
#endif
/*
Create an array.
Arrays are created on the heap. This code allows redimensioning of arrays
which leads to a new array with the same name on the heap. This new
array is found first in a heap search. This ways we can have arrays
as local variables.
msarraylimits is a flag to indicate that arrays should be created with
0-n elements like in Microsoft BASIC.
*/
address_t createarray(name_t* variable, address_t i, address_t j) {
address_t a;
/* if we want to me MS compatible, the array ranges from 0-n */
if (msarraylimits) {
i += 1;
j += 1;
}
/* this code allows redimension now for local variables */
#ifdef HASAPPLE1
if (DEBUG) {
outsc("* create array "); outname(variable); outspc();
outsc("* with name length "); outnumber(variable->l); outspc();
outnumber(i); outspc(); outnumber(j); outcr();
}
#ifndef HASMULTIDIM
return bmalloc(variable, i);
#else
/* allocate the array space */
a = bmalloc(variable, i * j);
/* store the dimension of the array at the beginning of the array area */
setaddress(a + i * j * numsize, memwrite2, j);
/* return value is the address of the payload area */
return a;
#endif
#endif
return 0;
}
/*
The array function.
We use the lefthandside object here with the convention that i is the first index
and j the second index. This is inconsistent with the use in strings. Will be fixed
when a true indexing type is introduced.
*/
void array(lhsobject_t* object, mem_t getset, number_t* value) {
address_t a; /* the address of the array element */
address_t h; /* the number of elements in the array */
address_t l = arraylimit; /* the lower limit, defaults to the arraylimit, here for further use */
address_t dim = 1; /* the array dimension */
if (DEBUG) {
outsc("* array: accessing ");
outname(&name); outspc(); outspc();
outnumber(object->i); outspc();
outnumber(object->j); outspc();
outsc(" getset "); outch(getset); outcr();
}
/* handling the special array, range check and access is done here */
if (object->name.c[0] == '@') {
switch (object->name.c[1]) {
/* @E ranges from 1 to the end of the EEPROM minus the header */
case 'E':
h = elength() / numsize;
a = elength() - numsize * object->i;
if (a < eheadersize || a > elength() - numsize) {
error(EORANGE);
return;
}
if (getset == 'g') *value = getnumber(a, beread);
else if (getset == 's') setnumber(a, beupdate, *value);
return;
#if defined(DISPLAYDRIVER) && defined(DISPLAYCANSCROLL)
case 'D':
if (getset == 'g') *value = dspget(object->i - 1);
else if (getset == 's') dspset(object->i - 1, *value);
return;
#endif
#if defined(HASCLOCK)
case 'T':
if (getset == 'g') *value = rtcget(object->i);
else if (getset == 's') rtcset(object->i, *value);
return;
#endif
#if defined(ARDUINO) && defined(ARDUINOSENSORS)
case 'S':
if (getset == 'g') *value = sensorread(object->i, 0);
return;
#endif
#ifdef HASSTEFANSEXT
case 'U':
if (getset == 'g') *value = getusrarray(object->i);
else if (getset == 's') setusrarray(object->i, *value);
return;
#endif
case 0:
h = (himem - top) / numsize;
a = himem - numsize * (object->i + 1) + 1;
if (object->i < 0 || a < top) {
error(EORANGE);
return;
}
if (getset == 'g') *value = getnumber(a, memread2);
else if (getset == 's') setnumber(a, memwrite2, *value);
return;
#ifdef HASSTEFANSEXT
case 'M':
h = himem - top;
a = himem - object->i;
if (object->i < 0 || a < top) {
error(EORANGE);
return;
}
if (getset == 'g') *value = memread2(a);
else if (getset == 's') memwrite2(a, *value);
return;
#endif
case 'P':
/* the io ports */
if (object->i >= 0 && object->i < 16) {
if (getset == 'g') *value = portread(object->i);
else if (getset == 's') portwrite(object->i, *value);
return;
}
/* the data direction registers */
if (object->i >= 16 && object->i < 32) {
if (getset == 'g') *value = ddrread(object->i - 16);
else if (getset == 's') ddrwrite(object->i - 16, *value);
return;
}
/* the pin registers (only input) */
if (object->i >= 32 && object->i < 48) {
if (getset == 'g') *value = pinread(object->i - 32);
return;
}
default:
error(EVARIABLE);
return;
}
} else {
/* dynamically allocated arrays */
#ifdef HASAPPLE1
object->name.token = ARRAYVAR;
if (!(a = bfind(&object->name))) a = createarray(&object->name, ARRAYSIZEDEF, 1);
if (!USELONGJUMP && er) return;
/* multidim reserves one address word for the dimension, hence we have less bytes */
#ifndef HASMULTIDIM
h = bfind_object.size / numsize;
#else
h = (bfind_object.size - addrsize) / numsize;
#endif
if (DEBUG) {
outsc("** in array dynamical base address "); outnumber(a);
outsc(" and array element number "); outnumber(h);
outcr();
}
#ifdef HASMULTIDIM
dim = getaddress(a + bfind_object.size - addrsize, memread2);
if (DEBUG) {
outsc("** in array, second dimension is "); outnumber(dim);
outspc(); outnumber(a + bfind_object.size);
outcr();
}
a = a + ((object->i - l) * dim + (object->j - l)) * numsize;
#else
a = a + (object->i - l) * numsize;
#endif
#else /* no array code */
error(EVARIABLE);
return;
#endif
}
/* range check */
#ifdef HASMULTIDIM
if ( (object->j < l) || (object->j >= dim + l) || (object->i < l) || (object->i >= h / dim + l)) {
error(EORANGE);
return;
}
#else
if ( (object->i < l) || (object->i >= h + l) ) {
error(EORANGE);
return;
}
#endif
/* set or get the array */
if (getset == 'g') *value = getnumber(a, memread2);
else if (getset == 's') setnumber(a, memwrite2, *value);
}
/*
Create a string on the heap.
i is the length of the string, j the dimension of the array.
String objects are either plain strings or arrays. In case of arrays
the number of strings is stored at the end of the array.
*/
address_t createstring(name_t* variable, address_t i, address_t j) {
#ifdef HASAPPLE1
address_t a;
if (DEBUG) {
outsc("Create string ");
outname(variable);
outcr();
}
/* correct create length if arraylimit is not 1 */
j = (j - arraylimit) + 1;
/* the MS string compatibility, DIM 10 creates 11 elements */
if (msarraylimits) j += 1;
#ifndef HASMULTIDIM
/* if no string arrays are in the code, we reserve the number of bytes i and space for the index */
/* allow redimension without check right now, for local variables */
a = bmalloc(variable, i + strindexsize);
if (er != 0) return 0;
return a;
#else
/* string arrays need the number of array elements which address_ hence addresize bytes and then
the space for j strings */
/* allow redimension without check right now, for local variables */
a = bmalloc(variable, addrsize + j * (i + strindexsize));
if (er != 0) return 0;
/* set the array length */
setaddress(a + j * (i + strindexsize), memwrite2, j);
/* return the address of the first string */
return a;
#endif
if (er != 0) return 0;
return a;
#else
return 0;
#endif
}
/*
Get a string at position b.
getstring returns a pointer to the first string element in question.
There is a lo tof complexity in the code to support systems with serial
memory.
*/
#ifdef HASAPPLE1
/* helpers to handle strings */
/* Stores a C string to a BASIC string variable */
void storecstring(address_t ax, address_t s, char* b) {
address_t k;
for (k = 0; k < s - strindexsize && b[k] != 0; k++) memwrite2(ax + k + strindexsize, b[k]);
setstrlength(ax, memwrite2, k);
}
/* length of a c string up to a limit l */
address_t cstringlength(char* c, address_t l) {
address_t a;
while (a < l && c[a] != 0) a++;
return a;
}
/* get a memory pointer to a string, new version */
void getstring(string_t* strp, name_t* name, address_t b, address_t j) {
address_t k, zt;
address_t ax;
/* we know nothing about the string */
ax = 0;
strp->address = 0;
strp->ir = 0;
strp->length = 0;
strp->arraydim = 1;
strp->strdim = 0;
if (DEBUG) {
outsc("* getstring from var "); outname(name); outspc();
outnumber(b); outspc();
outnumber(j); outcr();
}
/* special string variables */
if (name->c[0] == '@')
switch (name->c[1]) {
case 0:
strp->ir = ibuffer + b;
strp->length = ibuffer[0];
strp->strdim = BUFSIZ - 2;
return;
default:
error(EVARIABLE);
return;
case 'U':
makeusrstring(); /* a user definable special string in sbuffer */
strp->ir = sbuffer + b;
strp->length = sbuffer[0];
return;
#ifdef HASCLOCK
case 'T':
rtcmkstr(); /* the time string */
strp->ir = rtcstring + b;
strp->length = rtcstring[0];
return;
#endif
/* the arguments string on POSIX systems */
#ifdef HASARGS
case 'A':
if (bargc > 2) {
strp->ir = bargv[2];
strp->length = cstringlength(bargv[2], BUFSIZE);
return;
}
return;
#endif
}
/* dynamically allocated strings, create on the fly */
if (!(ax = bfind(name))) ax = createstring(name, defaultstrdim, arraylimit);
if (DEBUG) {
outsc("** heap address "); outnumber(ax); outcr();
if (ax) {
outsc("** byte length of string memory segment ");
outnumber(bfind_object.size);
outcr();
}
}
/* string creating has caused an error, typically no memoryy */
if (!USELONGJUMP && er) return;
#ifndef HASMULTIDIM
/* the maximum length of the string */
strp->strdim = bfind_object.size - strindexsize;
/* are we in range */
if ((b < 1) || (b > strp->strdim )) {
error(EORANGE);
return;
}
if (DEBUG) {
outsc("** maximum string length ");
outnumber(strp->strdim);
outcr();
}
/* get the actual full length, this is redundant to lenstring but lenstring does
not autocreate */
strp->length = getstrlength(ax, memread2);
/* now find the payload address */
ax = ax + strindexsize + (b - 1);
#else
/* the dimension of the string array */
/* it is at the top of the string, this uses a side effect of bfind */
strp->arraydim = getaddress(ax + bfind_object.size - addrsize, memread2);
/* is the array index in range */
if ((j < arraylimit) || (j >= strp->arraydim + arraylimit )) {
error(EORANGE);
return;
}
if (DEBUG) {
outsc("** string dimension ");
outnumber(strp->arraydim);
outcr();
}
/* the max length of a string */
strp->strdim = (bfind_object.size - addrsize) / strp->arraydim - strindexsize;
/* are we in range */
if ((b < 1) || (b > strp->strdim )) {
error(EORANGE);
return;
}
if (DEBUG) {
outsc("** maximum string length ");
outnumber(strp->strdim);
outcr();
}
/* the base address of a string */
ax = ax + (j - arraylimit) * (strp->strdim + strindexsize);
if (DEBUG) {
outsc("** string base address ");
outnumber(ax);
outcr();
}
/* from this base address we can get the actual length of the string */
strp->length = getstrlength(ax, memread2);
/* the address of the payload */
ax = ax + b - 1 + strindexsize;
#endif
if (DEBUG) {
outsc("** payload address ");
outnumber(ax);
outcr();
}
/* store the payload address to the string object, length to be done if needed!! */
strp->address = ax;
/* return value is 0 if we have no direct memory access, the caller needs to handle the string
through the mem address */
#ifdef USEMEMINTERFACE
strp->ir = 0;
#else
strp->ir = (char *)&mem[ax];
#endif
}
/* reimplementation with name_t */
/* set the length of a string */
void setstringlength(name_t* name, address_t l, address_t j) {
address_t a;
stringlength_t stringdim;
if (DEBUG) {
outsc("** setstringlength ");
outname(name);
outspc(); outnumber(l); outspc(); outnumber(j);
outcr();
}
/* the special strings */
if (name->c[0] == '@')
switch (name->c[1]) {
case 0:
*ibuffer = l;
return;
case 'U':
/* do nothing here for the moment */
return;
}
/* find the variable address */
a = bfind(name);
if (!USELONGJUMP && er) return;
if (a == 0) {
error(EVARIABLE);
return;
}
/* stringdim calculation moved here */
#ifndef HASMULTIDIM
stringdim = bfind_object.size - strindexsize;
#else
/* getaddress seeks the dimension of the string array directly after the payload */
stringdim = (bfind_object.size - addrsize) / (getaddress(a + bfind_object.size - addrsize, memread2)) - strindexsize;
#endif
/* where do we write it to */
a = a + (stringdim + strindexsize) * (j - arraylimit);
if (DEBUG) {
outsc("** setstringlength writing to ");
outnumber(a);
outsc(" value ");
outnumber(l);
outcr();
}
setstrlength(a, memwrite2, l);
}
/* the BASIC string mechanism for real time clocks, create a string with the clock data */
#ifdef HASCLOCK
void rtcmkstr() {
int cc = 1;
int t;
/* hours */
t = rtcget(2);
rtcstring[cc++] = t / 10 + '0';
rtcstring[cc++] = t % 10 + '0';
rtcstring[cc++] = ':';
/* minutes */
t = rtcget(1);
rtcstring[cc++] = t / 10 + '0';
rtcstring[cc++] = t % 10 + '0';
rtcstring[cc++] = ':';
/* seconds */
t = rtcget(0);
rtcstring[cc++] = t / 10 + '0';
rtcstring[cc++] = t % 10 + '0';
rtcstring[cc++] = '-';
/* days */
t = rtcget(4);
if (t / 10 > 0) rtcstring[cc++] = t / 10 + '0';
rtcstring[cc++] = t % 10 + '0';
rtcstring[cc++] = '/';
/* months */
t = rtcget(5);
if (t / 10 > 0) rtcstring[cc++] = t / 10 + '0';
rtcstring[cc++] = t % 10 + '0';
rtcstring[cc++] = '/';
/* years */
t = rtcget(6) % 100; /* only 100 years no 19xx epochs */
if (t / 10 > 0) rtcstring[cc++] = t / 10 + '0';
rtcstring[cc++] = t % 10 + '0';
rtcstring[cc] = 0;
/* needed for BASIC strings */
rtcstring[0] = cc - 1;
}
#endif
#endif
/*
Layer 0 Extension: the user defined extension functions, use this function for a
quick way to extend BASIC.
@U is a single variable that can be set and get. Every access to this variable
calls getusrvar() or setusrvar().
@U() is a 1d array every access calls get or setusrarray().
@U$ is a read only string created by makeusrstring().
USR(32, V) is a user defined function created by usrfunction().
CALL 32 is a user defined call
*/
/* read or write the variable @U, you can do anything you want here */
number_t getusrvar() {
return 0;
}
void setusrvar(number_t v) {
return;
}
/* read or write the array @U(), you can do anything you want here */
number_t getusrarray(address_t i) {
return 0;
}
void setusrarray(address_t i, number_t v) {
return;
}
/* make the usr string from @U$, this function can be called multiple times for one operation */
void makeusrstring() {
/*
sample code could be:
mem_t i;
const char text[] = "hello world";
for(i=0; i<SBUFSIZE-1 && text[i]!=0 ; i++) sbuffer[i]=text[i];
Always set sbuffer[0] to the string length, keep in mind that sbuffer
is 32 bytes long by default
*/
sbuffer[0] = 0;
}
/* USR with arguments > 31 calls this */
number_t usrfunction(address_t i, number_t v) {
return 0;
}
/* CALL with arguments > 31 calls this */
void usrcall(address_t i) {
return;
}
/*
Layer 0 - keyword handling - PROGMEM logic goes here
getkeyword(), getmessage(), and getokenvalue() are
the only access to the keyword array in the code.
Same for messages and errors.
All keywords are stored in PROGMEM, the Arduino way to store
constant data in flash memory. sbuffer is used to recall the
keywords and messages from PROGMEM on Arduino. Other systems
use the keyword array directly.
*/
char* getkeyword(address_t i) {
if (DEBUG) {
outsc("** getkeyword from index ");
outnumber(i);
outcr();
}
#ifndef ARDUINOPROGMEM
return (char *) keyword[i];
#else
strcpy_P(sbuffer, (char*) pgm_read_ptr(&(keyword[i])));
return sbuffer;
#endif
}
/* messages are read from the message array */
char* getmessage(char i) {
if (i >= sizeof(message) || i < 0) return 0;
#ifndef ARDUINOPROGMEM
return (char *) message[i];
#else
strcpy_P(sbuffer, (char*) pgm_read_ptr(&(message[i])));
return sbuffer;
#endif
}
/* tokens read here are token_t constructed from multi byte sequences */
token_t gettokenvalue(address_t i) {
if (i >= sizeof(tokens)) return 0;
#ifndef ARDUINOPROGMEM
return tokens[i];
#else
#ifndef HASLONGTOKENS
return (token_t) pgm_read_byte(&tokens[i]);
#else
return (token_t) pgm_read_word(&tokens[i]);
#endif
#endif
}
/* print a message directly to the default outpur stream */
void printmessage(char i) {
#ifndef HASERRORMSG
if (i > EGENERAL) return;
#endif
outsc((char *)getmessage(i));
}
/*
Layer 0 - error handling
The general error handler. The static variable er
contains the error state.
debugtoken() writes a token for debug
bdebug() is the general debug message function
Strategy: the error() function writes the message and then
clears the stack. All calling functions must check er and
return after funtion calls with no further messages etc.
reseterror() sets the error state to normal and end the
run loop.
*/
void error(token_t e) {
address_t i;
/* store the error number */
er = e;
/* clear the stacks */
clearst();
clrforstack();
clrgosubstack();
/* switch off all timers and interrupts */
#ifdef HASTIMER
resettimer(&after_timer);
resettimer(&every_timer);
#endif
/* is the error handler active? then silently go if we do GOTO or CONT actions in it */
#ifdef HASERRORHANDLING
#if !USELONGJUMP
if (st != SINT && (berrorh.type == TGOTO || berrorh.type == TCONT)) return;
#else
if (st != SINT && (berrorh.type == TGOTO || berrorh.type == TCONT)) longjmp(sthook, er);
#endif
#endif
/* set input and output device back to default, and delete the form */
iodefaults();
form = 0;
/* find the line number if in RUN modes */
if (st != SINT) {
outnumber(myline(here));
outch(':');
outspc();
}
/* if we have error messages, display them */
#ifdef HASERRORMSG
if (e > 0)
printmessage(e);
else {
for (i = 0; gettokenvalue(i) != 0 && gettokenvalue(i) != e; i++);
outsc(getkeyword(i));
}
outspc();
printmessage(EGENERAL);
#else
printmessage(EGENERAL);
outspc();
outnumber(er);
#endif
if (DEBUG) {
outsc("** at ");
outnumber(here);
}
outcr();
/* reset fncontext - this is odd */
fncontext = 0;
/* we return to the statement loop, bringing the error with us */
#if USELONGJUMP == 1
longjmp(sthook, er);
#endif
}
void reseterror() {
er = 0;
here = 0;
st = SINT;
}
void debugtoken() {
outsc("* ");
if (debuglevel > 2) {
outnumber(here);
outsc(" * ");
}
if (token == EOL) {
outsc("EOL");
return;
}
switch (token) {
case LINENUMBER:
printmessage(MLINE);
break;
case NUMBER:
printmessage(MNUMBER);
break;
case VARIABLE:
printmessage(MVARIABLE);
break;
case ARRAYVAR:
printmessage(MARRAY);
break;
case STRING:
printmessage(MSTRING);
break;
case STRINGVAR:
printmessage(MSTRINGVAR);
break;
}
outspc();
outputtoken();
}
void bdebug(const char *c) {
outch('*');
outspc();
outsc(c);
debugtoken();
outcr();
}
/*
Arithmetic and runtime operations are mostly done
on a stack of number_t.
push(), pop(), clearst() handle the stack
*/
void push(number_t t) {
if (DEBUG) {
outsc("** push sp= "); outnumber(sp); outcr();
outsc("** push value= "); outnumber(t); outcr();
}
/* in forced integer mode every operation is truncated */
#ifdef HASFLOAT
if (forceint) t = trunc(t);
#endif
if (sp == STACKSIZE)
error(ESTACK);
else
stack[sp++].n = t;
}
number_t pop() {
if (DEBUG) {
outsc("** pop sp= "); outnumber(sp); outcr();
outsc("** pop value= "); outnumber(stack[sp - 1].n); outcr();
}
if (sp == 0) {
error(ESTACK);
return 0;
}
return stack[--sp].n;
}
void pushaddress2(address_t a) {
if (DEBUG) {
outsc("** push sp= "); outnumber(sp); outcr();
outsc("** push value= "); outnumber(a); outcr();
}
if (sp == STACKSIZE)
error(ESTACK);
else
stack[sp++].a = a;
}
address_t popaddress2() {
if (DEBUG) {
outsc("** pop sp= "); outnumber(sp); outcr();
outsc("** pop value= "); outnumber(stack[sp - 1].a); outcr();
}
if (sp == 0) {
error(ESTACK);
return 0;
}
return stack[--sp].a;
}
void pushinteger(index_t i) {
if (DEBUG) {
outsc("** push sp= "); outnumber(sp); outcr();
outsc("** push value= "); outnumber(i); outcr();
}
if (sp == STACKSIZE)
error(ESTACK);
else
stack[sp++].i = i;
}
index_t popinteger() {
if (DEBUG) {
outsc("** pop sp= "); outnumber(sp); outcr();
outsc("** pop value= "); outnumber(stack[sp - 1].i); outcr();
}
if (sp == 0) {
error(ESTACK);
return 0;
}
return stack[--sp].i;
}
/* this one gets a positive integer from the stack and traps the error*/
address_t popaddress() {
number_t tmp = 0;
tmp = pop();
if (tmp < 0) {
error(EORANGE);
return 0;
}
return (address_t) tmp;
}
void clearst() {
sp = 0;
}
/* these are not really stack operations but a way to handle temp char data (not needed right now) */
address_t charsp;
void pushchar(char ch) {}
char popchar() {
return 0;
}
/*
clear the cursor for the READ/DATA mechanism
*/
void clrdata() {
#ifdef HASDARTMOUTH
data = 0;
#endif
}
/*
Stack handling for FOR
Reimplementation of the for stack with names and with all loops
cleaned up.
*/
/* the new stack type for loops */
void pushloop(name_t* name, token_t t, address_t here, number_t to, number_t step) {
address_t i;
if (DEBUG) {
outsc("** loopsp and here in pushloopstack ");
outnumber(loopsp); outspc(); outnumber(here); outcr();
if (name != 0) {
outsc("** loop name ");
outname(name);
outcr();
}
else {
outsc("** loop name is 0");
outcr();
}
outsc("** loop token "); outnumber(t); outcr();
outsc("** loop to "); outnumber(to); outcr();
outsc("** loop step "); outnumber(step); outcr();
}
/*
Before pushing into the loop stack we check is an
old loop exists.
There are two situations to handle:
1. A loop is reentered because a GOTO went back to or even before
the loop start. This is identified by the here location.
2. A new FOR loop is created after the existing loop with the same
variable name. This happens if a jump or break went outside the
loop. This is identified by the variable name.
*/
/* Situation 1, scan for here */
for (i = 0; i < loopsp; i++) {
if (loopstack[i].here == here) {
loopsp = i;
break;
}
}
/* Situation 2, scan for the name */
if (name != 0) {
for (i = 0; i < loopsp; i++) {
if (cmpname(&loopstack[i].var, name)) {
loopsp = i;
break;
}
}
}
/* Add the loop to the stack */
if (loopsp < FORDEPTH) {
if (t == TWHILE || t == TREPEAT) {
loopstack[loopsp].var.token = t;
} else {
if (name != 0) {
loopstack[loopsp].var = *name;
#if defined(HASAPPLE1) && defined(HASLOOPOPT)
loopstack[loopsp].varaddress = bfind(name);
#else
loopstack[loopsp].varaddress = 0;
#endif
} else {
loopstack[loopsp].var.c[0] = 0;
loopstack[loopsp].var.l = 0;
loopstack[loopsp].var.token = 0;
loopstack[loopsp].varaddress = 0;
}
}
loopstack[loopsp].here = here;
loopstack[loopsp].to = to;
loopstack[loopsp].step = step;
loopsp++;
return;
} else
error(ELOOP);
}
/* what is the active loop */
bloop_t* activeloop() {
if (loopsp > 0) {
return &loopstack[loopsp - 1];
} else {
error(ELOOP);
return 0;
}
}
void droploop() {
if (loopsp > 0) {
loopsp--;
} else {
error(ELOOP);
return;
}
}
void clrforstack() {
loopsp = 0;
}
/* GOSUB stack handling */
void pushgosubstack(mem_t a) {
if (gosubsp < GOSUBDEPTH) {
gosubstack[gosubsp] = here;
#ifdef HASEVENTS
gosubarg[gosubsp] = a;
#endif
gosubsp++;
} else
error(TGOSUB);
}
void popgosubstack() {
if (gosubsp > 0) {
gosubsp--;
} else {
error(TRETURN);
return;
}
here = gosubstack[gosubsp];
}
void dropgosubstack() {
if (gosubsp > 0) {
gosubsp--;
} else {
error(TGOSUB);
}
}
void clrgosubstack() {
gosubsp = 0;
}
/* two helper commands for structured BASIC, without the GOSUB stack */
void pushlocation(blocation_t* l) {
if (st == SINT) l->location = bi - ibuffer;
else l->location = here;
l->token = token;
}
void poplocation(blocation_t* l) {
if (st == SINT) bi = ibuffer + l->location;
else here = l->location;
token = l->token;
}
/* little helpers of the io functions */
/* send a newline */
void outcr() {
#ifdef HASSERIAL1
if (sendcr) outch('\r');
#endif
outch('\n');
}
/* send a space */
void outspc() {
outch(' ');
}
/* output a zero terminated string - c style */
void outsc(const char *c) {
while (*c != 0) outch(*c++);
}
/* output a zero terminated string in a formated box padding spaces
needed for catalog output */
void outscf(const char *c, index_t f) {
int i = 0;
while (*c != 0) {
outch(*c++);
i++;
}
if (f > i) {
f = f - i;
while (f--) outspc();
}
}
/*
two console logger functions, they are not needed in BASIC but in the runtime
environment, RTDEBUGSTREAM is the channel to log to
*/
#ifdef RTDEBUG
void consolelog(char* ch) {
mem_t ood = od;
od = RTDEBUGSTREAM;
outsc(ch);
od = ood;
}
void consolelognum(int i) {
mem_t ood = od;
od = RTDEBUGSTREAM;
outnumber(i);
od = ood;
}
#else
void consolelog(char* ch) {}
void consolelognum(int i) {}
#endif
/*
Reading a positive number from a char buffer
maximum number of digits is adjusted to SBUFSIZE
as a fail safe.
This is only for integers.
*/
address_t parsenumber(char *c, number_t *r) {
address_t nd = 0;
*r = 0;
while (*c >= '0' && *c <= '9' && *c != 0) {
*r = *r * 10 + *c++ -'0';
nd++;
if (nd == SBUFSIZE) break;
}
return nd;
}
/*
Reimplementation of parsenumber with the capability
to scan hex, octal, and binary numbers as well.
This is only for integers.
*/
address_t parsenumbern(char *c, number_t *r) {
address_t nd = 0;
mem_t base = 10;
*r = 0;
/* the base */
if (*c == '0') {
c++;
nd++;
if (*c == 'x' || *c == 'X') {
c++;
nd++;
base = 16;
} else if (*c == 'b' || *c == 'B') {
c++;
nd++;
base = 2;
} else if (*c == 'o' || *c == 'O') {
c++;
nd++;
base = 8;
}
}
/* the digits */
while (*c != 0) {
if (base == 16) {
if (*c >= '0' && *c <= '9') *r = *r * 16 + *c - '0';
else if (*c >= 'A' && *c <= 'F') *r = *r * 16 + *c - 'A' + 10;
else if (*c >= 'a' && *c <= 'f') *r = *r * 16 + *c - 'a' + 10;
else break;
} else if (base == 8) {
if (*c >= '0' && *c <= '7') *r = *r * 8 + *c - '0';
else break;
} else if (base == 2) {
if (*c == '0' || *c == '1') *r = *r * 2 + *c - '0';
else break;
} else {
if (*c >= '0' && *c <= '9') *r = *r * 10 + *c - '0';
else break;
}
c++;
nd++;
if (nd == SBUFSIZE) break;
}
return nd;
}
#ifdef HASFLOAT
/* a poor man's atof implementation with character count */
address_t parsenumber2(char *c, number_t *r) {
address_t nd = 0;
index_t i;
number_t fraction = 0;
number_t exponent = 0;
mem_t nexp = 0;
*r = 0;
/* integer part */
i = parsenumber(c, r);
c += i;
nd += i;
/* the fractional part */
if (*c == '.') {
c++;
nd++;
i = parsenumber(c, &fraction);
c += i;
nd += i;
if (i > 0) {
while ((--i) >= 0) fraction = fraction / 10;
*r += fraction;
}
}
/* the exponent */
if (*c == 'E' || *c == 'e') {
c++;
nd++;
if (*c == '-') {
c++;
nd++;
nexp = 1;
};
i = parsenumber(c, &exponent);
nd += i;
while ((--exponent) >= 0) if (nexp) *r = *r / 10; else *r = *r * 10;
}
return nd;
}
#endif
/*
Convert a number to a string.
All writenumber funcions assume that the buffer is large enough.
The caller has to handle this. This normally no problem because
the decimal numbers converted are limited to the size of the
number_t type. For this reason the stringbuffer length in basic.h
is set to 16 time the size of the number_t type.
The argument type controls the largest displayable integer.
wnumber_t is defined in basic.h as either int or long for float
systems.
*/
address_t writenumber(char *c, wnumber_t v) {
address_t nd = 0;
index_t i, j;
mem_t s = 1;
char c1;
/* the sign */
if (v < 0) s = -1;
/* the digits */
do {
c[nd++] = (v % 10) * s + '0';
v = v / 10;
} while (v != 0);
/* print the minus */
if (s < 0 ) c[nd] = '-'; else nd--;
/* reverse the order of digits */
i = 0;
j = nd;
while (j > i) {
c1 = c[i];
c[i] = c[j];
c[j] = c1;
i++;
j--;
}
nd++;
c[nd] = 0;
return nd;
}
/* writenumber with arbitrary base support */
address_t writenumbern(char *c, wnumber_t v, mem_t n) {
address_t nd = 0;
index_t i, j;
mem_t s = 1;
char c1;
/* the sign */
if (v < 0) s = -1;
/* the digits */
do {
c[nd] = (v % n) * s + '0';
v = v / n;
/* for base 16 we need more work */
if (c[nd] > '9') c[nd] = c[nd] + 7;
nd++;
} while (v != 0);
/* print the minus */
if (s < 0 ) c[nd] = '-'; else nd--;
/* reverse the order of digits */
i = 0;
j = nd;
while (j > i) {
c1 = c[i];
c[i] = c[j];
c[j] = c1;
i++;
j--;
}
nd++;
c[nd] = 0;
return nd;
}
#ifdef HASFLOAT
/*
this is for floats, handling output without library
functions as well.
*/
address_t tinydtostrf(number_t v, index_t p, char* c) {
index_t i;
address_t nd = 0;
number_t f;
/* if we are in forced integer mode */
if (forceint) {
v = trunc(v);
return writenumber(c, (int)v);
}
/* we do the sign here */
if (v < 0) {
v = fabs(v);
c[nd++] = '-';
}
/* write the integer part */
nd += writenumber(c + nd, (int)v);
c[nd++] = '.';
/* only the fraction to precision p */
f = fabs(v);
/* get p digits of the fraction */
for (i = p; i > 0; i--) {
f = f - floor(f);
f = f * 10;
c[nd++] = (int)floor(f) + '0';
}
/* and a terminating 0 */
c[nd] = 0;
return nd;
}
address_t writenumber2(char *c, number_t vi) {
index_t i;
index_t nd;
number_t f;
index_t exponent = 0;
mem_t eflag = 0;
const int p = 5;
/* pseudo integers are displayed as integer
zero trapped here */
f = floor(vi);
if (f == vi && fabs(vi) < maxnum) return writenumber(c, vi);
/* earlier, floats where displayed in POSIx using the libraties
return sprintf(c, "%g", vi);
we dont do this any more
*/
/* we check if we have anything to write */
if (!isfinite(vi)) {
c[0] = '*';
c[1] = 0;
return 1;
}
/* normalize the number and see which exponent we have to deal with */
f = vi;
while (fabs(f) < 1.0) {
f = f * 10;
exponent--;
}
while (fabs(f) >= 10.0 - 0.00001) {
f = f / 10;
exponent++;
}
/* there are platforms where dtostrf is broken, we do things by hand in a simple way */
if (exponent > -2 && exponent < 7) {
tinydtostrf(vi, precision, c);
} else {
tinydtostrf(f, precision, c);
eflag = 1;
}
/* remove trailing zeros */
for (i = 0; (i < SBUFSIZE && c[i] != 0 ); i++);
i--;
/* */
while (c[i] == '0' && i > 1) {
i--;
}
i++;
/* add the exponent */
if (eflag && exponent != 0) {
c[i++] = 'E';
i += writenumber(c + i, exponent);
}
c[i] = 0;
return i;
}
#endif
/*
innumber is used as a helper only by xinput(). It reads a number from an input
buffer and returns it in the number_t r. It returns 0 if the number is invalid, 1 if
the number is valid, and -1 if the user has pressed the BREAKCHAR key.
Unlike the old innumber() implementation it is meant to read comma separated numbers
through input. Handling of the buffer is done by the calling function.
The TINYBASICINPUT is an alternative implementation following the Palo Alto BASIC
way of doing it. The expression parser is reused. This allows variables names and
expressions to be used as input as well.
Due to the reuse of sbuffer in the calling function, this will probably only work
in RUN mode.
*/
int innumber(number_t *r, char* buffer, address_t k) {
address_t i = k;
mem_t s = 1;
#ifndef HASTINYBASICINPUT
/* result is zero*/
*r = 0;
/* remove all leading whitespaces first */
while ((buffer[i] == ' ' || buffer[i] == '\t') && i <= (address_t) buffer[0]) i++;
/* is there anything left */
if (i > (address_t) buffer[0]) return 0;
/* now the sign */
if (buffer[i] == '-') {
s = -1;
i++;
}
/* check for the break character */
#if defined(BREAKCHAR)
if (buffer[i] == BREAKCHAR) return -1;
#endif
/* the number */
#ifndef HASFLOAT
if (buffer[i] < '0' || buffer[i] > '9') return 0;
i += parsenumber(&buffer[i], r);
#else
if ((buffer[i] < '0' || buffer[i] > '9') && buffer[i] != '.') return 0;
i += parsenumber2(&buffer[i], r);
#endif
/* the sign */
*r *= s;
return i;
#else
char *b;
token_t t;
/* result is zero */
*r = 0;
/* save the interpreter state */
b = bi;
s = st;
t = token;
/* switch to fake interactive with the buffer as input */
st = SINT;
bi = buffer + k;
/* BREAK handling */
#if defined(BREAKCHAR)
if (*bi == BREAKCHAR) {
return -1;
}
#endif
/* start to interpret the buffer as an expression */
nexttoken();
expression();
/* restore the interpreter state */
i = bi - buffer - 1;
bi = b;
st = s;
token = t;
/* error handling, we trap the error and return zero */
if (er) {
er = 0;
return 0;
}
/* the result is on the stack */
*r = pop();
return i;
#endif
}
/* prints a number */
void outnumber(number_t n) {
address_t nd, i;
/* number write to sbuffer, remember the number of digits in nd */
#ifndef HASFLOAT
nd = writenumber(sbuffer, n);
#else
nd = writenumber2(sbuffer, n);
#endif
/* negative number format aligns right */
if (form < 0) {
i = nd;
while (i < -form) {
outspc();
i++;
}
}
/* the number */
outs(sbuffer, nd);
/* number formats in Palo Alto style, positive numbers align left */
if (form > 0) {
while (nd < form) {
outspc();
nd++;
}
}
}
/*
Layer 1 functions - providing data into the global variable and
changing the interpreter state
*/
/*
Lexical analyser - tokenizes the input line.
nexttoken() increments the input buffer index bi and delivers values in the global
variable token, with arguments in the accumulators ax, x and the index register ir
name is used in the routine.
name, sr, ax and x change values in nexttoken and deliver the result to the calling
function.
bi and ibuffer should not be changed or used for any other function in
interactive node as they contain the state of nexttoken(). In run mode
bi and ibuffer are not used as the program is fully tokenized in mem.
all this is pretty much stateless.
*/
/* skip whitespaces */
void whitespaces() {
while (*bi == ' ' || *bi == '\t') bi++;
}
/* upper case, don't trust the buildins on microcontrollers */
char btoupper(char c) {
if (c >= 'a' && c <= 'z') return c - 32; else return c;
}
/* the token stream */
void nexttoken() {
address_t k, l, i;
char* ir;
char quotechar;
/* RUN mode vs. INT mode, in RUN mode we read from mem via gettoken() */
if (st == SRUN || st == SERUN) {
/* in the token stream we call fastticker - all fast timing functions are in stream */
fastticker();
/* read the token from memory */
gettoken();
/* show what we are doing */
if (debuglevel > 1) {
debugtoken();
outcr();
}
return;
}
/* after change in buffer logic the first byte is reserved for the length */
if (bi == ibuffer) bi++;
/* literal mode only(!) EOL ends literal mode, used to have REM without quotes */
if (lexliteral) {
token = *bi;
if (*bi != '\0') bi++; else lexliteral = 0;
return;
}
/* remove whitespaces outside strings */
whitespaces();
/* end of line token */
if (*bi == '\0') {
token = EOL;
if (DEBUG) debugtoken();
return;
}
/* unsigned numbers, value returned in x */
#ifndef HASFLOAT
if (*bi <= '9' && *bi >= '0') {
bi += parsenumber(bi, &x);
#else
if ((*bi <= '9' && *bi >= '0') || *bi == '.') {
bi += parsenumber2(bi, &x);
#endif
token = NUMBER;
if (DEBUG) debugtoken();
return;
}
/* strings between " " or " EOL, value returned in ir and in sr for now */
if (*bi == '"' || *bi == '\'') {
quotechar = *bi;
k = 0;
bi++;
ir = bi;
sr.ir = bi;
while (*bi != quotechar && *bi != '\0') {
k++;
bi++;
}
bi++;
token = STRING;
sr.length = k;
sr.address = 0; /* we don't find the string in BASIC memory, as we lex from bi */
if (DEBUG) debugtoken();
return;
}
/*
relations
single character relations are their own token
>=, =<, =<, =>, <> are tokenized
*/
if (*bi == '=') {
bi++;
whitespaces();
if (*bi == '>') {
token = GREATEREQUAL;
bi++;
} else if (*bi == '<') {
token = LESSEREQUAL;
bi++;
} else {
token = '=';
}
if (DEBUG) debugtoken();
return;
}
if (*bi == '>') {
bi++;
whitespaces();
if (*bi == '=') {
token = GREATEREQUAL;
bi++;
} else if (*bi == '>') {
token = TSHR;
bi++;
} else {
token = '>';
}
if (DEBUG) debugtoken();
return;
}
if (*bi == '<') {
bi++;
whitespaces();
if (*bi == '=') {
token = LESSEREQUAL;
bi++;
} else if (*bi == '>') {
token = NOTEQUAL;
bi++;
} else if (*bi == '<') {
token = TSHL;
bi++;
} else {
token = '<';
}
if (DEBUG) debugtoken();
return;
}
/*
Keyworks and variables
Isolate a word, bi points to the beginning, l is the length of the word.
ir points to the end of the word after isolating.
@ is a letter here to make the special @ arrays possible.
*/
l = 0;
ir = bi;
while (-1) {
if (*ir >= 'a' && *ir <= 'z') {
if (!lowercasenames) *ir -= 32; /* toupper code, changing the input buffer directly */
ir++;
l++;
} else if ((*ir >= '@' && *ir <= 'Z') || *ir == '_') {
ir++;
l++;
} else {
break;
}
}
/*
Ir is reused here to implement string compares
scanning the keyword array.
Once a keyword is detected the input buffer is advanced
by its length, and the token value is returned.
Keywords are an array of null terminated strings.
They are always matched uppercase.
*/
k = 0;
while (gettokenvalue(k) != 0) {
ir = getkeyword(k);
i = 0;
while (*(ir + i) != 0) {
if (*(ir + i) != btoupper(*(bi + i))) {
k++;
i = 0;
break;
} else
i++;
}
if (i == 0) continue;
bi += i;
token = gettokenvalue(k);
if (token == TREM) lexliteral = 1;
if (DEBUG) debugtoken();
return;
}
/*
A variable has length 2 with either two letters or a letter
and a number. @ can be the first letter of a variable.
Here, no tokens can appear any more as they have been processed
further up.
The longname code supports MAXNAME characters and _ as additional character.
*/
#ifdef HASLONGNAMES
if (l > 0 && l <= MAXNAME) {
token = VARIABLE;
zeroname(&name);
while (((*bi >= '0' && *bi <= '9') ||
(*bi >= '@' && *bi <= 'Z') ||
(*bi >= 'a' && *bi <= 'z') ||
(*bi == '_') ) && name.l < MAXNAME && *bi != 0) {
name.c[name.l] = *bi;
bi++;
name.l++;
}
if (*bi == '$') {
token = STRINGVAR;
bi++;
}
whitespaces();
if (token == VARIABLE && *bi == '(' ) {
token = ARRAYVAR;
}
/* the new code filling the name variable directly, will be used in the entire code soon */
name.token = token;
if (DEBUG) debugtoken();
return;
}
#else
if (l == 1 || l == 2) {
token = VARIABLE;
name.l = 0;
name.c[0] = *bi;
name.c[1] = 0;
bi++;
if ((*bi >= '0' && *bi <= '9') || (*bi >= 'A' && *bi <= 'Z') || *bi == '_' ) {
name.c[1] = *bi;
bi++;
}
if (*bi == '$') {
token = STRINGVAR;
bi++;
}
whitespaces();
if (token == VARIABLE && *bi == '(' ) {
token = ARRAYVAR;
}
/* the new code filling the name variable directly, will be used in the entire code soon */
name.token = token;
if (DEBUG) debugtoken();
return;
}
#endif
/* other single characters are parsed and stored */
token = *bi;
bi++;
if (DEBUG) debugtoken();
return;
}
/*
Layer 1 - program editor
Editing the program, the structure of a line is
LINENUMBER linenumber(2 or more bytes) token(n bytes)
store* stores something to memory
get* retrieves information
No matter how long number_t is in the C implementation
we pack into bytes, this is clumsy but portable
the store and get commands all operate on here
and advance it
storetoken() operates on the variable top.
We always append at the end and then sort.
gettoken() operate on the variable here
which will also be the key variable in run mode.
tokens are stored including their payload.
This group of functions changes global states and
cannot be called at program runtime with saving
the relevant global variable to the stack.
*/
/*
check if we still have memory left, on RAM only systems we make
sure that we don't hit himem. On systems with EEPROM program storage we make
sure that we stay within the EEPROM range.
*/
char nomemory(number_t b) {
#ifndef EEPROMMEMINTERFACE
if (top >= himem - b) return 1; else return 0;
#else
if (top >= elength() - eheadersize - b) return 1; else return 0;
#endif
}
/* store a token - check free memory before changing anything */
void storetoken() {
int i;
switch (token) {
case LINENUMBER:
if (nomemory(addrsize + 1)) break;
memwrite2(top++, token);
setaddress(top, memwrite2, ax);
top += addrsize;
return;
case NUMBER:
if (nomemory(numsize + 1)) break;
memwrite2(top++, token);
setnumber(top, memwrite2, x);
top += numsize;
return;
case ARRAYVAR:
case VARIABLE:
case STRINGVAR:
if (nomemory(sizeof(name_t))) break;
memwrite2(top++, token);
top = setname_pgm(top, &name);
return;
case STRING:
i = sr.length;
if (nomemory(i + 2)) break;
memwrite2(top++, token);
memwrite2(top++, i);
while (i > 0) {
memwrite2(top++, *sr.ir++);
i--;
}
return;
default:
if (token >= -127) { /* the good old code with just one byte token */
if (nomemory(1)) break;
memwrite2(top++, token);
} else {
#ifdef HASLONGTOKENS
if (nomemory(2)) break; /* this is the two byte token extension */
memwrite2(top++, TEXT1);
memwrite2(top++, token + 255);
#endif
}
return;
}
}
/*
wrappers around mem access in genereal
memread is used only in the token stream, it reads from a stream
read only. If run is done from eeprom then bytes are taken from this
stream, this would also be the place to implement direct run from
another device like a file system or embedded programs on flash.
Only the token stream uses memread.
memread2 and memwrite2 always go to ram. They are read/write. Variables and
the program editor uses these functions.
currently only the SPIRAM and the EEPROM direct edit interface is implemented.
This is handled in the runtime library.
USEMEMINTERFACE is the macro to control this.
The POSIX code has a test interface for SPIRAM as a dummy.
*/
#ifndef USEMEMINTERFACE
mem_t memread(address_t a) {
if (st != SERUN) {
return mem[a];
} else {
return eread(a + eheadersize);
}
}
mem_t memread2(address_t a) {
return mem[a];
}
void memwrite2(address_t a, mem_t c) {
mem[a] = c;
}
#else
#if defined(SPIRAMINTERFACE) || defined(SPIRAMSIMULATOR)
mem_t memread(address_t a) {
if (st != SERUN) {
return spiram_robufferread(a);
} else {
return eread(a + eheadersize);
}
}
mem_t memread2(address_t a) {
return spiram_rwbufferread(a);
}
void memwrite2(address_t a, mem_t c) {
spiram_rwbufferwrite(a, c);
}
#else
#ifdef EEPROMMEMINTERFACE
mem_t memread(address_t a) {
if (a < elength() - eheadersize) return eread(a + eheadersize); else return mem[a - (elength() - eheadersize)];
}
mem_t memread2(address_t a) {
return memread(a);
}
void memwrite2(address_t a, mem_t c) {
if (a < elength() - eheadersize) eupdate(a + eheadersize, c); else mem[a - (elength() - eheadersize)] = c;
}
#endif
#endif
#endif
/* get a token from memory */
void gettoken() {
stringlength_t i;
/* if we have reached the end of the program, EOL is always returned
we don't rely on mem having a trailing EOL */
if (here >= top) {
token = EOL;
return;
}
/* if we have no data type we are done reading just one byte */
token = memread(here++);
name.token = token;
/* if there are multibyte tokens, get the next byte and construct a token value <-127 */
#ifdef HASLONGTOKENS
if (token == TEXT1) {
token = memread(here++) - 255;
}
#endif
/* otherwise we check for the argument */
switch (token) {
case LINENUMBER:
ax = getaddress(here, memread);
here += addrsize;
break;
case NUMBER:
x = getnumber(here, memread);
here += numsize;
break;
case ARRAYVAR:
case VARIABLE:
case STRINGVAR:
here = getname(here, &name, memread);
name.token = token;
break;
case STRING:
sr.length = (unsigned char)memread(here++);
/*
if we run from EEPROM, the input buffer is used to get string constants.
if we run on a system with real memory, we produce a mem pointer
otherwise the caller has to handle strings through the address (SPIRAM systems)
*/
if (st == SERUN) {
for (i = 0; i < sr.length; i++) ibuffer[i] = memread(here + i);
sr.ir = ibuffer;
} else {
#ifndef USEMEMINTERFACE
sr.ir = (char*)&mem[here];
#else
sr.ir = 0;
#endif
}
sr.address = here;
here += sr.length;
}
}
/* goto the first line of a program */
void firstline() {
if (top == 0) {
ax = 0;
return;
}
here = 0;
gettoken();
}
/* goto the next line, search forward */
void nextline() {
while (here < top) {
gettoken();
if (token == LINENUMBER) return;
if (here >= top) {
here = top;
ax = 0;
return;
}
}
}
/*
the line cache mechanism, useful for large codes.
addlinecache does not test if the line already exist because it
assumes that findline calls it only if a new line is to be stored
the LINECACHE size depends on the architecture.
*/
#if defined(LINECACHESIZE) && LINECACHESIZE>0
const unsigned char linecachedepth = LINECACHESIZE;
typedef struct {
address_t l;
address_t h;
} linecacheentry;
linecacheentry linecache[LINECACHESIZE];
unsigned char linecachehere = 0;
void clrlinecache() {
unsigned char i;
for (i = 0; i < linecachedepth; i++) linecache[i].l = linecache[i].h = 0;
linecachehere = 0;
}
void addlinecache(address_t l, address_t h) {
linecache[linecachehere].l = l;
linecache[linecachehere].h = h;
linecachehere = (linecachehere + 1) % linecachedepth;
}
address_t findinlinecache(address_t l) {
unsigned char i;
for (i = 0; i < linecachedepth && linecache[i].l != 0; i++) {
if (linecache[i].l == l) return linecache[i].h;
}
return 0;
}
#else
void clrlinecache() {}
void addlinecache(address_t l, address_t h) {}
address_t findinlinecache(address_t l) {
return 0;
}
#endif
/* find a line, look in cache then search from the beginning
x is used as the valid line number once a line is found
hence x must be global
(this is the logic of the gettoken mechanism)
*/
void findline(address_t l) {
address_t a;
/* we know it already, here to advance */
if ((a = findinlinecache(l))) {
here = a;
token = LINENUMBER;
ax = l;
return;
}
/* we need to search */
here = 0;
while (here < top) {
gettoken();
if (token == LINENUMBER && ax == l ) {
/* now that we know we cache */
addlinecache(l, here);
return;
}
}
error(ELINE);
}
/* finds the line of a location */
address_t myline(address_t h) {
address_t l = 0;
address_t l1 = 0;
address_t here2;
here2 = here;
here = 0;
gettoken();
while (here < top) {
if (token == LINENUMBER) {
l1 = l;
l = ax;
}
if (here >= h) break;
gettoken();
}
here = here2;
if (token == LINENUMBER)
return l1;
else
return l;
}
/*
Move a block of storage beginng at b ending at e
to destination d. No error handling here!!
*/
void moveblock(address_t b, address_t l, address_t d) {
address_t i;
if (d + l > himem) {
error(EOUTOFMEMORY);
return;
}
if (l < 1) return;
if (b < d) for (i = l; i > 0; i--) memwrite2(d + i - 1, memread2(b + i - 1));
else for (i = 0; i < l; i++) memwrite2(d + i, memread2(b + i));
}
/* zero a block of memory */
void zeroblock(address_t b, address_t l) {
address_t i;
if (b + l > himem) {
error(EOUTOFMEMORY);
return;
}
if (l < 1) return;
for (i = 0; i < l + 1; i++) memwrite2(b + i, 0);
}
/*
Line editor:
stage 1: no matter what the line number is - store at the top
remember the location in here.
stage 2: see if it is only an empty line - try to delete this line
stage 3: calculate lengthes and free memory and make room at the
appropriate place
stage 4: copy to the right place
Very fragile code, con't change if you don't have to
zeroblock statements commented out after EOL code was fixed
*/
#ifdef DEBUG
/* diagnosis function */
void diag() {
outsc("top, here, y and x\n");
outnumber(top); outspc();
outnumber(here); outspc();
outcr();
}
#endif
void storeline() {
const index_t lnlength = addrsize + 1;
index_t linelength;
number_t newline;
address_t here2, here3;
address_t t1, t2;
address_t y;
/* the data pointers becomes invalid once the code has been changed */
clrdata();
/* line cache is invalid on line storage */
clrlinecache();
if (DEBUG) {
outsc("storeline ");
outnumber(ax);
outsc(" : ");
outsc(ibuffer);
outcr();
}
/*
stage 1: append the line at the end of the memory,
remember the line number on the stack and the old top in here
*/
t1 = ax;
here = top;
newline = here;
token = LINENUMBER;
do {
storetoken();
if (er != 0 ) {
top = newline;
here = 0;
return;
}
nexttoken();
} while (token != EOL);
ax = t1; /* recall the line number */
linelength = top - here; /* calculate the number of stored bytes */
/*
stage 2: check if only a linenumber stored - then delete this line
*/
if (linelength == (lnlength)) {
top -= (lnlength);
findline(ax);
if (er) return;
y = here - lnlength;
nextline();
here -= lnlength;
if (ax != 0) {
moveblock(here, top - here, y);
top = top - (here - y);
} else {
top = y;
}
return;
}
/*
stage 3, a nontrivial line with linenumber x is to be stored
try to find it first by walking through all lines
*/
else {
y = ax;
here2 = here;
here = lnlength;
nextline();
/* there is no nextline after the first line, we are done */
if (ax == 0) return;
/* go back to the beginning */
here = 0;
here2 = 0;
while (here < top) {
here3 = here2;
here2 = here;
nextline();
if (ax > y) break;
}
/*
at this point y contains the number of the line to be inserted
x contains the number of the first line with a higher line number
or 0 if the line is to be inserted at the end
here points to the following line and here2 points to the previous line
*/
if (ax == 0) {
here = here3 - lnlength;
gettoken();
if (token == LINENUMBER && ax == y) { // we have a double line at the end
here2 -= lnlength;
here -= lnlength;
moveblock(here2, linelength, here);
top = here + linelength;
}
return;
}
here -= lnlength;
t1 = here;
here = here2 - lnlength;
t2 = here;
gettoken();
if (ax == y) { /* the line already exists and has to be replaced */
here2 = t2; /* this is the line we are dealing with */
here = t1; /* this is the next line */
y = here - here2; /* the length of the line as it is */
if (linelength == y) { /* no change in line length */
moveblock(top - linelength, linelength, here2);
top = top - linelength;
} else if (linelength > y) { /* the new line is longer than the old one */
moveblock(here, top - here, here + linelength - y);
here = here + linelength - y;
top = top + linelength - y;
moveblock(top - linelength, linelength, here2);
top = top - linelength;
} else { /* the new line is short than the old one */
moveblock(top - linelength, linelength, here2);
top = top - linelength;
moveblock(here, top - here, here2 + linelength);
top = top - y + linelength;
}
} else { /* the line has to be inserted in between */
here = t1;
moveblock(here, top - here, here + linelength);
moveblock(top, linelength, here);
}
}
}
/*
Layer 1 - the code in this section calculates an expression
with a recursive descent algorithm
all function use the stack to pass values back. We use the
Backus-Naur form of basic from here https://rosettacode.org/wiki/BNF_Grammar
implementing a C style logical expression model
*/
/* the terminal symbol it ends a statement list - ELSE is one too as it ends a statement list */
char termsymbol() {
return (token == LINENUMBER || token == ':' || token == EOL || token == TELSE);
}
/* a little helpers - one token expect */
char expect(token_t t, mem_t e) {
nexttoken();
if (token != t) {
error(e);
return 0;
} else return 1;
}
/* a little helpers - expression expect */
char expectexpr() {
nexttoken();
expression();
if (er != 0) return 0; else return 1;
}
/* parses a list of expression, this may be recursive! */
void parsearguments() {
short argsl;
/* begin counting */
argsl = 0;
/* having 0 args at the end of a command is legal */
if (!termsymbol()) {
/* list of expressions separated by commas */
do {
expression();
if (er != 0) break;
argsl++;
if (token == ',') nexttoken(); else break;
} while (1);
}
/* because of the recursion ... */
args = argsl;
}
/* expect exactly n arguments */
void parsenarguments(char n) {
parsearguments();
if (args != n) error(EARGS);
}
/* counts and parses the number of arguments given in brakets, this function
should not advance to the next token because it is called in factor */
void parsesubscripts() {
blocation_t l;
args = 0;
if (DEBUG) {
outsc("** in parsesubscripts "); outcr();
bdebug("token ");
}
/* remember where we where */
pushlocation(&l);
/* parsesubscripts is called directly after the object in question, it does
nexttoken() itself now */
nexttoken();
/* if we have no bracket here, we return with zero */
if (token != '(') {
poplocation(&l);
return;
}
nexttoken();
/* if () we return also with -1 */
#ifdef HASMULTIDIM
if (token == ')') {
args = -1;
return;
}
#endif
/* now we are ready to parse a set of arguments */
parsearguments();
if (!USELONGJUMP && er) return;
if (token != ')') {
error(EARGS); /* we return with ) as a last token on success */
return;
}
/* we end with the ) still as active token */
}
/* parse a function argument ae is the number of
expected expressions in the argument list, parsesubscripts
should not avance precisely because it is used in factor */
void parsefunction(void (*f)(), short ae) {
parsesubscripts();
if (!USELONGJUMP && er) return;
if (args == ae) f(); else error(EARGS);
}
/* helper function in the recursive decent parser */
void parseoperator(void (*f)()) {
mem_t u = 1;
nexttoken();
/* unary minuses in front of an operator are consumed once! */
if (token == '-') {
u = -1;
nexttoken();
}
/* the operator */
f();
if (er != 0 ) return;
y = pop();
if (u == -1) y = -y;
x = pop();
}
/*
ABS absolute value
*/
void xabs() {
number_t x;
if ((x = pop()) < 0) {
x = -x;
}
push(x);
}
/*
SGN evaluates the sign
*/
void xsgn() {
number_t x;
x = pop();
if (x > 0) x = 1;
if (x < 0) x = -1;
push(x);
}
/*
PEEK on an arduino, negative values of peek address
the EEPROM range -1 .. -1024 on an UNO
*/
void xpeek() {
number_t a;
/* get the argument from the stack because this is a function only */
a = pop();
/* the memory and EEPROM range */
if (a >= 0 && a <= memsize)
push(memread2(a));
else if (a < 0 && -a <= elength())
push(eread(-a - 1));
else {
error(EORANGE);
return;
}
}
/*
MAP Arduino map function, we always cast to long, this
makes it potable for various integer sizes and the float.
*/
void xmap() {
long v, in_min, in_max, out_min, out_max;
out_max = pop();
out_min = pop();
in_max = pop();
in_min = pop();
v = pop();
push((v - in_min) * (out_max - out_min) / (in_max - in_min) + out_min);
}
/*
RND very basic random number generator with constant seed in 16 bit
for float systems, use glibc parameters https://en.wikipedia.org/wiki/Linear_congruential_generator
*/
void xrnd() {
number_t r;
mem_t base = randombase;
/* the argument of the RND() function */
r = pop();
/* this is the microsoft mode, argument <0 resets the sequence, 0 always the same number, > 1 a number between 0 and 1 */
if (randombase < 0) {
base = 0;
if (r < 0) {
rd = -r;
r = 1;
} else if (r == 0) {
r = 1;
goto pushresult;
} else {
r = 1;
}
}
/* this is the congruence */
#ifndef HASFLOAT
/* the original 16 bit congruence, the & is needed to make it work for all kinds of ints */
rd = (31421 * rd + 6927) & 0xffff;
#else
/* glibc parameters */
rd = (110351245 * rd + 12345) & 0x7fffffff;
#endif
pushresult:
/* the result is calculated with the right modulus */
#ifndef HASFLOAT
if (r >= 0)
push((unsigned long)rd * r / 0x10000 + base);
else
push((unsigned long)rd * r / 0x10000 + 1 - base);
#else
if (r >= 0)
push(rd * r / 0x80000000 + base);
else
push(rd * r / 0x80000000 + 1 - base);
#endif
}
#ifndef HASFLOAT
/*
SQR - a very simple approximate square root formula
for integers, for floats we use the library
*/
void sqr() {
number_t t, r;
number_t l = 0;
r = pop();
t = r;
while (t > 0) {
t >>= 1;
l++;
}
l = l / 2;
t = 1;
t <<= l;
do {
l = t;
t = (t + r / t) / 2;
} while (abs(t - l) > 1);
push(t);
}
#else
void sqr() {
push(sqrt(pop()));
}
#endif
/*
POW(X, N) evaluates powers
*/
/* this function is called by POW(a, c) in BASIC */
void xpow() {
number_t n;
number_t a;
n = pop();
a = pop();
push(bpow(a, n));
}
/* while this is needed by ^*/
number_t bpow(number_t x, number_t y) {
#ifdef HASFLOAT
return pow(x, y);
#else
number_t r;
address_t i;
r = 1;
if (y >= 0) for (i = 0; i < y; i++) r *= x;
else r = 0;
return r;
#endif
}
/*
the reimplementation of parsestringvar, this code uses a lhsobject
to store the data in, which is somehow more natural with the new code.
The need to handle substring and no substring situations makes thing
complex.
A plain string has the format A$.
A substringed string has the format A$(i) or A$(i,j).
A string array has the format A$()(i2), A$(i)(i2), A$(i,j)(i2).
In the Microsoft world with substringmode==0 we only have
A$, A$(i2).
All this is distiguished here.
*/
void parsestringvar(string_t* strp, lhsobject_t* lhs) {
#ifdef HASAPPLE1
blocation_t l;
address_t temp;
/* remember the variable name and prep the indices */
copyname(&lhs->name, &name);
lhs->i = 1; /* we start at 1 */
lhs->j = arraylimit; /* we assume a string array of length 1, all simple strings are like this */
lhs->i2 = 0; /* we want the full string length */
lhs->ps = 1; /* we deal with a pure string */
/* remember the location */
pushlocation(&l);
/* and inspect the (first) brackets */
parsesubscripts();
if (!USELONGJUMP && er) return;
if (DEBUG) {
outsc("** in parsestringvar ");
outnumber(args);
outsc(" arguments \n");
}
/* do we deal with a pure unindexed string or something more complicated */
if (args == 0) {
/* pure string, we rewind and are done here */
poplocation(&l);
} else if (!substringmode) {
/* we have no substring interpretation hence the brackets can only be one array index */
if (args == 1) lhs->j = pop(); else {
error(EORANGE);
return;
}
} else {
/* not a pure string */
lhs->ps = 0;
/* we are in the substring world here */
if (args == 2) {
lhs->i2 = popaddress(); /* A$(i,j) */
args--;
}
if (!USELONGJUMP && er) return;
if (args == 1) {
lhs->i = popaddress(); /* A$(i) */
}
if (!USELONGJUMP && er) return;
if (args == -1) {} /* A$(), ignore */
/* here we have parsed a full substring and remember where we are and look forward*/
pushlocation(&l);
nexttoken();
if (token == '(') {
/* a second pair of braces is coming, we parse an array index */
nexttoken();
expression();
if (!USELONGJUMP && er) return;
if (token != ')') {
error(EUNKNOWN);
return;
}
lhs->j = popaddress();
if (!USELONGJUMP && er) return;
} else
poplocation(&l);
}
/* in pure parse mode we end here. This is used for the lefthandside code */
if (!strp) return;
/* try to get the string */
getstring(strp, &lhs->name, lhs->i, lhs->j);
if (!USELONGJUMP && er) return;
/* look what we do with the upper index */
if (!lhs->i2) lhs->i2 = strp->length;
if (DEBUG) {
outsc("** in parsestringvar lower is "); outnumber(lhs->i); outcr();
outsc("** in parsestringvar upper is "); outnumber(lhs->i2); outcr();
outsc("** in parsestringvar array_index is "); outnumber(lhs->j); outcr();
}
/* find the length */
if (lhs->i2 - lhs->i + 1 > 0) strp->length = lhs->i2 - lhs->i + 1; else strp->length = 0;
/* done */
if (DEBUG) {
outsc("** in parsestringvar, length ");
outnumber(strp->length);
outsc(" from "); outnumber(lhs->i); outspc(); outnumber(lhs->i2);
outcr();
}
/* restore the name */
name = lhs->name;
#else
return;
#endif
}
/*
stringvalue(string_t*) evaluates a string value, return 0 if there is no string,
1 if there is a string. The pointer contains all the data needed to process the string.
In STR all number bases are allowed now.
*/
char stringvalue(string_t* strp) {
address_t k, l;
address_t i;
token_t t;
mem_t args = 1;
lhsobject_t lhs;
#ifdef HASNUMSYSTEM
mem_t base = 10;
number_t n;
#endif
if (DEBUG) outsc("** entering stringvalue \n");
/* make sure everything is nice and clean */
strp->address = 0;
strp->arraydim = 0;
strp->length = 0;
strp->strdim = 0;
strp->ir = 0;
switch (token) {
case STRING:
/* sr has the string information from gettoken and nexttoken*/
strp->ir = sr.ir;
strp->length = sr.length;
strp->address = sr.address;
break;
#ifdef HASAPPLE1
case STRINGVAR:
parsestringvar(strp, &lhs);
break;
case TSTR:
nexttoken();
if (token == '$') nexttoken();
if (token != '(') {
error(EARGS);
return 0;
}
nexttoken();
expression();
if (er != 0) return 0;
#ifdef HASNUMSYSTEM
if (token == ',') {
nexttoken();
expression();
if (er != 0) return 0;
base = pop();
}
n = pop();
#ifdef HASFLOAT
if (base == 10) {
strp->length = writenumber2(sbuffer, n);
} else {
n = floor(n);
strp->length = writenumbern(sbuffer, n, base);
}
#else
strp->length = writenumbern(sbuffer, n, base);
#endif
#else
#ifdef HASFLOAT
strp->length = writenumber2(sbuffer, pop());
#else
strp->length = writenumber(sbuffer, pop());
#endif
#endif
strp->ir = sbuffer;
if (er != 0) return 0;
if (token != ')') {
error(EARGS);
return 0;
}
break;
#ifdef HASMSSTRINGS
case TCHR:
nexttoken();
if (token == '$') nexttoken();
if (token != '(') {
error(EARGS);
return 0;
}
nexttoken();
expression();
if (er != 0) return 0;
*sbuffer = pop();
strp->ir = sbuffer;
strp->length = 1;
if (token != ')') {
error(EARGS);
return 0;
}
break;
case TRIGHT:
case TMID:
case TLEFT:
t = token;
nexttoken();
if (token == '$') nexttoken();
if (token != '(') {
error(EARGS);
return 0;
}
nexttoken();
if (token != STRINGVAR) {
error(EARGS);
return 0;
}
parsestringvar(strp, &lhs);
if (er != 0) return 0;
k = strp->length; /* the length of the original string variable */
nexttoken();
if (token != ',') {
error(EARGS);
return 0;
}
nexttoken();
expression();
if (er != 0) return 0;
/* all the rest depends on the function */
switch (t) {
case TRIGHT:
l = popaddress();
if (k < l) l = k;
if (strp->address) strp->address = strp->address + (k - l);
if (strp->ir) strp->ir = strp->ir + (k - l);
break;
case TLEFT:
l = popaddress();
if (k < l) l = k;
break;
case TMID:
if (token == ',') {
nexttoken();
expression();
if (er != 0) return 0;
args++;
}
if (args == 1) {
i = popaddress();
l = 0;
if (i <= k) l = k - i + 1;
} else {
l = popaddress();
if (er != 0) return 0;
i = popaddress();
}
if (i == 0) i = 1;
if (i > k) l = 0;
if (k < i + l) l = k - i + 1;
if (l < 0) l = 0;
if (strp->address != 0) strp->address = strp->address + i - 1;
if (strp->ir) strp->ir = strp->ir + i - 1;;
break;
}
strp->length = l;
if (token != ')') {
error(EARGS);
return 0;
}
break;
#endif
#endif
default:
return 0;
}
return 1;
}
/*
(numerical) evaluation of a string expression, used for
comparison and for string rightvalues as numbers
the token rewind here is needed as streval is called in
factor - no factor function should nexttoken
*/
void streval() {
token_t t;
address_t k;
string_t s1, s2;
char* ir;
address_t a;
blocation_t l;
/* is the right side of the expression a string */
if (!stringvalue(&s1)) {
error(EUNKNOWN);
return;
}
if (!USELONGJUMP && er) return;
if (DEBUG) {
outsc("** in streval first string");
outcr();
}
/* get ready for rewind to this location */
pushlocation(&l);
t = token;
/* is the next token a operator, hence we need to compare two strings? */
nexttoken();
if (token != '=' && token != NOTEQUAL) {
/* if not, rewind one token and evaluate the string as a boolean */
poplocation(&l);
token = t;
/* a zero length string evaluates to zero else to the first character */
if (s1.length == 0) push(0); else {
if (s1.ir) push(s1.ir[0]);
else if (s1.address) push(memread2(s1.address));
else error(EGENERAL);
}
return;
}
/* remember which operator we use */
t = token;
/* questionable !! */
nexttoken();
if (DEBUG) {
outsc("** in streval second string"); outcr();
debugtoken(); outcr();
}
/* get the second string */
if (!stringvalue(&s2)) {
error(EUNKNOWN);
return;
}
if (!USELONGJUMP && er) return;
if (DEBUG) {
outsc("** in streval result: ");
outnumber(x);
outcr();
}
/* different length means unequal */
if (s2.length != s1.length) goto neq;
/* and a different character somewhere is also unequal */
#ifdef USEMEMINTERFACE
if (s1.ir && s2.ir)
for (k = 0; k < s1.length; k++) {
if (s1.ir[k] != s2.ir[k]) goto neq;
}
else if (s1.address && s2.address)
for (k = 0; k < s1.length; k++) {
if (memread2(s1.address + k) != memread2(s2.address + k)) goto neq;
}
else {
if (s1.address) {
a = s1.address;
ir = s2.ir;
} else {
a = s2.address;
ir = s1.ir;
}
for (k = 0; k < s1.length; k++) {
if (memread2(a + k) != ir[k] ) goto neq;
}
}
#else
for (k = 0; k < s1.length; k++) if (s1.ir[k] != s2.ir[k]) goto neq;
#endif
/* which operator did we use */
if (t == '=') push(booleanmode); else push(0);
return;
neq:
if (t == '=') push(0); else push(booleanmode);
return;
}
#ifdef HASFLOAT
/*
floating point arithmetic
SIN, COS, TAN, ATAN, LOG, EXP, INT
INT is always there and is nop in integer BASICs
no handling of floating point errors yet.
*/
void xsin() {
push(sin(pop()));
}
void xcos() {
push(cos(pop()));
}
void xtan() {
push(tan(pop()));
}
void xatan() {
push(atan(pop()));
}
void xlog() {
push(log(pop()));
}
void xexp() {
push(exp(pop()));
}
void xint() {
push(floor(pop()));
}
#else
void xint() {}
#endif
/* this function does a bitwise compare. It checks if one bit is 1 or 0 and returns
the right BASIC boolean value */
void xbit() {
int a, b;
/* this is slightly unclean as we do no error detection on the range */
b = (int)pop();
a = (int)pop();
/* pushing booleanmode makes sure we have the right kind of true (1 or -1) */
if (a & (1 << b)) push(booleanmode); else push(0);
}
/*
Recursive expression parser functions
factor(); term(); addexpression(); compexpression();
notexpression(); andexpression(); expression()
doing
functions, numbers; *, /, %; +, -; =, <>, =>, <=;
NOT; AND; OR
*/
/*
factor() - contrary to all other function
nothing here should end with a new token - this is handled
in factors calling function
evaluates constants, variables and all functions
*/
/* helpers of factor - array access */
void factorarray() {
lhsobject_t object;
number_t v;
/* remember the variable, because parsesubscript changes this */
copyname(&object.name, &name);
/* parse the arguments */
parsesubscripts();
if (er != 0 ) return;
switch (args) {
case 1:
object.i = popaddress();
if (!USELONGJUMP && er) return;
object.j = arraylimit;
break;
#ifdef HASMULTIDIM
case 2:
object.j = popaddress();
object.i = popaddress();
if (!USELONGJUMP && er) return;
break;
#endif
default:
error(EARGS);
return;
}
array(&object, 'g', &v);
push(v);
}
/* helpers of factor - string length */
void factorlen() {
#ifdef HASAPPLE1
address_t a;
string_t s;
name_t n;
lhsobject_t lhs;
nexttoken();
if ( token != '(') {
error(EARGS);
return;
}
nexttoken();
switch (token) {
case STRING:
push(sr.length);
nexttoken();
break;
case STRINGVAR:
parsestringvar(&s, &lhs);
push(s.length);
nexttoken();
break;
#ifdef HASMSSTRINGS
case TRIGHT:
case TLEFT:
case TMID:
case TCHR:
#endif
case TSTR:
error(EARGS);
return;
default:
expression();
if (!USELONGJUMP && er) return;
n.token = TBUFFER;
a = pop();
n.c[0] = a % 256;
n.c[1] = a / 256;
push(blength(&n));
}
if (!USELONGJUMP && er) return;
if (token != ')') {
error(EARGS);
return;
}
#else
push(0);
#endif
}
/* helpers of factor - the VAL command */
void factorval() {
index_t y;
number_t x;
string_t s;
address_t a;
char *ir;
#define DEBUG 0
mem_t numsys = 0;
nexttoken();
if (token != '(') {
error(EARGS);
return;
}
nexttoken();
if (!stringvalue(&s)) {
error(EUNKNOWN);
return;
}
if (!USELONGJUMP && er) return;
/* the length of the strings consumed */
vlength = 0;
/* get the string if it is in serial memory */
#ifdef USEMEMINTERFACE
if (!s.ir) getstringtobuffer(&s, spistrbuf1, SPIRAMSBSIZE);
#endif
/* generate a 0 terminated string for use with parsenumber */
stringtobuffer(sbuffer, &s);
ir = sbuffer;
if (DEBUG) {
outsc("factorval: ");
outsc(ir);
outcr();
}
/* remove whitespaces */
while (*ir == ' ' || *ir == '\t') {
ir++;
vlength++;
}
/* find a sign */
if (*ir == '-') {
y = -1;
ir++;
vlength++;
} else y = 1;
/* see if we scan integer hex, octal or bin constants, the real scanning is done in parsenumbern */
#ifdef HASNUMSYSTEM
if (*ir == '0' && ( *(ir + 1) == 'x' || *(ir + 1) == 'X' || *(ir + 1) == 'b' || *(ir + 1) == 'B' \
|| *(ir + 1) == 'o' || *(ir + 1) == 'O' )) {
numsys = 1;
}
#endif
if (DEBUG) {
outsc("factorval: ");
outsc(ir);
outsc(" ");
outnumber(y);
outsc(" ");
outnumber(numsys);
outcr();
}
#define DEBUG 0
x = 0;
#ifdef HASFLOAT
#ifdef HASNUMSYSTEM
if (numsys) {
if ((a = parsenumbern(ir, &x)) > 0) {
vlength += a;
ert = 0;
} else {
vlength = 0;
ert = 1;
};
} else {
if ((a = parsenumber2(ir, &x)) > 0) {
vlength += a;
ert = 0;
} else {
vlength = 0;
ert = 1;
};
}
#else
if ((a = parsenumber2(ir, &x)) > 0) {
vlength += a;
ert = 0;
} else {
vlength = 0;
ert = 1;
};
#endif
#else
#ifdef HASNUMSYSTEM
if (numsys) {
if ((a = parsenumbern(ir, &x)) > 0) {
vlength += a;
ert = 0;
} else {
vlength = 0;
ert = 1;
};
} else {
if ((a = parsenumber(ir, &x)) > 0) {
vlength += a;
ert = 0;
} else {
vlength = 0;
ert = 1;
};
}
#else
if ((a = parsenumber(ir, &x)) > 0) {
vlength += a;
ert = 0;
} else {
vlength = 0;
ert = 1;
};
#endif
#endif
push(x * y);
nexttoken();
if (token != ')') {
error(EARGS);
return;
}
}
/* helpers of factor - the INSTR command */
#ifndef HASFULLINSTR
/* this is instring in a single character version, usefull to split strings */
void factorinstr() {
char ch;
address_t a;
string_t s;
nexttoken();
if (token != '(') {
error(EARGS);
return;
}
nexttoken();
if (!stringvalue(&s)) {
error(EUNKNOWN);
return;
}
if (!USELONGJUMP && er) return;
nexttoken();
if (token != ',') {
error(EARGS);
return;
}
nexttoken();
expression();
if (!USELONGJUMP && er) return;
ch = pop();
if (s.address) {
for (a = 1; a <= s.length; a++) {
if (memread2(s.address + a - 1) == ch) break;
}
} else {
for (a = 1; a <= s.length; a++) {
if (s.ir[a - 1] == ch) break;
}
}
if (a > s.length) a = 0;
push(a);
//nexttoken();
if (token != ')') {
error(EARGS);
return;
}
}
#else
/* the full instr command which can compare two strings */
void factorinstr() {
char ch;
address_t a = 1;
address_t i = 1;
string_t search;
string_t s;
nexttoken();
if (token != '(') {
error(EARGS);
return;
}
nexttoken();
/* the search string */
if (!stringvalue(&s)) {
error(EUNKNOWN);
return;
}
if (!USELONGJUMP && er) return;
nexttoken();
if (token != ',') {
error(EARGS);
return;
}
nexttoken();
/* the string to be searched */
if (!stringvalue(&search)) {
error(EUNKNOWN);
return;
}
if (!USELONGJUMP && er) return;
nexttoken();
/* potentially the start value */
if (token == ',') {
nexttoken();
expression();
if (!USELONGJUMP && er) return;
a = popaddress();
if (!USELONGJUMP && er) return;
}
if (token != ')') {
error(EUNKNOWN);
return;
}
/* health check */
if (search.length == 0 || search.length + a > s.length || a == 0) {
push(0);
return;
}
/* go through the search string */
while (i <= search.length) {
/* get one character from the string */
if (search.address) {
ch = memread2(search.address + i - 1);
} else {
ch = search.ir[i - 1];
}
/* search the character */
if (s.address) {
for (; a <= s.length; a++) {
if (memread2(s.address + a - 1) == ch) break;
}
} else {
for (; a <= s.length; a++) {
if ( s.ir[a - 1] == ch ) break;
}
}
/* we haven't found the character until the end of the string */
if (a > s.length) {
a = 0;
break;
}
/* next character */
i += 1;
}
/* how did the search go? a rewind because we were at the end of the search part already */
if (i <= search.length) {
a = 0;
} else {
a = a - search.length + 1;
}
push(a);
}
#endif
/* helpers of factor - the NETSTAT command */
void factornetstat() {
address_t x = 0;
if (netconnected()) x = 1;
if (mqttstate() == 0) x += 2;
push(x);
}
/* helpers of factor - the ASC command, really not needed but for completeness */
void factorasc() {
#ifdef HASAPPLE1
string_t s;
lhsobject_t lhs;
nexttoken();
if ( token != '(') {
error(EARGS);
return;
}
nexttoken();
switch (token) {
case STRING:
if (sr.ir) push(sr.ir[0]); else push(memread2(sr.address));
nexttoken();
break;
case STRINGVAR:
parsestringvar(&s, &lhs);
if (s.length > 0) {
if (s.ir) push(s.ir[0]); else push(memread2(s.address));
} else
push(0);
nexttoken();
break;
default:
error(EARGS);
return;
}
if (!USELONGJUMP && er) return;
if (token != ')') {
error(EARGS);
return;
}
#else
push(0);
#endif
}
void factor() {
if (DEBUG) bdebug("factor\n");
switch (token) {
case NUMBER:
push(x);
break;
case VARIABLE:
push(getvar(&name));
break;
case ARRAYVAR:
factorarray();
break;
case '(':
nexttoken();
expression();
if (er != 0 ) return;
if (token != ')') {
error(EARGS);
return;
}
break;
/* Palo Alto BASIC functions */
case TABS:
parsefunction(xabs, 1);
break;
case TRND:
parsefunction(xrnd, 1);
break;
case TSIZE:
push(himem - top);
break;
/* Apple 1 BASIC functions */
#ifdef HASAPPLE1
case TSGN:
parsefunction(xsgn, 1);
break;
case TPEEK:
parsefunction(xpeek, 1);
break;
case TLEN:
factorlen();
break;
#ifdef HASIOT
case TAVAIL:
parsefunction(xavail, 1);
break;
case TOPEN:
parsefunction(xfopen, 1);
break;
case TSENSOR:
parsefunction(xfsensor, 2);
break;
case TVAL:
factorval();
break;
case TINSTR:
factorinstr();
break;
case TWIRE:
parsefunction(xfwire, 1);
break;
#endif
#ifdef HASERRORHANDLING
case TERROR:
push(erh);
break;
#endif
case THIMEM:
push(himem);
break;
/* Apple 1 string compare code */
case STRING:
case STRINGVAR:
#ifdef HASIOT
case TSTR:
#endif
#ifdef HASMSSTRINGS
case TLEFT:
case TRIGHT:
case TMID:
case TCHR:
#endif
streval();
if (er != 0 ) return;
break;
#endif
/* Stefan's tinybasic additions */
#ifdef HASSTEFANSEXT
case TSQR:
parsefunction(sqr, 1);
break;
case TMAP:
parsefunction(xmap, 5);
break;
case TPOW:
parsefunction(xpow, 2);
break;
#endif
#ifdef HASUSRCALL
case TUSR:
parsefunction(xusr, 2);
break;
#endif
/* Arduino I/O */
#ifdef HASARDUINOIO
case TAREAD:
parsefunction(xaread, 1);
break;
case TDREAD:
parsefunction(xdread, 1);
break;
case TMILLIS:
parsefunction(bmillis, 1);
break;
#ifdef HASPULSE
case TPULSE:
parsefunction(bpulsein, 3);
break;
#endif
case TAZERO:
#if defined(ARDUINO) && defined(A0)
push(A0);
#else
push(0);
#endif
break;
case TLED:
#ifdef LED_BUILTIN
push(LED_BUILTIN);
#else
push(0);
#endif
break;
#endif
/* mathematical functions in case we have float */
#ifdef HASFLOAT
case TSIN:
parsefunction(xsin, 1);
break;
case TCOS:
parsefunction(xcos, 1);
break;
case TTAN:
parsefunction(xtan, 1);
break;
case TATAN:
parsefunction(xatan, 1);
break;
case TLOG:
parsefunction(xlog, 1);
break;
case TEXP:
parsefunction(xexp, 1);
break;
#endif
/* int is always present to make programs compatible */
case TINT:
parsefunction(xint, 1);
break;
#ifdef HASDARTMOUTH
case TFN:
xfn(0);
break;
/* an arcane feature, DATA evaluates to the data record number */
case TDATA:
push(datarc);
break;
#endif
#ifdef HASDARKARTS
case TMALLOC:
parsefunction(xmalloc, 2);
break;
case TFIND:
xfind();
break;
#endif
#ifdef HASIOT
case TNETSTAT:
factornetstat();
break;
#endif
#ifdef HASMSSTRINGS
case TASC:
factorasc();
break;
#endif
case TBIT:
parsefunction(xbit, 2);
break;
/* unknown function */
default:
error(EUNKNOWN);
return;
}
}
/* this is how the power operator ^ is handled */
#ifdef POWERRIGHTTOLEFT
/* the recursive version */
void power() {
if (DEBUG) bdebug("power\n");
factor();
if (!USELONGJUMP && er) return;
nexttoken();
if (DEBUG) bdebug("in power\n");
if (token == '^') {
parseoperator(power);
if (!USELONGJUMP && er) return;
push(bpow(x, y));
}
if (DEBUG) bdebug("leaving power\n");
}
#else
/* the left associative version */
void power() {
if (DEBUG) bdebug("power\n");
factor();
if (!USELONGJUMP && er) return;
nextpower:
nexttoken();
if (DEBUG) bdebug("in power\n");
if (token == '^') {
parseoperator(factor);
push(bpow(x, y));
goto nextpower;
}
if (DEBUG) bdebug("leaving power\n");
}
#endif
/*
* term() evaluates powers, multiplication, division and mod.
* There are two versions, one with a power operator ^ and one without.
*/
#ifdef HASPOWER
void term() {
if (DEBUG) bdebug("term\n");
power();
if (!USELONGJUMP && er) return;
nextfactor:
if (DEBUG) bdebug("in term\n");
if (token == '*') {
parseoperator(power);
if (!USELONGJUMP && er) return;
push(x * y);
goto nextfactor;
} else if (token == '/') {
parseoperator(power);
if (!USELONGJUMP && er) return;
if (y != 0)
#ifndef HASFLOAT
push(x / y);
#else
if (forceint) push((int)x / (int)y); else push(x / y);
#endif
else {
error(EDIVIDE);
return;
}
goto nextfactor;
} else if (token == '%') {
parseoperator(power);
if (!USELONGJUMP && er) return;
if (y != 0)
#ifndef HASFLOAT
push(x % y);
#else
push((int)x % (int)y);
#endif
else {
error(EDIVIDE);
return;
}
goto nextfactor;
} else if (token == TSHL) {
parseoperator(power);
if (!USELONGJUMP && er) return;
push((int)x << (int)y);
goto nextfactor;
} else if (token == TSHR) {
parseoperator(power);
if (!USELONGJUMP && er) return;
push((int)x >> (int)y);
goto nextfactor;
}
if (DEBUG) bdebug("leaving term\n");
}
#else
void term() {
if (DEBUG) bdebug("term\n");
factor();
if (!USELONGJUMP && er) return;
nextfactor:
nexttoken();
if (DEBUG) bdebug("in term\n");
if (token == '*') {
parseoperator(factor);
if (!USELONGJUMP && er) return;
push(x * y);
goto nextfactor;
} else if (token == '/') {
parseoperator(factor);
if (!USELONGJUMP && er) return;
if (y != 0)
#ifndef HASFLOAT
push(x / y);
#else
if (forceint) push((int)x / (int)y); else push(x / y);
#endif
else {
error(EDIVIDE);
return;
}
goto nextfactor;
} else if (token == '%') {
parseoperator(factor);
if (!USELONGJUMP && er) return;
if (y != 0)
#ifndef HASFLOAT
push(x % y);
#else
push((int)x % (int)y);
#endif
else {
error(EDIVIDE);
return;
}
goto nextfactor;
} else if (token == TSHL) {
parseoperator(factor);
if (!USELONGJUMP && er) return;
push((int)x << (int)y);
goto nextfactor;
} else if (token == TSHR) {
parseoperator(factor);
if (!USELONGJUMP && er) return;
push((int)x >> (int)y);
goto nextfactor;
}
if (DEBUG) bdebug("leaving term\n");
}
#endif
/* add and subtract */
void addexpression() {
if (DEBUG) bdebug("addexp\n");
if (token != '+' && token != '-') {
term();
if (!USELONGJUMP && er) return;
} else {
push(0);
}
nextterm:
if (token == '+' ) {
parseoperator(term);
if (!USELONGJUMP && er) return;
push(x + y);
goto nextterm;
} else if (token == '-') {
parseoperator(term);
if (!USELONGJUMP && er) return;
push(x - y);
goto nextterm;
}
}
/* comparisions */
void compexpression() {
if (DEBUG) bdebug("compexp\n");
addexpression();
if (!USELONGJUMP && er) return;
switch (token) {
case '=':
parseoperator(compexpression);
if (!USELONGJUMP && er) return;
#ifndef HASFLOAT
push(x == y ? booleanmode : 0);
#else
if (fabs(x - y) <= epsilon) push(booleanmode); else push(0);
#endif
break;
case NOTEQUAL:
parseoperator(compexpression);
if (!USELONGJUMP && er) return;
#ifndef HASFLOAT
push(x != y ? booleanmode : 0);
#else
if (fabs(x - y) > epsilon) push(booleanmode); else push(0);
#endif
break;
case '>':
parseoperator(compexpression);
if (!USELONGJUMP && er) return;
push(x > y ? booleanmode : 0);
break;
case '<':
parseoperator(compexpression);
if (!USELONGJUMP && er) return;
push(x < y ? booleanmode : 0);
break;
case LESSEREQUAL:
parseoperator(compexpression);
if (!USELONGJUMP && er) return;
push(x <= y ? booleanmode : 0);
break;
case GREATEREQUAL:
parseoperator(compexpression);
if (!USELONGJUMP && er) return;
push(x >= y ? booleanmode : 0);
break;
}
}
#ifdef HASAPPLE1
/* boolean NOT */
void notexpression() {
if (DEBUG) bdebug("notexp\n");
if (token == TNOT) {
nexttoken();
expression();
if (!USELONGJUMP && er) return;
if (booleanmode == -1) push(~(short)pop());
else if (pop() == 0) push(1); else push(0);
} else
compexpression();
}
/* boolean AND and at the same time bitwise */
void andexpression() {
if (DEBUG) bdebug("andexp\n");
notexpression();
if (!USELONGJUMP && er) return;
if (token == TAND) {
parseoperator(expression);
if (!USELONGJUMP && er) return;
push((short)x & (short)y);
}
}
/* expression function and boolean OR at the same time bitwise !*/
void expression() {
if (DEBUG) bdebug("exp\n");
andexpression();
if (!USELONGJUMP && er) return;
if (token == TOR) {
parseoperator(expression);
if (!USELONGJUMP && er) return;
push((short)x | (short)y);
}
}
#else
/* expression function simplified */
void expression() {
if (DEBUG) bdebug("exp\n");
compexpression();
if (!USELONGJUMP && er) return;
if (token == TOR) {
parseoperator(expression);
if (!USELONGJUMP && er) return;
push((short)x | (short)y);
}
}
#endif
/*
Layer 2 - The commands and their helpers
Palo Alto BASIC languge set - PRINT, LET, INPUT, GOTO, GOSUB, RETURN,
IF, FOR, TO, NEXT, STEP, BREAK, STOP, END, LIST, NEW, RUN, REM
BREAK is not Palo ALto but fits here, eEND is identical to STOP.
*/
/*
PRINT command, extended by many features like file, wire, mqtt and radio i/o.
TAB added as part of the PRINT statement with C64 compatibility.
*/
void xprint() {
char semicolon = 0;
char oldod;
char modifier = 0;
string_t s;
stringlength_t i;
form = 0;
oldod = od;
nexttoken();
processsymbol:
/* at the end of a print statement, do we need a newline, restore the defaults */
if (termsymbol()) {
if (!semicolon) outcr();
od = oldod;
form = 0;
return;
}
semicolon = 0;
/* output a string if we found it */
if (stringvalue(&s)) {
if (!USELONGJUMP && er) return;
/* buffer must be used here for machine code to work */
#ifdef USEMEMINTERFACE
if (!s.ir) getstringtobuffer(&s, spistrbuf1, SPIRAMSBSIZE);
#endif
outs(s.ir, s.length);
nexttoken();
goto separators;
}
/* the tab command as part of print */
#ifdef HASMSSTRINGS
if (token == TTAB || token == TSPC) {
xtab();
goto separators;
}
#endif
/* modifiers of the print statement */
if (token == '#' || token == '&') {
modifier = token;
nexttoken();
expression();
if (!USELONGJUMP && er) return;
switch (modifier) {
case '#':
form = pop();
break;
case '&':
od = pop();
break;
}
goto separators;
}
if (token != ',' && token != ';') {
expression();
if (!USELONGJUMP && er) return;
outnumber(pop());
}
/* commas and semicolons, all other symbols are accepted and no error is thrown */
separators:
if (termsymbol()) goto processsymbol;
switch (token) {
case ',':
if (!modifier) outspc();
case ';':
semicolon = 1;
nexttoken();
break;
}
modifier = 0;
goto processsymbol;
}
/*
LET assigment code for various lefthand and righthand side.
lefthandside is a helper function for reuse in other
commands. It determines the address the value is to be
assigned to and whether the assignment target is a
"pure" i.e. subscriptless string expression
assignnumber assigns a number to a given lefthandside
In lefthandside the type of the object is determined and
possible subscripts are parsed.
Variables have no subscripts. The arguments are unchanged.
Arrays may have two subscript which will go to i, j
Strings may have a string subscript, going to i and an array subscript
going to j
String arrays use i2 as the array index.
Note that the role of the variables differs for string array and normal
arrays.
Strings without a subscript i.e. pure strings, set the ps flag
*/
/* the new lefthandsite code */
void lefthandside(lhsobject_t* lhs) {
/* just to provide it for parsestringvar to reuse the righthandside code */
address_t temp;
if (DEBUG) {
outsc("assigning to variable ");
outname(&lhs->name); outspc();
outsc(" type "); outnumber(lhs->name.token);
outcr();
}
/* prep it */
lhs->i = 1;
lhs->i2 = 0;
lhs->j = arraylimit;
lhs->ps = 1;
/* look at the variables and continue parsing */
switch (lhs->name.token) {
case VARIABLE:
nexttoken();
break;
case ARRAYVAR:
parsesubscripts();
if (!USELONGJUMP && er) return;
switch (args) {
case 1:
lhs->i = popaddress();
if (!USELONGJUMP && er) return;
lhs->j = arraylimit;
break;
case 2:
lhs->j = popaddress();
if (!USELONGJUMP && er) return;
lhs->i = popaddress();
if (!USELONGJUMP && er) return;
break;
default:
error(EARGS);
return;
}
nexttoken();
break;
#ifdef HASAPPLE1
case STRINGVAR:
parsestringvar(0, lhs);
nexttoken();
break;
#else /* HASAPPLE1 */
/* here we could implement a string thing for a true Tinybasic */
#endif
default:
error(EUNKNOWN);
return;
}
if (DEBUG) {
outsc("** in assignment lefthandside with (i,j,ps,i2) ");
outnumber(lhs->i); outspc();
outnumber(lhs->j); outspc();
outnumber(lhs->ps); outspc();
outnumber(lhs->i2); outcr();
outsc(" token is "); outputtoken();
outsc(" at "); outnumber(here); outcr();
}
}
/* assign a number to a left hand side we have parsed */
void assignnumber2(lhsobject_t* lhs, number_t x) {
string_t sr;
/* depending on the variable type, assign the value */
switch (lhs->name.token) {
case VARIABLE:
setvar(&lhs->name, x);
break;
case ARRAYVAR:
array(lhs, 's', &x);
break;
#ifdef HASAPPLE1
case STRINGVAR:
/* find the string variable */
getstring(&sr, &lhs->name, lhs->i, lhs->j);
if (!USELONGJUMP && er) return;
/* the first character of the string is set to the number */
if (sr.ir) sr.ir[0] = x; else if (sr.address) memwrite2(ax, x); else error(EUNKNOWN);
/* set the length */
if (lhs->ps)
setstringlength(&lhs->name, 1, lhs->j);
else if (sr.length < lhs->i && lhs->i <= sr.strdim)
setstringlength(&lhs->name, lhs->i, lhs->j);
break;
#endif
}
}
/*
LET - the core assigment function, this is different from other BASICs
*/
void assignment() {
address_t newlength, copybytes;
mem_t s;
index_t k;
char tmpchar; /* for number conversion only */
string_t sr, sl; /* the right and left hand side strings */
/* the lefthandside identifier */
lhsobject_t lhs;
/* this code evaluates the left hand side, we remember the object information first */
copyname(&lhs.name, &name);
lefthandside(&lhs);
if (!USELONGJUMP && er) return;
/* the assignment part */
if (token != '=') {
error(EUNKNOWN);
return;
}
nexttoken();
/* here comes the code for the right hand side, the evaluation depends on the left hand side type */
switch (lhs.name.token) {
/* the lefthandside is a scalar, evaluate the righthandside as a number, even if it is a string */
case VARIABLE:
case ARRAYVAR:
expression();
if (!USELONGJUMP && er) return;
assignnumber2(&lhs, pop());
break;
#ifdef HASAPPLE1
/* the lefthandside is a string variable, try evaluate the righthandside as a stringvalue */
case STRINGVAR:
nextstring:
/* do we deal with a string as righthand side */
s = stringvalue(&sr);
if (!USELONGJUMP && er) return;
/* and then as an expression if it is no string, any number appearing in a string expression terminates the addition loop */
if (!s) {
expression();
if (!USELONGJUMP && er) return;
tmpchar = pop();
sr.length = 1;
sr.ir = &tmpchar;
} else
nexttoken(); /* we do this here because expression also advances, this way we avoid double advance */
if (DEBUG) {
outsc("* assigment stringcode at ");
outnumber(here);
outcr();
}
/* at this point we have a stringvalue with ir2 pointing to the payload and the stack the length
this is either coming from stringvalue or from the expression code */
/* we now process the source string */
/* getstring of the destination */
getstring(&sl, &lhs.name, lhs.i, lhs.j);
if (!USELONGJUMP && er) return;
/* this debug messes up sbuffer hence all functions that use it in stringvalue produce wrong results */
if (DEBUG) {
outsc("* assigment stringcode "); outname(&lhs.name); outcr();
outsc("** assignment source string length "); outnumber(sr.length); outcr();
outsc("** assignment dest string length "); outnumber(sl.length); outcr();
outsc("** assignment dest string dimension "); outnumber(sl.strdim); outcr();
}
/* does the source string fit into the destination if we have no destination second index*/
if ((lhs.i2 == 0) && ((lhs.i + sr.length - 1) > sl.strdim)) {
error(EORANGE);
return;
};
/* if we have a second index, is it in range */
if ((lhs.i2 != 0) && lhs.i2 > sl.strdim) {
error(EORANGE);
return;
};
/* calculate the number of bytes we truely want to copy */
if (lhs.i2 > 0) copybytes = ((lhs.i2 - lhs.i + 1) > sr.length) ? sr.length : (lhs.i2 - lhs.i + 1);
else copybytes = sr.length;
if (DEBUG) {
outsc("** assignment copybytes ");
outnumber(copybytes);
outcr();
}
/* now do the heavy lifting in a seperate function to encasulate buffering */
assignstring(&sl, &sr, copybytes);
/*
classical Apple 1 behaviour is string truncation in substring logic, with
two index destination string we follow another route. We extend the string
for the number of copied bytes
*/
if (lhs.i2 == 0) {
newlength = lhs.i + sr.length - 1;
} else {
if (lhs.i + copybytes > sl.length) newlength = lhs.i + copybytes - 1;
else newlength = sl.length;
}
setstringlength(&lhs.name, newlength, lhs.j);
/*
we have processed one string and copied it fully to the destination
see if there is more to come. For inplace strings this is odd because
one term can change during adding (A$ = B$ + A$).
*/
addstring:
if (token == '+') {
lhs.i = lhs.i + copybytes;
nexttoken();
goto nextstring;
}
break; /* case STRINGVAR */
#endif /* HASAPPLE1 */
} /* switch */
}
/*
Try to copy one string to the other, assumes that getstring did its work
and that copybyte is correct.
BASICs in place strings make this a non trivial exercise as we need to
avoid overwrites.
Another complication is the mixed situation of BASIC memory strings
and C memory strings.
*/
void assignstring(string_t* sl, string_t* sr, stringlength_t copybytes) {
stringlength_t k;
/* if we have a memory model that needs the mem interface, go through the addresses by default
else use just the pointers */
#ifdef USEMEMINTERFACE
/* for a regular string variable as left hand side we know the address */
if (sl->address) {
/* for a regular string variable as a source we need to take care of order */
if (sr->address) {
if (sr->address > sl->address)
for (k = 0; k < copybytes; k++) memwrite2(sl->address + k, memread2(sr->address + k));
else
for (k = 1; k <= copybytes; k++) memwrite2(sl->address + copybytes - k, memread2(sr->address + copybytes - k));
} else {
/* if the right hand side is a special string or a constant things are much simpler */
for (k = 0; k < copybytes; k++) memwrite2(sl->address + k, sr->ir[k]);
}
} else {
/* non regular string variables like @U$ and @T$ are never assignable */
error(EUNKNOWN);
}
#else
/* we just go through the C memory here */
if (sr->ir && sl->ir) {
if (sr->ir > sl->ir)
for (k = 0; k < copybytes; k++) sl->ir[k] = sr->ir[k];
else
for (k = 1; k <= copybytes; k++) sl->ir[copybytes - k] = sr->ir[copybytes - k];
} else {
error(EUNKNOWN);
}
#endif
}
/*
INPUT ["string",] variable [,["string",] variable]
The original version of input only processes simple variables one at a time
and does not support arrays. The code is redudant to assignment and read.
It also does not support comma separated lists of values to be input.
*/
void showprompt() {
outsc("? ");
}
/*
Reimplementation of input using the same pattern as read and print .
*/
void xinput() {
mem_t oldid = id; /* remember the stream on modify */
mem_t prompt = 1; /* determine if we show the prompt */
number_t xv; /* for number conversion with innumber */
/* the identifier of the lefthandside */
lhsobject_t lhs;
address_t maxlen, newlength; /* the maximum length of the string to be read */
int k = 0; /* the result of the number conversion */
string_t s;
char* buffer; /* the buffer we use for input */
address_t bufsize; /* the size of the buffer */
/* depending on the RUN state we use either the input buffer or the string buffer */
/* this ways we can process long inputs in RUN and don't need a lot of memory */
if (st == SRUN || st == SERUN) {
buffer = ibuffer;
bufsize = BUFSIZE;
} else {
buffer = sbuffer;
bufsize = SBUFSIZE;
}
/* get the next token and check what we are dealing with */
nexttoken();
/* modifiers of the input statement (stream) */
if (token == '&') {
if (!expectexpr()) return;
oldid = id;
id = pop();
if (id != ISERIAL || id != IKEYBOARD) prompt = 0;
if (token != ',') {
error(EUNKNOWN);
return;
} else
nexttoken();
}
/* unlike print, form can appear only once in input after the
stream, it controls character counts in wire */
if (token == '#') {
if (!expectexpr()) return;
form = pop();
if (token != ',') {
error(EUNKNOWN);
return;
} else
nexttoken();
}
/* we have a string to be printed to prompt the user */
nextstring:
if (token == STRING && id != IFILE) {
prompt = 0;
#ifdef USEMEMINTERFACE
if (!sr.ir) getstringtobuffer(&sr, spistrbuf1, SPIRAMSBSIZE);
#endif
outs(sr.ir, sr.length);
nexttoken();
}
/* now we check for a variable and parse it */
nextvariable:
if (token == VARIABLE || token == ARRAYVAR || token == STRINGVAR) {
/* check for a valid lefthandside expression */
copyname(&lhs.name, &name);
lefthandside(&lhs);
if (!USELONGJUMP && er) return;
/* which data type do we input */
switch (lhs.name.token) {
case VARIABLE:
case ARRAYVAR:
again:
/* if we have no buffer or are at the end, read it and set cursor k to the beginning */
if (k == 0 || (address_t) buffer[0] < k) {
if (prompt) showprompt();
(void) ins(buffer, bufsize);
k = 1;
}
/* read a number from the buffer and return it, advance the cursor k */
k = innumber(&xv, buffer, k);
/* if we break, end it here */
if (k == -1) {
st = SINT;
token = EOL;
goto resetinput;
}
/* if we have no valid number, ask again */
if (k == 0) {
if (id == ISERIAL || id == IKEYBOARD) {
printmessage(ENUMBER);
outspc();
printmessage(EGENERAL);
outcr();
xv = 0;
k = 0;
goto again;
} else {
ert = 1;
xv = 0;
goto resetinput;
}
}
/* now assign the number */
assignnumber2(&lhs, xv);
/* look if there is a comma coming in the buffer and keep it */
while (k < (address_t) buffer[0] && buffer[k] != 0) {
if (buffer[k] == ',') {
k++;
break;
}
k++;
}
break;
#ifdef HASAPPLE1
case STRINGVAR:
/* the destination address of the lefthandside, on the fly create included */
getstring(&s, &lhs.name, lhs.i, lhs.j);
if (!USELONGJUMP && er) return;
/* the length of the lefthandside string */
if (lhs.i2 == 0) {
maxlen = s.strdim - lhs.i + 1;
} else {
maxlen = lhs.i2 - lhs.i + 1;
if (maxlen > s.strdim) maxlen = s.strdim - lhs.i + 1;
}
/* the number of bytes we want to read the form parameter in WIRE can be used
to set the expected number of bytes */
if (form != 0 && form < maxlen) maxlen = form;
/* what is going on */
if (DEBUG) {
outsc("** input stringcode at "); outnumber(here); outcr();
outsc("** input stringcode "); outname(&lhs.name); outcr();
outsc("** input stringcode maximum length "); outnumber(maxlen); outcr();
}
/* now read the string inplace */
if (prompt) showprompt();
#ifndef USEMEMINTERFACE
newlength = ins(s.ir - 1, maxlen);
#else
newlength = ins(spistrbuf1, maxlen);
/* if we have a string variable, we need to copy the buffer to the string */
if (newlength > 0) {
if (s.ir) {
for (k = 0; k < newlength; k++) s.ir[k] = spistrbuf1[k + 1];
} else {
for (k = 0; k < newlength; k++) memwrite2(s.address + k, spistrbuf1[k + 1]);
}
}
#endif
/* if we have a string variable, we need to copy the buffer to the string */
/* set the right string length */
/* classical Apple 1 behaviour is string truncation in substring logic */
newlength = lhs.i + newlength - 1;
setstringlength(&lhs.name, newlength, lhs.j);
break;
#endif
}
}
/* seperators and termsymbols */
if (token == ',' || token == ';') {
nexttoken();
goto nextstring;
}
/* no further data */
if (!termsymbol()) {
error(EUNKNOWN);
}
resetinput:
id = oldid;
form = 0;
}
/*
GOTO, GOSUB, RETURN and their helpers
GOTO and GOSUB function for a simple one statement goto
*/
void xgoto() {
token_t t = token;
number_t x;
if (!expectexpr()) return;
if (t == TGOSUB) pushgosubstack(0);
if (!USELONGJUMP && er) return;
x = pop();
if (DEBUG) {
outsc("** goto/gosub evaluated line number ");
outnumber(x);
outcr();
}
findline((address_t) x);
if (!USELONGJUMP && er) return;
if (DEBUG) {
outsc("** goto/gosub branches to ");
outnumber(here);
outcr();
}
/* goto in interactive mode switched to RUN mode
no clearing of variables and stacks */
if (st == SINT) st = SRUN;
}
/*
RETURN retrieves here from the gosub stack
*/
void xreturn() {
popgosubstack();
if (DEBUG) {
outsc("** restored location ");
outnumber(here);
outcr();
}
if (!USELONGJUMP && er) return;
nexttoken();
#ifdef HASEVENTS
/* we return from an interrupt and reenable them */
if (gosubarg[gosubsp] == TEVENT) events_enabled = 1;
#endif
}
/*
IF statement together with THEN
*/
void xif() {
mem_t nl = 0;
if (!expectexpr()) return;
x = pop();
if (DEBUG) {
outsc("** in if, condition ");
outnumber(x);
outcr();
}
/* if can have a new line after the expression in this BASIC */
if (token == LINENUMBER) nexttoken();
/* we only check false which is 0 */
if (x == 0) {
#ifndef HASSTRUCT
/* on condition false skip the entire line and all : until a potential ELSE */
while (token != LINENUMBER && token != EOL && token != TELSE) nexttoken();
#else
/* in the structured language set, we need to look for a DO close to the IF and skip it*/
/* a THEN or not and then a line number expects a block */
if (token == TTHEN) nexttoken();
if (token == LINENUMBER) {
nexttoken();
nl = 1;
}
/* skip the block */
if (token == TDO) {
nexttoken();
findbraket(TDO, TDEND);
nexttoken();
goto processelse;
}
/* skip the line */
if (!nl) while (token != LINENUMBER && token != EOL && token != TELSE) nexttoken();
processelse:
#endif
/* if we have ELSE at this point we want to execute this part of the line as the condition
was false, isolated ELSE is GOTO, otherwise just execute the code */
#ifdef HASSTEFANSEXT
/* look if ELSE is at the next line */
if (token == LINENUMBER) nexttoken();
/* now process ELSE */
if (token == TELSE) {
nexttoken();
if (token == NUMBER) {
findline((address_t) x);
return;
}
}
#endif
}
/* a THEN is interpreted as simple one statement goto if it is followed by a line number*/
#ifdef HASAPPLE1
/* then can be on a new line */
if (token == TTHEN) {
nexttoken();
if (token == NUMBER) {
findline((address_t) x);
}
}
#endif
}
/* if else is encountered in the statement line, the rest of the code is skipped
as else code execution is triggered in the xif function */
#ifdef HASSTEFANSEXT
void xelse() {
mem_t nl = 0;
#ifndef HASSTRUCT
/* skip the entire line */
while (token != LINENUMBER && token != EOL) nexttoken();
#else
nexttoken();
/* else in a single line */
if (token == LINENUMBER) {
nexttoken();
nl = 1;
}
/* the block after the else on a new line or the current line */
if (token == TDO) {
nexttoken();
findbraket(TDO, TDEND);
}
/* single line else, skip the line */
if (!nl) while (token != LINENUMBER && token != EOL) nexttoken();
#endif
}
#endif
/*
FOR, NEXT and the apocryphal BREAK
find the NEXT token or the end of the program
*/
/*
The generic block scanner, used for structured code and in FOR NEXT.
The closing symbol of a symbol is found. Symbol pairs are:
FOR NEXT
WHILE WEND
REPEAT UNTIL
DO DEND
SWITCH SWEND
*/
void findbraket(token_t bra, token_t ket) {
address_t fnc = 0;
while (1) {
if (DEBUG) {
outsc("** skpping braket ");
outputtoken(); outspc();
outnumber(here); outspc();
outnumber(fnc); outcr();
}
if (token == ket) {
if (fnc == 0) return; else fnc--;
}
if (token == bra) fnc++;
/* no closing symbol found */
if (token == EOL) {
error(bra);
return;
}
nexttoken();
}
}
/*
FOR variable [= expression [to expression]] [STEP expression]
for stores the variable, the increment and the boudary on the
for stack. Changing steps and boundaries during the execution
of a loop has no effect.
This is different from many other BASICS as FOR can be used
as an open loop with no boundary
*/
void xfor() {
name_t variable;
number_t begin = 1;
number_t to = maxnum;
number_t step = 1;
/* we need at least a name */
if (!expect(VARIABLE, EUNKNOWN)) return;
copyname(&variable, &name);
/*
This is not standard BASIC.
All combinations of FOR TO STEP are allowed.
FOR X : NEXT is an infinite loop.
FOR X=1 : NEXT is a loop with X=1 and an infinite loop.
FOR X=1 TO 10 : NEXT is a loop with X=1 to 10.
FOR X=1 TO 10 STEP 2 : NEXT is a loop with X=1 to 10 in steps of 2.
A variable must always be supplyed to indentify the loop.
FOR : NEXT is illegal.
*/
nexttoken();
if (token == '=') {
if (!expectexpr()) return;
begin = pop();
setvar(&variable, begin);
}
if (token == TTO) {
if (!expectexpr()) return;
to = pop();
}
if (token == TSTEP) {
if (!expectexpr()) return;
step = pop();
}
if (!termsymbol()) {
error(EUNKNOWN);
return;
}
/* in interactive mode we reuse here to store the offset in the buffer */
if (st == SINT) here = bi - ibuffer;
/* here we know everything to set up the loop */
if (DEBUG) {
outsc("** for loop with parameters var begin end step: ");
outname(&variable);
outspc(); outnumber(begin);
outspc(); outnumber(to);
outspc(); outnumber(step);
outcr();
outsc("** for loop target location "); outnumber(here); outcr();
}
pushloop(&variable, TFOR, here, to, step);
if (!USELONGJUMP && er) return;
/*
This tests the condition and stops if it is fulfilled already from start.
There is another apocryphal feature here: STEP 0 is legal triggers an infinite loop.
*/
if ((step > 0 && getvar(&variable) > to) || (step < 0 && getvar(&variable) < to)) {
droploop();
findbraket(TFOR, TNEXT);
nexttoken();
if (token == VARIABLE) nexttoken(); /* This BASIC does not check. */
}
}
/*
BREAK - an apocryphal feature here is the BREAK command ending a loop
*/
#ifdef HASSTRUCT
void xbreak() {
bloop_t* loop;
loop = activeloop();
if (!USELONGJUMP && er) return;
switch (loop->var.token) {
case TWHILE:
findbraket(TWHILE, TWEND);
nexttoken();
break;
case TREPEAT:
findbraket(TREPEAT, TUNTIL);
while (!termsymbol()) nexttoken();
break;
default: /* a FOR loop is the default */
findbraket(TFOR, TNEXT);
nexttoken();
if (token == VARIABLE) nexttoken(); /* we are at next and skip the variable check */
break;
}
droploop();
}
#else
void xbreak() {
droploop();
if (!USELONGJUMP && er) return;
findbraket(TFOR, TNEXT);
nexttoken();
if (token == VARIABLE) nexttoken(); /* we are at next and skip the variable check */
}
#endif
/*
CONT as a loop control statement, as apocryphal as BREAK, simply
advance to next and the continue to process
*/
#ifdef HASSTRUCT
void xcont() {
bloop_t* loop;
loop = activeloop();
if (!USELONGJUMP && er) return;
switch (loop->var.token) {
case TWHILE:
findbraket(TWHILE, TWEND);
break;
case TREPEAT:
findbraket(TREPEAT, TUNTIL);
break;
default: /* a FOR loop is the default */
findbraket(TFOR, TNEXT);
break;
}
}
#else
void xcont() {
findbraket(TFOR, TNEXT);
}
#endif
/*
NEXT variable statement.
This code uses the global name variable right now for processing of
the variable in FOR. The variable name in next is stored in a local variable.
*/
/* reimplementation of xnext without change of the stack in a running loop */
void xnext() {
name_t variable; /* this is a potential variable argument of next */
number_t value;
bloop_t* loop;
/* check is we have the variable argument */
nexttoken();
/* one variable is accepted as an argument, no list */
if (token == VARIABLE) {
if (DEBUG) {
outsc("** variable argument ");
outname(&name);
outcr();
}
copyname(&variable, &name);
nexttoken();
if (!termsymbol()) {
error(EUNKNOWN);
return;
}
} else {
variable.c[0] = 0;
}
/* see whats going on */
loop = activeloop();
if (!USELONGJUMP && er) return;
/* check if this is really a FOR loop */
#ifdef HASSTRUCT
if (loop->var.token == TWHILE || loop->var.token == TREPEAT) {
error(ELOOP);
return;
}
#endif
/* a variable argument in next clears the for stack
down as BASIC programs can and do jump out to an outer next */
if (variable.c[0] != 0) {
while (!cmpname(&variable, &loop->var)) {
droploop();
if (!USELONGJUMP && er) return;
loop = activeloop();
if (!USELONGJUMP && er) return;
}
}
/* step=0 an infinite loop */
/* this goes through the variable name */
#ifndef HASLOOPOPT
value = getvar(&loop->var) + loop->step;
setvar(&loop->var, value);
#else
/* this goes through the stored address and then tries the name (for looping special variables) */
if (loop->varaddress) {
value = getnumber(loop->varaddress, memread2) + loop->step;
setnumber(loop->varaddress, memwrite2, value);
} else {
value = getvar(&loop->var) + loop->step;
setvar(&loop->var, value);
}
#endif
if (DEBUG) {
outsc("** next loop variable "); outname(&loop->var); outspc();
outsc(" value "); outnumber(value); outcr();
}
/* do we need another iteration, STEP 0 always triggers an infinite loop */
if ((loop->step == 0) || (loop->step > 0 && value <= loop->to) || (loop->step < 0 && value >= loop->to)) {
/* iterate in the loop */
here = loop->here;
/* in interactive mode, jump to the right buffer location */
if (st == SINT) bi = ibuffer + here;
} else {
/* last iteration completed we stay here after the next,
no precaution for SINT needed as bi unchanged */
droploop();
}
nexttoken();
if (DEBUG) {
outsc("** after next found token ");
debugtoken();
}
}
/*
TOKEN output - this is also used in save.
list does a minimal formatting with a simple heuristic.
*/
void outputtoken() {
address_t i;
if (token == EOL) return;
if (token == LINENUMBER) outliteral = 0;
if (token == TREM) outliteral = 1;
if (spaceafterkeyword) {
if (token != '(' &&
token != LINENUMBER &&
token != ':' &&
token != '$') outspc();
spaceafterkeyword = 0;
}
switch (token) {
case NUMBER:
outnumber(x);
break;
case LINENUMBER:
outnumber(ax);
outspc();
break;
case ARRAYVAR:
case STRINGVAR:
case VARIABLE:
if (lastouttoken == NUMBER) outspc();
outname(&name);
if (token == STRINGVAR) outch('$');
break;
case STRING:
outch('"');
#ifdef USEMEMINTERFACE
if (!sr.ir) getstringtobuffer(&sr, spistrbuf1, SPIRAMSBSIZE);
#endif
outs(sr.ir, sr.length);
outch('"');
break;
default:
if ( (token < 32 && token >= BASEKEYWORD) || token < -127) {
if ((token == TTHEN ||
token == TELSE ||
token == TTO ||
token == TSTEP ||
token == TGOTO ||
token == TGOSUB ||
token == TOR ||
token == TAND) && lastouttoken != LINENUMBER) outspc();
else if (lastouttoken == NUMBER || lastouttoken == VARIABLE) {
if (token != GREATEREQUAL &&
token <= LESSEREQUAL
&& token != TSHL &&
token != TSHR
) outspc();
}
for (i = 0; gettokenvalue(i) != 0 && gettokenvalue(i) != token; i++);
outsc(getkeyword(i));
if (token != GREATEREQUAL &&
token != NOTEQUAL &&
token != LESSEREQUAL &&
token != TSHL &&
token != TSHR &&
token != TREM &&
token != TFN) spaceafterkeyword = 1;
break;
}
if (token >= 32) {
outch(token);
if (token == ':' && !outliteral) outspc();
break;
}
outch(token); outspc(); outnumber(token);
}
lastouttoken = token;
}
/*
LIST programs to an output device.
The output is formatted to fit the screen, the heuristic is simple.
*/
void listlines(address_t b, address_t e) {
mem_t oflag = 0;
address_t here2 = here;
/* global variables controlling outputtoken, reset to default */
lastouttoken = 0;
spaceafterkeyword = 0;
/* if there is a programm ... */
if (top != 0) {
here = 0;
gettoken();
while (here < top) {
if (token == LINENUMBER && ax >= b) oflag = 1;
if (token == LINENUMBER && ax > e) oflag = 0;
if (oflag) outputtoken();
gettoken();
if (token == LINENUMBER && oflag) {
outcr();
/* wait after every line on small displays
removed if ( dspactive() && (dsp_rows < 10) ){ if ( inch() == 27 ) break;} */
if (dspactive() && dspwaitonscroll() == 27) break;
}
}
if (here == top && oflag) outputtoken();
if (e == maxaddr || b != e) outcr(); /* supress newlines in "list 50" - a little hack */
}
if (st != SINT) here = here2;
}
void xlist() {
address_t b, e;
/* get the argument */
nexttoken();
parsearguments();
if (!USELONGJUMP && er) return;
/* parse the arguments */
switch (args) {
case 0:
b = 0;
e = maxaddr;
break;
case 1:
b = pop();
e = b;
break;
case 2:
e = pop();
b = pop();
break;
default:
error(EARGS);
return;
}
/* list the line from b to e in the default output device */
listlines(b, e);
/* we are done */
nexttoken();
}
/*
The progam line editor, first version. The code is
not save for BUFSIZE greater than 127. A cast to
unsigned char aka uint8_t is needed for the string
length as some platforms have a signed char and some
don't.
*/
void xedit() {
mem_t ood = od;
address_t line;
address_t l;
int i, k, j;
char ch;
/* we edit only in interactive mode */
if (st != SINT) {
error(EUNKNOWN);
return;
}
/* currently only one line number */
if (!expectexpr()) {
error(EARGS);
return;
}
/* this uses the input buffer now */
line = pop();
undo: /* this is the undo point */
ibuffer[0] = 0;
ibuffer[1] = 0;
od = 0;
listlines(line, line);
if (ibuffer[0] == 0) {
outnumber(line);
outspc();
}
od = ood;
/* set the cursor to the first character */
l = 1;
/* editing loop for blocking and non blocking terminals */
while (-1) {
/* show the line and indicate the cursor */
for (i = 1; i <= (unsigned char)ibuffer[0]; i++) outch(ibuffer[i]);
outcr();
for (i = 0; i < l - 1; i++) outspc();
outch('^');
outcr();
/* get a bunch of editing commands and process them*/
i = ins(sbuffer, SBUFSIZE);
for (k = 1; k <= i; k++) {
ch = sbuffer[k];
switch (ch) {
case 'q': /* quit the editor*/
goto done;
case 'Q': /* end the editor without saving */
goto endnosave;
break;
case 'X': /* delete from cursor until the end of the line */
ibuffer[0] = (char)l;
ibuffer[l] = 0;
break;
case 'j': /* vi style left */
if (l > 1) l--;
break;
case 'k': /* vi style right */
if (l < (unsigned char)ibuffer[0]) l++;
break;
case 'x': /* delete the cursor character */
if ((unsigned char)ibuffer[0] > 0) {
for (j = l; j < (unsigned char)ibuffer[0]; j++) ibuffer[j] = ibuffer[j + 1];
ibuffer[j] = 0;
ibuffer[0] = (unsigned char)ibuffer[0] - 1;
}
if ((unsigned char)ibuffer[0] < l) l = (unsigned char)ibuffer[0];
break;
case 's': /* substitute one character at the cursor position */
if (k < i) {
k++;
ibuffer[l] = sbuffer[k];
}
break;
case 'a': /* append multiple characters at the end of the line */
l = (unsigned char)ibuffer[0] + 1;
case 'i': /* insert multiple characters at the cursor position */
if (i - k + (unsigned char)ibuffer[0] < BUFSIZ) {
for (j = i - k + (unsigned char)ibuffer[0]; j >= l; j--) {
ibuffer[j + i - k] = ibuffer[j];
if (j <= l + i - k) ibuffer[j] = sbuffer[k + 1 + (j - l)];
}
}
ibuffer[0] = (unsigned char)ibuffer[0] + i - k;
k = i;
break;
case '^': /* vi style start of line */
l = 1;
break;
case '$': /* vi style end of line */
l = (unsigned char)ibuffer[0] + 1;
break;
case 'h': /* vi style backspace */
if (l > 1) {
for (j = l - 1; j < (unsigned char)ibuffer[0]; j++) ibuffer[j] = ibuffer[j + 1];
ibuffer[j] = 0;
ibuffer[0] = (unsigned char)ibuffer[0] - 1;
l--;
}
break;
case 'u': /* vi style undo */
goto undo;
break;
case ':': /* find the next colon : character*/
if (l <= (unsigned char)ibuffer[0]) {
while (l <= (unsigned char)ibuffer[0] && ibuffer[l] != ':') l++;
if (l <= (unsigned char)ibuffer[0]) l++;
}
break;
default: /* do nothing if the character is not recogized */
break;
}
}
}
/* try to store the line, may heaven help us */
done:
bi = ibuffer;
st = SINT;
nexttoken();
if (token == NUMBER) {
ax = x;
storeline();
}
/* and we are done, restore the output device and clean the buffer */
endnosave:
ibuffer[0] = 0;
ibuffer[1] = 0;
bi = ibuffer + 1;
nexttoken();
}
/*
RUN and CONTINUE are the same function
*/
void xrun() {
if (token == TCONT) {
st = SRUN;
nexttoken();
} else {
nexttoken();
parsearguments();
if (er != 0 ) return;
if (args > 1) {
error(EARGS);
return;
}
if (args == 0) {
here = 0;
} else {
findline(pop());
}
if (!USELONGJUMP && er) return;
if (st == SINT) st = SRUN;
/* all reset on run */
clrvars();
clrgosubstack();
clrforstack();
clrdata();
clrlinecache();
ert = 0;
ioer = 0;
fncontext = 0;
#ifdef HASEVENTS
resettimer(&every_timer);
resettimer(&after_timer);
events_enabled = 1;
#endif
nexttoken();
}
/* once statement is called it stays into a loop until the token stream
is exhausted. Then we return to interactive mode. */
statement();
st = SINT;
/* flush the EEPROM when changing to interactive mode */
eflush();
/* if called from command line with file arg - exit after run */
#ifdef HASARGS
if (bnointafterrun) restartsystem();
#endif
}
/*
a simple help function for the help command, will be extended to
a more sophisticated help system in the future
*/
void xhelp() {
int i;
nexttoken();
if (token == EOL) {
displaybanner();
outsc(getmessage(MKEYWORDS));
for (i = 0; gettokenvalue(i) != 0; i++) {
outsc(getkeyword(i));
outch(' ');
if (i % 8 == 7) outcr();
}
outcr();
} else {
if (token < 31 && token >= BASEKEYWORD) { /* attention, doesn't work with long tokens */
outputtoken();
outsc(": ");
outcr();
}
nexttoken();
}
}
/*
NEW the general cleanup function - new deletes everything
restbasicstate() is a helper, it keeps the memory intact
this is needed for EEPROM direct memory
*/
void resetbasicstate() {
if (DEBUG) {
outsc("** BASIC state reset \n");
}
/* all stacks are purged */
clearst();
clrgosubstack();
clrforstack();
clrdata();
clrvars();
clrlinecache();
/* error status reset */
reseterror();
/* let here point to the beginning of the program */
here = 0;
/* function context back to zero */
fncontext = 0;
/* interactive mode */
st = SINT;
/* switch off timers and interrupts */
#ifdef HASTIMER
resettimer(&after_timer);
resettimer(&every_timer);
#endif
}
void xnew() {
/* reset the state of the interpreter */
resetbasicstate();
if (DEBUG) {
outsc("** clearing memory ");
outnumber(memsize);
outsc(" bytes \n");
}
/* program memory back to zero and variable heap cleared */
himem = memsize;
zeroblock(0, memsize);
top = 0;
if (DEBUG) outsc("** clearing EEPROM state \n ");
/* on EEPROM systems also clear the stored state and top */
#ifdef EEPROMMEMINTERFACE
eupdate(0, 0);
setaddress(1, beupdate, top);
#endif
}
/*
REM - skip everything
*/
void xrem() {
if (debuglevel == -1) outsc("REM: ");
while (token != LINENUMBER && token != EOL && here <= top)
{
nexttoken();
if (debuglevel == -1) {
if (token != LINENUMBER) outputtoken(); else outcr();
}
}
}
/*
The Apple 1 BASIC additions
CLR, DIM, POKE, TAB
*/
/*
CLR - clearing variable space
*/
void xclr() {
#ifdef HASDARKARTS
name_t variable;
nexttoken();
if (termsymbol()) {
clrvars();
clrgosubstack();
clrforstack();
clrdata();
clrlinecache();
ert = 0;
ioer = 0;
} else {
copyname(&variable, &name);
switch (variable.token) {
case VARIABLE:
if (variable.c[0] == '@') {
return;
}
break;
case ARRAYVAR:
nexttoken();
if (token != '(') {
error(EVARIABLE);
return;
}
nexttoken();
if (token != ')') {
error(EVARIABLE);
return;
}
break;
case STRINGVAR:
if (variable.c[0] == '@') {
error(EVARIABLE);
return;
}
break;
case TGOSUB:
clrgosubstack();
goto next;
case TFOR:
clrforstack();
goto next;
case TEVERY:
resettimer(&every_timer);
goto next;
case TAFTER:
resettimer(&after_timer);
goto next;
default:
expression();
if (!USELONGJUMP && er) return;
ax = pop();
variable.c[0] = ax % 256;
variable.c[1] = ax / 256;
variable.token = TBUFFER;
}
/* we have to clear an object, call free */
ax = bfree(&variable);
if (ax == 0) {
if (variable.token != TBUFFER) {
error(EVARIABLE);
return;
}
else ert = 1;
}
}
#else
clrvars();
clrgosubstack();
clrforstack();
clrdata();
clrlinecache();
ert = 0;
ioer = 0;
#endif
next:
nexttoken();
}
#ifdef HASAPPLE1
/*
DIM - the dimensioning of arrays and strings from Apple 1 BASIC
*/
void xdim() {
name_t variable;
address_t x;
address_t y = 1;
/* which object should be dimensioned or created */
nexttoken();
nextvariable:
if (token == ARRAYVAR || token == STRINGVAR ) {
/* remember the object, direct assignment of struct for the moment */
copyname(&variable, &name);
if (DEBUG) {
outsc("** in xdim "); outname(&variable); outspc(); outnumber(variable.token);
outspc(); outname(&name); outspc(); outnumber(name.token); outcr();
}
/* parse the arguments */
parsesubscripts();
if (!USELONGJUMP && er) return;
#ifndef HASMULTIDIM
if (args != 1) {
error(EARGS);
return;
}
x = popaddress();
#else
if (args != 1 && args != 2) {
error(EARGS);
return;
}
if (args == 2) y = popaddress();
x = popaddress();
#endif
/* we create at least one element */
if (x < 1 || y < 1) {
error(EORANGE);
return;
}
/* various checks - do we have enough space in buffers and string indices */
if (variable.token == STRINGVAR) {
if ((x > 255) && (strindexsize == 1)) {
error(EORANGE);
return;
}
#ifdef SPIRAMSBSIZE
if (x > SPIRAMSBSIZE - 1) {
error(EORANGE);
return;
}
#endif
/* With the substringmode switched off, if only one argument is given
we interpret the argument as the string array dimension and not as
the length two arguments are allowed and work as always. This makes
things more compatible to the Microsoft BASIC world. */
if (!substringmode)
if (args == 1) {
y = x;
x = defaultstrdim;
}
(void) createstring(&variable, x, y);
} else {
(void) createarray(&variable, x, y);
}
if (!USELONGJUMP && er) return;
} else if (token == VARIABLE) {
(void) bmalloc(&name, 0); /* this is a local variable, currently no safety net */
} else {
error(EUNKNOWN);
return;
}
nexttoken();
if (token == ',') {
nexttoken();
goto nextvariable;
}
nexttoken();
}
/*
POKE - low level poke to the basic memory.
on 16bit systems, the address is signed, so we can only go up to 32767.
If the address is negative, we poke into the EEPROM.
*/
void xpoke() {
number_t a, v;
/* get the address and the value */
nexttoken();
parsenarguments(2);
if (!USELONGJUMP && er) return;
v = pop(); /* the value */
a = pop(); /* the address */
/* catch memsize here because memwrite doesn't do it */
if (a >= 0 && a <= memsize)
memwrite2(a, v);
else if (a < 0 && a >= -elength())
eupdate(-a - 1, v);
else {
error(EORANGE);
}
}
/*
TAB - spaces command of Apple 1 BASIC
charcount mechanism for relative tab if HASMSTAB is set
*/
void xtab() {
address_t a;
number_t tmp;
token_t t = token;
/* get the number of spaces, we allow brackets here to use xtab also in PRINT */
nexttoken();
if (token == '(') nexttoken();
parsenarguments(1);
if (!USELONGJUMP && er) return;
if (token == ')') nexttoken();
/* we handle negative values here */
tmp = pop();
if (!USELONGJUMP && er) return;
/* negative tabs mapped to 0 */
if (tmp < 0) t = 0;
a = tmp;
/* the runtime environment can do a true tab then ... */
#ifdef HASMSTAB
if (t != TSPC && reltab && od <= OPRT && od >= 0) {
if (charcount[od] >= a) a = 0; else a = a - charcount[od] - 1;
}
#endif
/* debug output */
if (DEBUG) {
outsc("** tabbing ");
outnumber(a);
outsc(" spaces ");
outsc(" charcount");
outnumber(charcount[od - 1]);
outcr();
}
/* output the spaces */
while (a-- > 0) outspc();
}
#endif
/*
locate the curor on the screen
*/
void xlocate() {
address_t cx, cy;
nexttoken();
parsenarguments(2);
if (!USELONGJUMP && er) return;
cy = popaddress();
cx = popaddress();
if (!USELONGJUMP && er) return;
/* for locate we go through the VT52 interface for cursor positioning*/
if (cx > 0 && cy > 0 && cx < 224 && cy < 224) {
outch(27); outch('Y');
outch(31 + (unsigned int) cy);
outch(31 + (unsigned int) cx);
}
/* set the charcount, this is half broken on escape sequences */
#ifdef HASMSTAB
if (od >= 0 && od <= OPRT) charcount[od] = cx;
#endif
}
/*
Stefan's additions to Palo Alto BASIC
DUMP, SAVE, LOAD, GET, PUT, SET
*/
/*
DUMP - memory dump program
*/
void xdump() {
address_t a, x;
char eflag = 0;
nexttoken();
if (token == '!') {
eflag = 1;
nexttoken();
}
parsearguments();
if (!USELONGJUMP && er) return;
switch (args) {
case 0:
x = 0;
a = memsize;
break;
case 1:
x = pop();
a = memsize;
break;
case 2:
a = pop();
x = pop();
break;
default:
error(EARGS);
return;
}
form = 6;
if (a > x) dumpmem((a - x) / 8 + 1, x, eflag);
form = 0;
}
/*
helper of DUMP, wrote the memory out
*/
void dumpmem(address_t r, address_t b, char eflag) {
address_t j, i;
address_t k;
mem_t c;
address_t end;
k = b;
i = r;
if (eflag) end = elength(); else end = memsize;
while (i > 0) {
outnumber(k); outspc();
for (j = 0; j < 8; j++) {
if (eflag) c = eread(k); else c = memread(k);
k++;
outnumber(c); outspc();
if (k > end) break;
}
outcr();
i--;
if (k > end) break;
}
if (eflag) {
outsc("elength: "); outnumber(elength()); outcr();
} else {
outsc("top: "); outnumber(top); outcr();
outsc("himem: "); outnumber(himem); outcr();
}
}
/*
Creates a C string from a BASIC string after reading a BASIC string.
This function handles strings up to SBUFFERSIZE - 1 characters long.
It is used in commands that convert strings like VAL and in handling
filenames.
*/
void stringtobuffer(char *buffer, string_t* s) {
index_t i = s->length;
if (i >= SBUFSIZE) { i = SBUFSIZE - 1; ert=1; }
buffer[i--] = 0;
while (i >= 0) {
buffer[i] = s->ir[i];
i--;
}
}
/* helper for the memintercase code */
void getstringtobuffer(string_t* strp, char *buffer, stringlength_t maxlen) {
stringlength_t i;
for (i = 0; i < strp->length && i < maxlen; i++) buffer[i] = memread2(strp->address + i);
strp->ir = buffer;
}
/* get a file argument */
void getfilename(char *buffer, char d) {
index_t s;
char *sbuffer;
string_t sr;
/* do we have a string argument? */
s = stringvalue(&sr);
if (!USELONGJUMP && er) return;
if (DEBUG) {
outsc("** in getfilename2 stringvalue delivered ");
outnumber(s);
outcr();
}
if (s) {
if (DEBUG) {
outsc("** in getfilename2 copying string of length ");
outnumber(x);
outcr();
}
#ifdef USEMEMINTERFACE
if (!sr.ir) getstringtobuffer(&sr, spistrbuf1, SPIRAMSBSIZE);
#endif
stringtobuffer(buffer, &sr);
if (DEBUG) {
outsc("** in getfilename2 stringvalue string ");
outsc(buffer);
outcr();
}
nexttoken();
} else if (termsymbol()) {
if (d) {
sbuffer = getmessage(MFILE);
s = 0;
while ((sbuffer[s] != 0) && (s < SBUFSIZE - 1)) {
buffer[s] = sbuffer[s];
s++;
}
buffer[s] = 0;
x = s;
} else {
buffer[0] = 0;
x = 0;
}
nexttoken();
} else {
expression();
if (!USELONGJUMP && er) return;
buffer[0] = pop();
buffer[1] = 0;
}
}
/*
an alternative getfilename implementation that simply gives back a buffer
with the filename in it. We avoid a string buffer in the calling commands
like SAVE and LOAD.
*/
char* getfilename2(char d) {
mem_t s;
string_t sr;
/* we have no argument and use the default */
if (termsymbol()) {
if (d) return getmessage(MFILE);
else return 0;
}
/* we have a string argument or an expression */
s = stringvalue(&sr);
if (!USELONGJUMP && er) return 0;
if (s) {
#ifdef USEMEMINTERFACE
if (!sr.ir) getstringtobuffer(&sr, sbuffer, SBUFSIZE);
#endif
nexttoken(); /* undo the rewind of stringvalue, only then use the buffer */
for (s = 0; s < sr.length && s < SBUFSIZE - 1; s++) sbuffer[s] = sr.ir[s];
sbuffer[s] = 0;
return sbuffer;
} else {
expression();
if (!USELONGJUMP && er) return 0;
sbuffer[0] = pop();
sbuffer[1] = 0;
return sbuffer;
}
}
#if defined(FILESYSTEMDRIVER)
/*
SAVE a file either to disk or to EEPROM
*/
void xsave() {
char *filename;
address_t here2;
token_t t;
nexttoken();
filename = getfilename2(1);
if (!USELONGJUMP && er) return;
t = token;
if (filename[0] == '!') {
esave();
} else {
if (DEBUG) {
outsc("** Opening the file ");
outsc(filename);
outcr();
};
if (!ofileopen(filename, "w")) {
error(EFILE);
return;
}
/* save the output mode and then save */
push(od);
od = OFILE;
/* the core save - xlist() not used any more */
ert = 0; /* reset error to trap file problems */
here2 = here;
here = 0;
gettoken();
while (here < top) {
outputtoken();
if (ert) break;
gettoken();
if (token == LINENUMBER) outcr();
}
if (here == top) outputtoken();
outcr();
/* back to where we were */
here = here2;
/* restore the output mode */
od = pop();
/* clean up */
ofileclose();
/* did an accident happen */
if (ert) {
printmessage(EGENERAL);
outcr();
ert = 0;
}
}
/* and continue remembering, where we were */
token = t;
}
/*
LOAD a file, LOAD can either be invoked with a filename argument
or without, in the latter case the filename is read from the token stream
with getfilename.
*/
void xload(const char* f) {
char* filename;
char ch;
address_t here2;
mem_t chain = 0;
if (f == 0) {
nexttoken();
filename = getfilename2(1);
if (!USELONGJUMP && er) return;
} else {
filename = (char*)f;
}
if (filename[0] == '!') {
eload();
} else {
/*
If load is called during runtime it merges
the program as new but perserve the variables
gosub and for stacks are cleared. This is incomplete
as there is one side effect. Functions are not cleared
as they are stored in the heap. If lines are overwritten
by the merge, the function pointers in the heap become
invalid. There is no safety net for this in the current
*/
if (st == SRUN) {
chain = 1;
st = SINT;
top = 0;
clrgosubstack();
clrforstack();
clrdata();
}
if (!f)
if (!ifileopen(filename)) {
error(EFILE);
return;
}
bi = ibuffer + 1;
while (fileavailable()) {
ch = fileread();
if (ch == '\n' || ch == '\r' || cheof(ch)) {
*bi = 0;
bi = ibuffer + 1;
if (*bi != '#') { /* lines starting with a # are skipped - Unix style shell startup */
nexttoken();
if (token == NUMBER) {
ax = x;
storeline();
}
if (er != 0 ) break;
bi = ibuffer + 1;
}
} else {
*bi++ = ch;
}
if ((bi - ibuffer) > BUFSIZE) {
error(EOUTOFMEMORY);
break;
}
}
ifileclose();
/* after a successful load we save top to the EEPROM header */
#ifdef EEPROMMEMINTERFACE
setaddress(1, beupdate, top);
#endif
/* go back to run mode and start from the first line */
if (chain) {
st = SRUN;
here = 0;
nexttoken();
}
}
}
#else
/*
SAVE a file to EEPROM - minimal version for small Arduinos
*/
void xsave() {
esave();
nexttoken();
}
/*
LOAD a file from EEPROM - minimal version for small Arduinos
*/
void xload(const char* f) {
eload();
nexttoken();
}
#endif
/*
GET just one character from input
*/
void xget() {
/* identifier of the lefthandside */
lhsobject_t lhs;
mem_t oid = id; /* remember the input stream */
char ch;
nexttoken();
/* modifiers of the get statement */
if (token == '&') {
if (!expectexpr()) return;
id = pop();
if (token != ',') {
error(EUNKNOWN);
return;
}
nexttoken();
}
/* this code evaluates the left hand side - remember type and name */
copyname(&lhs.name, &name);
lefthandside(&lhs);
if (!USELONGJUMP && er) return;
/* get the data, non blocking on Arduino */
if (availch()) ch = inch(); else ch = 0;
/* store the data element as a number expect for */
assignnumber2(&lhs, ch);
/* but then, strings where we deliver a string with length 0 if there is no data */
#ifdef HASAPPLE1
if (lhs.name.token == STRINGVAR && ch == 0 && lhs.ps) setstringlength(&lhs.name, 0, arraylimit);
#endif
/* restore the output device */
id = oid;
}
/*
PUT writes one character to an output stream
*/
void xput() {
mem_t ood = od;
index_t i;
nexttoken();
/* modifiers of the put statement */
if (token == '&') {
if (!expectexpr()) return;
od = pop();
if (token != ',') {
error(EUNKNOWN);
return;
}
nexttoken();
}
parsearguments();
if (!USELONGJUMP && er) return;
for (i = args - 1; i >= 0; i--) sbuffer[i] = pop();
outs(sbuffer, args);
od = ood;
}
/* setpersonality is a helper of xset */
void setpersonality(index_t p) {
#ifdef HASAPPLE1
switch (p) {
/* a Microsoft like BASIC have arrays starting at 0 with n+1 elements and no substrings, MS type RND */
case 'm':
case 'M':
msarraylimits = 1;
arraylimit = 0;
substringmode = 0;
booleanmode = -1;
randombase = -1;
reltab = 1;
break;
/* an Apple 1 like BASIC have arrays starting at 1 with n elements and substrings */
case 'a':
case 'A':
msarraylimits = 0;
arraylimit = 1;
substringmode = 1;
booleanmode = 1;
randombase = 0;
reltab = 0;
break;
/* PaloAlto BASIC is an integer basic with slightly different behaviour */
case 'p':
case 'P':
msarraylimits = 0;
arraylimit = 0;
substringmode = 1;
booleanmode = 1;
forceint = 1;
randombase = 1;
reltab = 0;
break;
}
#endif
}
/*
SET - the command itself is also apocryphal it is a low level
control command setting certain properties
syntax, currently it is only SET expression, expression
*/
void xset() {
address_t function;
index_t argument;
nexttoken();
parsenarguments(2);
if (!USELONGJUMP && er) return;
argument = pop();
function = pop();
switch (function) {
/* runtime debug level */
case 0:
debuglevel = argument;
break;
/* autorun/run flag of the EEPROM 255 for clear, 0 for prog, 1 for autorun */
/* eflush() is needed to make sure the change is written immediately */
/* the bdelay is only for protection of the eeprom against tight loops doing SET 1,x */
case 1:
eupdate(0, argument);
eflush();
bdelay(1000);
break;
/* change the output device */
case 2:
switch (argument) {
case 0:
od = OSERIAL;
break;
case 1:
od = ODSP;
break;
}
break;
/* change the default output device */
case 3:
switch (argument) {
case 0:
od = (odd = OSERIAL);
break;
case 1:
od = (odd = ODSP);
break;
}
break;
/* change the input device */
case 4:
switch (argument) {
case 0:
id = ISERIAL;
break;
case 1:
id = IKEYBOARD;
break;
}
break;
/* change the default input device */
case 5:
switch (argument) {
case 0:
idd = (id = ISERIAL);
break;
case 1:
idd = (id = IKEYBOARD);
break;
}
break;
#ifdef HASSERIAL1
/* set the cr behaviour */
case 6:
sendcr = (char)argument;
break;
/* set the blockmode behaviour */
case 7:
blockmode = argument;
break;
/* set the second serial ports baudrate */
case 8:
prtset(argument);
break;
#endif
/* set the power amplifier level of the radio module */
#ifdef HASRF24
case 9:
radioset(argument);
break;
#endif
/* display update control for paged displays */
#ifdef DISPLAYDRIVER
case 10:
dspsetupdatemode(argument);
break;
#endif
/* change the output device to a true TAB */
#ifdef HASMSTAB
case 11:
reltab = argument;
break;
#endif
/* change the lower array limit */
#ifdef HASAPPLE1
case 12:
if (argument >= 0) arraylimit = argument; else error(EORANGE);
break;
#endif
/* the keyboard repeat frequency */
#ifdef HASKEYPAD
case 13:
kbdrepeat = argument;
break;
#endif
/* the units the pulse command is using */
#ifdef HASPULSE
case 14:
bpulseunit = argument;
break;
#endif
/* switch on the vt52 emulation an a POSIX system with an ANSI terminal */
#ifdef POSIXVT52TOANSI
case 15:
vt52active = argument;
break;
#endif
/* change the default size of a string at autocreate */
#ifdef HASAPPLE1
case 16:
if (argument > 0) defaultstrdim = argument; else error(EORANGE);
break;
#endif
/* set the boolean mode */
case 17:
if (argument == -1 || argument == 1) booleanmode = argument; else error(EORANGE);
break;
/* set the integer mode */
case 18:
forceint = (argument != 0);
break;
/* set the random number behaviour */
case 19:
randombase = argument;
break;
/* the substring mode on and off */
#ifdef HASAPPLE1
case 20:
substringmode = (argument != 0);
break;
#endif
/* the MS array behaviour, creates n+1 elements when on */
#ifdef HASAPPLE1
case 21:
msarraylimits = (argument != 0);
break;
#endif
/* set many settings at once to change the entire personality of the interpreter */
case 22:
setpersonality(argument);
break;
#ifdef HASAPPLE1
case 23:
lowercasenames = (argument != 0);
break;
#endif
#ifdef HASFLOAT
case 24:
precision = argument;
break;
#endif
}
}
/*
NETSTAT - network status command, rudimentary
*/
void xnetstat() {
#if defined(HASMQTT)
nexttoken();
parsearguments();
if (!USELONGJUMP && er) return;
switch (args) {
case 0:
if (netconnected()) outsc("Network connected \n"); else outsc("Network not connected \n");
outsc("MQTT state "); outnumber(mqttstate()); outcr();
outsc("MQTT out topic "); outsc(mqtt_otopic); outcr();
outsc("MQTT inp topic "); outsc(mqtt_itopic); outcr();
outsc("MQTT name "); outsc(mqttname); outcr();
break;
case 1:
ax = pop();
switch (ax) {
case 0:
netstop();
break;
case 1:
netbegin();
break;
case 2:
if (!mqttreconnect()) ert = 1;
break;
default:
error(EARGS);
return;
}
break;
default:
error(EARGS);
return;
}
#endif
nexttoken();
}
/*
The arduino io functions.
*/
/*
rtaread and rtdread are wrappers coming from runtime
This is done for portability for raspberry pi and other systems
*/
void xaread() {
push(aread(popaddress()));
}
void xdread() {
push(dread(popaddress()));
}
/*
DWRITE - digital write
*/
void xdwrite() {
address_t x, y;
nexttoken();
parsenarguments(2);
if (!USELONGJUMP && er) return;
x = popaddress();
y = popaddress();
if (!USELONGJUMP && er) return;
dwrite(y, x);
}
/*
AWRITE - analog write
*/
void xawrite() {
address_t x, y;
nexttoken();
parsenarguments(2);
if (!USELONGJUMP && er) return;
x = popaddress();
if (x > 255) error(EORANGE);
y = popaddress();
if (!USELONGJUMP && er) return;
awrite(y, x);
}
/*
PINM - pin mode
*/
void xpinm() {
address_t x, y;
nexttoken();
parsenarguments(2);
if (!USELONGJUMP && er) return;
x = popaddress();
if (x > 1) error(EORANGE);
y = popaddress();
if (!USELONGJUMP && er) return;
pinm(y, x);
}
/*
DELAY in milliseconds
this must call bdelay() and not delay() as bdelay()
handles all the yielding and timing functions
*/
void xdelay() {
nexttoken();
parsenarguments(1);
if (!USELONGJUMP && er) return;
bdelay(pop());
}
/* tone if the platform has it -> BASIC command PLAY */
#ifdef HASTONE
/* play a tone */
void xtone() {
address_t d = 0;
address_t v = 100;
address_t f, p;
/* get minimum of 2 and maximum of 4 args */
nexttoken();
parsearguments();
if (!USELONGJUMP && er) return;
if (args > 4 || args < 2) {
error(EARGS);
return;
}
/* a switch would be more elegant but needs more progspace ;-) */
if (args == 4) v = popaddress();
if (args >= 3) d = popaddress();
f = popaddress();
p = popaddress();
if (!USELONGJUMP && er) return;
playtone(p, f, d, v);
}
#endif
/* pulse output - pin, duration, [value], [repetitions, delay] */
#ifdef HASPULSE
void xpulse() {
address_t pin, duration;
address_t val = 1;
address_t interval = 0;
address_t repetition = 1;
/* do we have at least 2 and not more than 5 arguments */
nexttoken();
parsearguments();
if (!USELONGJUMP && er) return;
if (args > 5 || args < 2) {
error(EARGS);
return;
}
/* get the data from stack */
if (args == 5) {
interval = popaddress();
repetition = popaddress();
}
if (args == 4) {
error(EARGS);
return;
}
if (args > 2) val = popaddress();
duration = popaddress();
pin = popaddress();
if (!USELONGJUMP && er) return;
/* low level run time function for the pulse */
pulseout(bpulseunit, pin, duration, val, repetition, interval);
}
/* read a pulse, units given by bpulseunit - default 10 microseconds */
void bpulsein() {
address_t x, y;
unsigned long t, pt;
t = ((unsigned long) popaddress()) * 1000;
y = popaddress();
x = popaddress();
if (!USELONGJUMP && er) return;
push(pulsein(x, y, t) / bpulseunit);
}
#endif
#ifdef HASGRAPH
/*
COLOR setting, accepting one or 3 arguments
*/
void xcolor() {
int r, g, b;
nexttoken();
parsearguments();
if (!USELONGJUMP && er) return;
switch (args) {
case 1:
vgacolor(pop());
break;
case 3:
b = pop();
g = pop();
r = pop();
rgbcolor(r, g, b);
break;
default:
error(EARGS);
break;
}
}
/*
PLOT a pixel on the screen
*/
void xplot() {
int x0, y0;
nexttoken();
parsenarguments(2);
if (!USELONGJUMP && er) return;
y0 = pop();
x0 = pop();
plot(x0, y0);
}
/*
LINE draws a line
*/
void xline() {
int x0, y0, x1, y1;
nexttoken();
parsenarguments(4);
if (!USELONGJUMP && er) return;
y1 = pop();
x1 = pop();
y0 = pop();
x0 = pop();
line(x0, y0, x1, y1);
}
void xrect() {
int x0, y0, x1, y1;
nexttoken();
parsenarguments(4);
if (!USELONGJUMP && er) return;
y1 = pop();
x1 = pop();
y0 = pop();
x0 = pop();
rect(x0, y0, x1, y1);
}
void xcircle() {
int x0, y0, r;
nexttoken();
parsenarguments(3);
if (!USELONGJUMP && er) return;
r = pop();
y0 = pop();
x0 = pop();
circle(x0, y0, r);
}
void xfrect() {
int x0, y0, x1, y1;
nexttoken();
parsenarguments(4);
if (!USELONGJUMP && er) return;
y1 = pop();
x1 = pop();
y0 = pop();
x0 = pop();
frect(x0, y0, x1, y1);
}
void xfcircle() {
int x0, y0, r;
nexttoken();
parsenarguments(3);
if (!USELONGJUMP && er) return;
r = pop();
y0 = pop();
x0 = pop();
fcircle(x0, y0, r);
}
#endif
#ifdef HASDARKARTS
/*
MALLOC allocates a chunk of memory
*/
void xmalloc() {
address_t s;
address_t a;
name_t name;
/* size and identifier */
s = popaddress();
a = popaddress();
if (!USELONGJUMP && er) return;
/* create a name */
name.token = TBUFFER;
name.l = 2;
name.c[0] = a % 256;
name.c[1] = a / 256;
/* allocate the memory */
push(bmalloc(&name, s));
}
/*
FIND an object on the heap
xfind can find things in the variable name space and the buffer space
*/
void xfind() {
address_t a;
address_t n;
/* is there a ( */
if (!expect('(', EUNKNOWN)) return;
/* after that, try to find the object on the heap */
nexttoken();
if (token == TFN) {
nexttoken();
name.token = TFN;
}
a = bfind(&name);
/* depending on the object, interpret the result */
switch (token) {
case ARRAYVAR:
case TFN:
if (!expect('(', EUNKNOWN)) return;
if (!expect(')', EUNKNOWN)) return;
case VARIABLE:
case STRINGVAR:
nexttoken();
break;
default:
expression(); /* do not use expectexpr here because of the token sequence */
if (!USELONGJUMP && er) return;
n = popaddress();
if (!USELONGJUMP && er) return;
name.token = TBUFFER;
name.l = 2;
name.c[0] = n % 256;
name.c[1] = n / 256;
a = bfind(&name);
}
/* closing braket, dont use expect here because of the token sequence */
if (token != ')') {
error(EUNKNOWN);
return;
}
push(a);
}
/*
EVAL can modify a program, there are serious side effects
which are not caught (and cannot be). All FOR loops and RETURN
vectors break if EVAL inserts in their range
*/
void xeval() {
address_t i, l;
address_t mline, line;
string_t s;
/* get the line number to store */
if (!expectexpr()) return;
line = popaddress();
if (!USELONGJUMP && er) return;
if (token != ',') {
error(EUNKNOWN);
return;
}
/* the line to be stored */
nexttoken();
if (!stringvalue(&s)) {
error(EARGS);
return;
}
/* here we have the string to evaluate it to the ibuffer
only one line allowed, BUFSIZE is the limit */
l = s.length;
if (!USELONGJUMP && er) return;
if (l > BUFSIZE - 1) {
error(EORANGE);
return;
}
#ifdef USEMEMINTERFACE
if (!s.ir) getstringtobuffer(&s, spistrbuf1, SPIRAMSBSIZE);
#endif
for (i = 0; i < l; i++) ibuffer[i + 1] = s.ir[i];
ibuffer[l + 1] = 0;
if (DEBUG) {
outsc("** Preparing to store line ");
outnumber(line);
outspc();
outsc(ibuffer + 1);
outcr();
}
/* we find the line we are currently at */
if (st != SINT) {
mline = myline(here);
if (DEBUG) {
outsc("** myline is ");
outnumber(mline);
outcr();
}
}
/* go to interactive mode and try to store the line */
ax = line; // the linennumber
push(st); st = SINT; // go to (fake) interactive mode
bi = ibuffer; // go to the beginning of the line
storeline(); // try to store it
st = pop(); // go back to run mode
/* find my line - side effects not checked here */
if (st != SINT) {
findline(mline);
nextline();
}
}
#endif
#ifdef HASIOT
/*
AVAIL of a stream - are there characters in the stream
*/
void xavail() {
mem_t oid = id;
id = popaddress();
if (!USELONGJUMP && er) return;
push(availch());
id = oid;
}
/*
IoT functions - sensor reader, experimentral
*/
void xfsensor() {
address_t s, a;
a = popaddress();
if (!USELONGJUMP && er) return;
s = popaddress();
if (!USELONGJUMP && er) return;
push(sensorread(s, a));
}
/*
Going to sleep for battery saving - implemented for ESP8266 and ESP32
in hardware-*.h
*/
void xsleep() {
nexttoken();
parsenarguments(1);
if (!USELONGJUMP && er) return;
activatesleep(pop());
}
/*
single byte wire access - keep it simple
*/
void xwire() {
int i;
nexttoken();
#if defined(HASWIRE) || defined(HASSIMPLEWIRE)
/* a stop causes a release of the bus, can be used after multiple one byte writes
currently part of the cycle */
/*
if (token == STOP) {
wirestop();
return;
}
*/
parsearguments();
if (!USELONGJUMP && er) return;
/* this code is the only place where the stack is accessed directly */
if (args > 1) {
wirestart((int)stack[sp-args].n, 0);
for(i=1; i<args; i++) wirewritebyte((int)stack[sp-args+i].n);
wirestop();
sp-=args;
} else {
error(EARGS);
return;
}
#endif
}
void xfwire() {
#if defined(HASWIRE) || defined(HASSIMPLEWIRE)
int port;
ioer=0;
port=pop();
if (!USELONGJUMP && er) return;
wirestart(port, 1);
push(wirereadbyte());
#endif
}
#endif
/*
Error handling function.
*/
#ifdef HASERRORHANDLING
void xerror() {
berrorh.type = 0;
erh = 0;
nexttoken();
switch (token) {
case TGOTO:
if (!expectexpr()) return;
berrorh.type = TGOTO;
berrorh.linenumber = pop();
break;
case TCONT:
berrorh.type = TCONT;
case TSTOP:
nexttoken();
break;
default:
error(EARGS);
return;
}
}
#endif
/*
After and every trigger timing GOSUBS and GOTOS.
*/
#ifdef HASTIMER
void resettimer(btimer_t* t) {
t->enabled = 0;
t->interval = 0;
t->last = 0;
t->type = 0;
t->linenumber = 0;
}
void xtimer() {
token_t t;
btimer_t* timer;
/* do we deal with every or after */
if (token == TEVERY) timer = &every_timer; else timer = &after_timer;
/* one argument expected, the time intervall */
if (!expectexpr()) return;
/* after that, a command GOTO or GOSUB with a line number
more commands thinkable */
switch (token) {
case TGOSUB:
case TGOTO:
t = token;
if (!expectexpr()) return;
timer->last = millis();
timer->type = t;
timer->linenumber = pop();
timer->interval = pop();
timer->enabled = 1;
break;
default:
if (termsymbol()) {
x = pop();
if (x == 0)
timer->enabled = 0;
else {
if (timer->linenumber) {
timer->enabled = 1;
timer->interval = x;
timer->last = millis();
} else
error(EARGS);
}
} else
error(EUNKNOWN);
return;
}
}
#endif
#ifdef HASEVENTS
/*
The events API for Arduino with interrupt service routines
analogous to the timer API.
we use raw modes here
#define CHANGE 1
#define FALLING 2
#define RISING 3
detach und attach are wrappers around the original Arduino functions.
Runtime needs to be compiled with #define ARDUINOINTERRUPTS for this to
work.
*/
/* interrupts in BASIC fire once and then disable themselves, BASIC reenables them */
void bintroutine0() {
eventlist[0].active = 1;
detachinterrupt(eventlist[0].pin);
}
void bintroutine1() {
eventlist[1].active = 1;
detachinterrupt(eventlist[1].pin);
}
void bintroutine2() {
eventlist[2].active = 1;
detachinterrupt(eventlist[2].pin);
}
void bintroutine3() {
eventlist[3].active = 1;
detachinterrupt(eventlist[3].pin);
}
mem_t eventindex(mem_t pin) {
mem_t i;
for (i = 0; i < EVENTLISTSIZE; i++ ) if (eventlist[i].pin == pin) return i;
return -1;
}
mem_t enableevent(mem_t pin) {
mem_t inter;
mem_t i;
/* do we have the data */
if ((i = eventindex(pin)) < 0) return 0;
/* can we use this pin? */
inter = pintointerrupt(eventlist[i].pin);
if (inter < 0) return 0;
/* attach the interrupt function to this pin */
switch (i) {
case 0:
attachinterrupt(inter, bintroutine0, eventlist[i].mode);
break;
case 1:
attachinterrupt(inter, bintroutine1, eventlist[i].mode);
break;
case 2:
attachinterrupt(inter, bintroutine2, eventlist[i].mode);
break;
case 3:
attachinterrupt(inter, bintroutine3, eventlist[i].mode);
break;
default:
return 0;
}
/* now set it enabled in BASIC */
eventlist[i].enabled = 1;
return 1;
}
void disableevent(mem_t pin) {
detachinterrupt(pin);
}
/* the event BASIC commands */
void initevents() {
mem_t i;
for (i = 0; i < EVENTLISTSIZE; i++) eventlist[i].pin = -1;
nevents = 0;
}
void xevent() {
mem_t pin, mode;
mem_t type = 0;
address_t line = 0;
/* in this version two arguments are neded, one is the pin, the second the mode */
nexttoken();
/* debug code, display the event list */
if (termsymbol()) {
for (ax = 0; ax < EVENTLISTSIZE; ax++) {
if (eventlist[ax].pin >= 0) {
outnumber(eventlist[ax].pin); outspc();
outnumber(eventlist[ax].mode); outspc();
// outnumber(eventlist[ax].type); outspc();
if (eventlist[ax].type == TGOTO) outsc("GOTO"); else outsc("GOSUB");
outspc();
outnumber(eventlist[ax].linenumber); outspc();
outcr();
}
}
outnumber(nevents); outcr();
nexttoken();
return;
}
/* control of events */
/* stop and continue */
if (token == TSTOP) {
events_enabled = 0;
nexttoken();
return;
}
if (token == TCONT) {
events_enabled = 1;
nexttoken();
return;
}
/* clear the event list */
if (token == TCLR) {
initevents();
nexttoken();
return;
}
/* argument parsing */
parsearguments();
if (!USELONGJUMP && er) return;
switch (args) {
case 2:
mode = pop();
if (mode > 3) {
error(EARGS);
return;
}
case 1:
pin = pop();
break;
default:
error(EARGS);
}
/* followed by termsymbol, GOTO or GOSUB */
if (token == TGOTO || token == TGOSUB) {
type = token;
/* which line to go to */
if (!expectexpr()) return;
line = pop();
} else {
if (!termsymbol()) {
error(EARGS);
return;
}
}
/* all done either set the interrupt up or delete it*/
if (type) {
if (!addevent(pin, mode, type, line)) {
error(EARGS);
return;
}
} else {
disableevent(pin);
deleteevent(pin);
return;
}
/* enable the interrupt */
if (!enableevent(pin)) {
deleteevent(pin);
error(EARGS);
return;
}
}
/* handling the event list */
mem_t addevent(mem_t pin, mem_t mode, mem_t type, address_t linenumber) {
int i;
/* is the event already there */
for (i = 0; i < EVENTLISTSIZE; i++)
if (pin == eventlist[i].pin) goto slotfound;
/* if not, look for a free slot */
/* there is none, return with an error */
if (nevents >= EVENTLISTSIZE) return 0;
/* we have a free slot, increase number of events in list */
for (i = 0; i < EVENTLISTSIZE; i++)
if (eventlist[i].pin == -1) {
nevents++;
goto slotfound;
}
/* no free event slot */
return 0;
/* we have a slot */
slotfound:
eventlist[i].enabled = 0;
eventlist[i].pin = pin;
eventlist[i].mode = mode;
eventlist[i].type = type;
eventlist[i].linenumber = linenumber;
eventlist[i].active = 0;
return 1;
}
void deleteevent(mem_t pin) {
int i;
/* do we have the event? */
i = eventindex(pin);
if (i >= 0) {
eventlist[i].enabled = 0;
eventlist[i].pin = -1;
eventlist[i].mode = 0;
eventlist[i].type = 0;
eventlist[i].linenumber = 0;
eventlist[i].active = 0;
nevents--;
}
}
#endif
/*
BASIC DOS - disk access programs, to control mass storage from BASIC
*/
/* string match helper in catalog */
char streq(const char *s, char *m) {
short i = 0;
while (m[i] != 0 && s[i] != 0 && i < SBUFSIZE) {
if (s[i] != m[i]) return 0;
i++;
}
return 1;
}
/*
CATALOG - basic directory function
*/
void xcatalog() {
#if defined(FILESYSTEMDRIVER)
char filename[SBUFSIZE];
const char *name;
nexttoken();
getfilename(filename, 0);
if (!USELONGJUMP && er) return;
rootopen();
while (rootnextfile()) {
if (rootisfile()) {
name = rootfilename();
if (*name != '_' && *name != '.' && streq(name, filename)) {
outscf(name, 14); outspc();
if (rootfilesize() > 0) outnumber(rootfilesize());
outcr();
if (dspwaitonscroll() == 27) break;
}
}
rootfileclose();
}
rootclose();
#else
nexttoken();
#endif
}
/*
DELETE a file
*/
void xdelete() {
#if defined(FILESYSTEMDRIVER)
char filename[SBUFSIZE];
nexttoken();
getfilename(filename, 0);
if (!USELONGJUMP && er) return;
removefile(filename);
#else
nexttoken();
#endif
}
/*
OPEN a file or I/O stream - very raw mix of different functions
*/
void xopen() {
#if defined(FILESYSTEMDRIVER) || defined(HASRF24) || defined(HASMQTT) || defined(HASWIRE) || defined(HASSERIAL1)
char stream = IFILE; /* default is file operation */
char* filename;
int mode;
/* which stream do we open? default is FILE */
nexttoken();
if (token == '&') {
if (!expectexpr()) return;
stream = pop();
if (token != ',') {
error(EUNKNOWN);
return;
}
nexttoken();
}
/* the filename and its length */
// getfilename(filename, 0);
filename = getfilename2(0);
if (!USELONGJUMP && er) return;
/* and the arguments */
args = 0;
if (token == ',') {
nexttoken();
parsearguments();
}
/* getting an argument, no argument is read, i.e. mode 0 */
if (args == 0 ) {
mode = 0;
} else if (args == 1) {
mode = pop();
} else {
error(EARGS);
return;
}
/* open the stream */
switch (stream) {
#ifdef HASSERIAL1
case ISERIAL1:
prtclose();
if (mode == 0) mode = 9600;
if (prtopen(filename, mode)) ert = 0; else ert = 1;
break;
#endif
#ifdef FILESYSTEMDRIVER
case IFILE:
switch (mode) {
case 1:
ofileclose();
if (ofileopen(filename, "w")) ert = 0; else ert = 1;
break;
case 2:
ofileclose();
if (ofileopen(filename, "a")) ert = 0; else ert = 1;
break;
default:
case 0:
ifileclose();
if (ifileopen(filename)) ert = 0; else ert = 1;
break;
}
break;
#endif
#ifdef HASRF24
case IRADIO:
if (mode == 0) {
iradioopen(filename);
} else if (mode == 1) {
oradioopen(filename);
}
break;
#endif
#if defined(HASWIRE)
case IWIRE:
wireopen(filename[0], mode);
break;
#endif
#ifdef HASMQTT
case IMQTT:
if (mode == 0) {
mqttsubscribe(filename);
} else if (mode == 1) {
mqttsettopic(filename);
}
break;
#endif
default:
error(EORANGE);
return;
}
#endif
nexttoken();
}
/*
OPEN as a function, currently only implemented for MQTT
*/
void xfopen() {
address_t stream = popaddress();
if (stream == 9) push(mqttstate()); else push(0);
}
/*
CLOSE a file or stream
*/
void xclose() {
#if defined(FILESYSTEMDRIVER) || defined(HASRF24) || defined(HASMQTT) || defined(HASWIRE)
char stream = IFILE;
char mode;
nexttoken();
if (token == '&') {
if (!expectexpr()) return;
stream = pop();
if (token != ',' && ! termsymbol()) {
error(EUNKNOWN);
return;
}
nexttoken();
}
parsearguments();
if (args == 0) {
mode = 0;
} else if (args == 1) {
mode = pop();
} else {
error(EARGS);
return;
}
/* currently only close of files is implemented, should be also implemented for Wire */
switch (stream) {
case IFILE:
if (mode == 1 || mode == 2) ofileclose(); else if (mode == 0) ifileclose();
break;
}
#endif
nexttoken();
}
/*
FDISK - format internal disk storages of RP2040, ESP and the like
*/
void xfdisk() {
#if defined(FILESYSTEMDRIVER)
nexttoken();
parsearguments();
if (!USELONGJUMP && er) return;
if (args > 1) error(EORANGE);
if (args == 0) push(0);
outsc("Format disk (y/N)?");
(void) consins(sbuffer, SBUFSIZE);
if (sbuffer[1] == 'y') formatdisk(pop());
if (fsstat(1) > 0) outsc("ok\n"); else outsc("fail\n");
#endif
nexttoken();
}
#ifdef HASUSRCALL
/*
USR low level function access of the interpreter
for each group of functions there is a call vector
and and argument.
USR arguments from 0 to 31 are reserved for the
interpreter status and the input output stream
mechanisms. All other values are free and can be used
for individual functions - see case 32 for an example.
*/
void xusr() {
address_t fn;
number_t v;
int arg;
address_t a;
v = pop();
arg = (int)v; /* a bit paranoid here */
fn = pop();
switch (fn) {
/* USR(0,y) delivers all the internal constants and variables or the interpreter */
case 0:
switch (arg) {
case 0:
push(bsystype);
break;
case 1: /* language set identifier, odd because USR is part of STEFANSEXT*/
a = 0;
#ifdef HASAPPLE1
a |= 1;
#endif
#ifdef HASARDUINOIO
a |= 2;
#endif
#ifdef HASFILEIO
a |= 4;
#endif
#ifdef HASDARTMOUTH
a |= 8;
#endif
#ifdef HASGRAPH
a |= 16;
#endif
#ifdef HASDARKARTS
a |= 32;
#endif
#ifdef HASIOT
a |= 64;
#endif
push(a); break;
case 2:
push(0); break; /* reserved for system speed identifier */
#ifdef HASFLOAT
case 3: push(-1); break;
#else
case 3: push(0); break;
#endif
case 4: push(numsize); break;
case 5: push(maxnum); break;
case 6: push(addrsize); break;
case 7: push(maxaddr); break;
case 8: push(strindexsize); break;
case 9: push(memsize + 1); break;
case 10: push(elength()); break;
case 11: push(GOSUBDEPTH); break;
case 12: push(FORDEPTH); break;
case 13: push(STACKSIZE); break;
case 14: push(BUFSIZE); break;
case 15: push(SBUFSIZE); break;
case 16: push(ARRAYSIZEDEF); break;
case 17: push(defaultstrdim); break;
// - 24 reserved, don't use
case 24: push(top); break;
case 25: push(here); break;
case 26: push(himem); break;
case 27: push(0); break;
case 28: push(freeRam()); break;
case 29: push(gosubsp); break;
case 30: push(loopsp); break;
case 31: push(0); break; // fnc removed as interpreter variable
case 32: push(sp); break;
#ifdef HASDARTMOUTH
case 33: push(data); break;
#else
case 33: push(0); break;
#endif
case 34: push(0); break;
#ifdef FASTTICKERPROFILE
case 35:
push(avgfastticker());
clearfasttickerprofile();
break;
#endif
/* - 48 reserved, don't use */
case 48: push(id); break;
case 49: push(idd); break;
case 50: push(od); break;
case 51: push(odd); break;
default: push(0);
}
break;
/* access to properties of stream 1 - serial */
case 1:
push(serialstat(arg));
break;
/* access to properties of stream 2 - display and keyboard */
case 2:
#if defined(DISPLAYDRIVER) || defined(GRAPHDISPLAYDRIVER)
push(dspstat(arg));
#elif defined(ARDUINOVGA)
push(vgastat(arg));
#else
push(0);
#endif
break;
/* access to properties of stream 4 - printer */
#ifdef HASSERIAL1
case 4:
push(prtstat(arg));
break;
#endif
/* access to properties of stream 7 - wire */
#if defined(HASWIRE)
case 7:
push(wirestat(arg));
break;
#endif
/* access to properties of stream 8 - radio */
#ifdef HASRF24
case 8:
push(radiostat(arg));
break;
#endif
/* access to properties of stream 9 - mqtt */
#ifdef HASMQTT
case 9:
push(mqttstat(arg));
break;
#endif
/* access to properties of stream 16 - file */
#ifdef FILESYSTEMDRIVER
case 16:
push(fsstat(arg));
break;
#endif
case 32:
/* user function 32 and beyond can be used freely */
/* all USR values not assigned return 0 */
default:
if (fn > 31) push(usrfunction(fn, v)); else push(0);
}
}
/*
CALL currently only to exit the interpreter
*/
void xcall() {
int r;
if (!expectexpr()) return;
r = pop();
switch (r) {
case 0:
/* flush the EEPROM dummy and the output file and then exit */
eflush();
ofileclose();
#if defined(POSIXFRAMEBUFFER)
vgaend(); /* clean up if you have played with the framebuffer */
#endif
restartsystem();
break;
/* restart the filesystem - only test code */
case 1:
fsbegin();
break;
/* show the banner again */
case 2:
displaybanner();
break;
/* hard network start */
case 3:
#ifdef ARDUINOMQTT
netbegin();
mqttbegin();
#endif
break;
/* call values to 31 reserved! */
default:
/* your custom code into usrcall() */
if (r > 31) usrcall(r); else {
error(EORANGE);
return;
}
nexttoken();
return;
}
}
#endif
/* the dartmouth stuff */
#ifdef HASDARTMOUTH
/*
DATA is simply skipped when encountered as a command
*/
void xdata() {
while (!termsymbol()) nexttoken();
}
/*
for READ find the next data record, helper of READ
*/
void nextdatarecord() {
address_t h;
mem_t s = 1;
/* save the location of the interpreter and the token we are processing */
h = here;
/* data at zero means we need to init it, by searching the first data record */
if (data == 0) {
here = 0;
while (here < top && token != TDATA) gettoken();
data = here;
datarc = 1;
}
processdata:
/*
data at top means we have exhausted all data,
nothing more to be done here, however we simulate
a number value of 0 here and don't throw an error
this is not Dartmouth style, more consistent with
iterables
*/
if (data == top) {
token = NUMBER;
x = 0;
ert = 1;
here = h;
return;
}
/* we process the data record by setting the here pointer to data and search with gettoken */
here = data;
gettoken();
if (token == '-') {
s = -1;
gettoken();
}
if (token == NUMBER || token == STRING) goto enddatarecord;
if (token == ',') {
gettoken();
if (token == '-') {
s = -1;
gettoken();
}
if (token != NUMBER && token != STRING) {
error(EUNKNOWN);
here = h;
return;
}
goto enddatarecord;
}
if (termsymbol()) {
while (here < top && token != TDATA) gettoken();
data = here;
goto processdata;
}
if (DEBUG) {
outsc("** error in nextdata after termsymbol ");
outnumber(data);
outcr();
}
error(EUNKNOWN);
enddatarecord:
if (token == NUMBER && s == -1) {
x = -x; /* this is needed because we tokenize only positive numbers */
s = 1;
}
data = here;
datarc++;
here = h;
if (DEBUG) {
outsc("** leaving nextdata with data and here ");
outnumber(data); outspc();
outnumber(here); outcr();
}
}
/*
READ - find data records and insert them to variables
*/
void xread() {
token_t t0; /* remember the left hand side token until the end of the statement, type of the lhs */
lhsobject_t lhs;
mem_t datat; /* the type of the data element */
address_t lendest, lensource, newlength;
int k;
string_t s;
nextdata:
/* look for the variable */
nexttoken();
/* this code evaluates the left hand side - remember type and name */
copyname(&lhs.name, &name);
lefthandside(&lhs);
if (!USELONGJUMP && er) return;
if (DEBUG) {
outsc("** read lefthandside ");
outname(&lhs.name);
outsc(" at here ");
outnumber(here);
outsc(" and data pointer ");
outnumber(data);
outcr();
}
/* if the token after lhs is not a termsymbol or a comma, something is wrong */
if (!termsymbol() && token != ',') {
error(EUNKNOWN);
return;
}
/* remember the token we have draw from the stream */
t0 = token;
/* find the data and assign */
nextdatarecord();
if (!USELONGJUMP && er) return;
/* assign the value to the lhs - somewhat redundant code to assignment */
switch (token) {
case NUMBER:
/* a number is stored on the stack */
assignnumber2(&lhs, x);
break;
case STRING:
if (lhs.name.token != STRINGVAR) {
/* we read a string into a numerical variable */
if (sr.address) assignnumber2(&lhs, memread2(sr.address));
else assignnumber2(&lhs, *sr.ir);
} else {
/* we have all we need in sr */
/* the destination address of the lefthandside, on the fly create included */
getstring(&s, &lhs.name, lhs.i, lhs.j);
if (!USELONGJUMP && er) return;
/* the length of the lefthandside string */
lendest = s.length;
if (DEBUG) {
outsc("* read stringcode "); outname(&lhs.name); outcr();
outsc("** read source string length "); outnumber(sr.length); outcr();
outsc("** read dest string length "); outnumber(s.length); outcr();
outsc("** read dest string dimension "); outnumber(s.strdim); outcr();
}
/* does the source string fit into the destination */
if ((lhs.i + sr.length - 1) > s.strdim) {
error(EORANGE);
return;
}
/* now write the string */
assignstring(&s, &sr, sr.length);
/* classical Apple 1 behaviour is string truncation in substring logic */
newlength = lhs.i + sr.length - 1;
setstringlength(&lhs.name, newlength, lhs.j);
}
break;
default:
error(EUNKNOWN);
return;
}
/* next list item */
if (t0 == ',') goto nextdata;
/* no nexttoken here as we have already a termsymbol */
if (DEBUG) {
outsc("** leaving xread with "); outnumber(token); outcr();
outsc("** at here "); outnumber(here); outcr();
outsc("** and data pointer "); outnumber(data); outcr();
}
/* restore the token for further processing */
token = t0;
}
/*
RESTORE sets the data pointer to zero right now
*/
void xrestore() {
short rec;
nexttoken();
/* a plain restore */
if (termsymbol()) {
data = 0;
datarc = 1;
return;
}
/* something with an argument */
expression();
if (!USELONGJUMP && er) return;
/* we search a record */
rec = pop();
/* if we need to search backward, back to the beginning */
if (rec < datarc) {
data = 0;
datarc = 1;
}
/* advance to the record or top */
while (datarc < rec && data < top) nextdatarecord();
/* token is poisoned after nextdatarecord, need to cure this here */
nexttoken();
}
/*
DEF a function, functions are tokenized as FN ARRAYVAR to make
name processing easy.
*/
void xdef() {
address_t a;
name_t function; /* the name of the function */
name_t variable; /* the name of the argument */
/* do we define a function */
if (!expect(TFN, EUNKNOWN)) return;
/* the name of the function, it is tokenized as an array */
if (!expect(ARRAYVAR, EUNKNOWN)) return;
copyname(&function, &name);
function.token = TFN; /* set the right type here */
/* the argument variable */
if (!expect('(', EUNKNOWN)) return;
nexttoken();
if (token == ')') {
zeroname(&variable);
} else if (token == VARIABLE) {
copyname(&variable, &name);
nexttoken();
} else {
error(EUNKNOWN);
return;
}
if (token != ')') {
error(EUNKNOWN);
return;
}
/* which type of function do we store is found in token */
nexttoken();
/* ready to store the function */
if (DEBUG) {
outsc("** DEF FN with function ");
outname(&function);
outsc(" and argument ");
outname(&variable);
outsc(" at here ");
outnumber(here);
outsc(" and token is ");
outnumber(token);
outcr();
}
/* find the function, we allow redefinition, currently only functions with 1 argument */
if ((a = bfind(&function)) == 0) a = bmalloc(&function, 1);
if (DEBUG) {
outsc("** found function structure at ");
outnumber(a);
outcr();
}
if (!USELONGJUMP && er) return;
/* no more memory */
if (a == 0) {
error(EVARIABLE);
return;
}
/* store the payload */
/* first the jump address */
setaddress(a, memwrite2, here);
a = a + addrsize;
/* the type of the return value - at the moment only numbers */
if (token == '=')
memwrite2(a++, VARIABLE);
else
memwrite2(a++, 0);
/* store the number of variables */
memwrite2(a++, 1);
/* store the type and the entire name of the variables */
memwrite2(a++, variable.token);
setname_pgm(a, &variable);
a = a + sizeof(name_t) - 1; /* reserves space for redefinition of functions with different variable */
/* skip the function body during defintion */
if (token == '=') {
while (!termsymbol()) nexttoken();
} else {
#if defined(HASMULTILINEFUNCTIONS)
while (token != TFEND) {
nexttoken();
if (token == TDEF || token == EOL) {
error(EFUN);
return;
}
}
nexttoken();
#else
error(EFUN);
return;
#endif
}
}
/*
FN function evaluation, this is a call from factor or directly from
statement, the variable m tells xfn which one it is. 0 is from
factor and 1 is from statement.
This mechanism is only needed in multiline functions. In this case,
a new interpreter instance is started with statement(). The variable
m decides whether the stack should contain a return value (call from factor)
or should be empty.
The new function code has local variable capability of the new heap.
*/
void xfn(mem_t m) {
address_t a;
address_t h1, h2;
name_t variable;
token_t type;
/* the name of the function and its address */
if (!expect(ARRAYVAR, EUNKNOWN)) return;
name.token = TFN;
a = bfind(&name);
if (a == 0) {
error(EUNKNOWN);
return;
}
if (DEBUG) {
outsc("** in xfn found function ");
outname(&name);
outsc(" at ");
outnumber(a);
outcr();
}
/* and the argument */
if (!expect('(', EUNKNOWN)) return;
nexttoken();
/* if there is no argument, set it to zero */
if (token == ')') {
push(0);
} else {
expression();
if (!USELONGJUMP && er) return;
}
if (token != ')') {
error(EUNKNOWN);
return;
}
/* where is the function code */
h1 = getaddress(a, memread2);
a = a + addrsize;
if (DEBUG) {
outsc("** found function address ");
outnumber(h1);
outcr();
}
/* which type of function do we have*/
type = memread2(a++);
if (DEBUG) {
outsc("** found function type ");
outnumber(type);
outcr();
}
/* the number of variables is always one here */
a++;
/* what is the name of the variable, direct read as getname also gets a token */
/* skip the type here as not needed*/
// zeroname(&variable); /* fixes the obscure function namehandling bug not needed any more with copyname in place */
variable.token = memread2(a++);
(void) getname(a, &variable, memread2);
a = a + sizeof(name_t) - 1;
if (DEBUG) {
outsc("** found function variable ");
outname(&variable);
outcr();
}
/* create a local variable and store the value in it if there is a variable */
if (variable.c[0]) {
if (!bmalloc(&variable, 0)) {
error(EVARIABLE);
return;
}
setvar(&variable, pop());
} else {
/* create a dummy variable to make sure local variables are cleaned up */
variable.token = VARIABLE;
variable.c[0] = '_';
variable.c[1] = 0;
variable.l = 1;
if (!bmalloc(&variable, 0)) {
error(EVARIABLE);
return;
}
}
/* store here and then evaluate the function */
h2 = here;
here = h1;
/*
* For simple singleline function, we directly do expression evaluation.
* This is inexpensive as no new interpreter instance is started.
*/
if (type == VARIABLE) {
if (DEBUG) {
outsc("** evaluating expression at ");
outnumber(here);
outcr();
}
if (!expectexpr()) return;
} else {
#ifdef HASMULTILINEFUNCTIONS
/*
* Here comes the tricky part, we start a new interpreter instance.
* For multiline functions we generate a new interpreter instance by
* calling statement(). The variable m decides whether the stack should
* contain a return value (call from factor) or should be empty.
* fncontext counts and limits the depth of function calls. This is
* important to avoid stack overflow. For this reason statement()
* should not allocate a lot of memory on the C stack.
*/
if (DEBUG) {
outsc("** starting a new interpreter instance ");
outcr();
}
nexttoken();
fncontext++;
if (fncontext > FNLIMIT) {
error(EFUN);
return;
}
statement();
if (!USELONGJUMP && er) return;
if (fncontext > 0) fncontext--; else error(EFUN);
#else
error(EFUN);
return;
#endif
}
/* now that all the function stuff is done, return to here and set the variable right */
here = h2;
(void) bfree(&variable);
/* now, depending on how this was called, make things right, we remove
the return value from the stack and call nexttoken */
if (m == 1) {
pop();
nexttoken();
}
}
/*
ON is a bit like IF
*/
void xon() {
number_t cr, tmp;
int ci;
token_t t;
int line = 0;
/* ON can do the ON ERROR and ON EVENT commands as well, in this BASIC
ERROR and EVENT can also be used without the ON */
nexttoken();
switch (token) {
#ifdef HASERRORHANDLING
case TERROR:
xerror();
return;
#endif
#ifdef HASEVENTS
case TEVENT:
xevent();
return;
#endif
default:
expression();
if (!USELONGJUMP && er) return;
}
/* the result of the condition, can be any number even large */
cr = pop();
if (DEBUG) {
outsc("** in on condition found ");
outnumber(cr);
outcr();
}
/* is there a goto or gosub */
if (token != TGOSUB && token != TGOTO) {
error(EUNKNOWN);
return;
}
/* remember if we do gosub or goto */
t = token;
/* how many arguments have we got here */
nexttoken();
parsearguments();
if (!USELONGJUMP && er) return;
if (args == 0) {
error(EARGS);
return;
}
/* do we have more arguments then the condition? */
if (cr > args && cr <= 0) ci = 0; else ci = (int)cr;
/* now find the line to jump to and clean the stack, reuse cr
we need to clean the stack here completely, therefore complete the loop
ERROR handling is needed for the trapping mechanism. No using popaddress()
here, because of the needed stack cleanup. Unclear is this precaution is
really needed.
*/
while (args) {
tmp = pop();
if (args == ci) {
if (tmp < 0) er = ELINE;
line = tmp;
}
args--;
}
if (!USELONGJUMP && er) return;
if (DEBUG) {
outsc("** in on found line as target ");
outnumber(line);
outcr();
}
/* no line found to jump to */
if (line == 0) {
nexttoken();
return;
}
/* prepare for the jump */
if (t == TGOSUB) pushgosubstack(0);
if (!USELONGJUMP && er) return;
findline(line);
if (!USELONGJUMP && er) return;
/* goto in interactive mode switched to RUN mode
no clearing of variables and stacks */
if (st == SINT) st = SRUN;
}
#endif
/* the structured BASIC extensions, WHILE, UNTIL, and SWITCH */
#ifdef HASSTRUCT
void xwhile() {
/* what? */
if (DEBUG) {
outsc("** in while ");
outnumber(here);
outspc();
outnumber(token);
outcr();
}
/* interactively we need to save the buffer location */
if (st == SINT) here = bi - ibuffer;
/* save the current location and token type, here points to the condition, name is irrelevant */
pushloop(0, TWHILE, here, 0, 0);
/* is there a valid condition */
if (!expectexpr()) return;
/* if false, seek WEND and clear the stack*/
if (!pop()) {
droploop();
if (st == SINT) bi = ibuffer + here;
nexttoken();
findbraket(TWHILE, TWEND);
nexttoken();
}
}
void xwend() {
blocation_t l;
bloop_t* loop;
/* remember where we are */
pushlocation(&l);
/* back to the condition */
loop = activeloop();
if (!USELONGJUMP && er) return;
/* is this a while loop */
if (loop->var.token != TWHILE ) {
error(TWEND);
return;
}
/* interactive run or program run */
if (st == SINT) bi = ibuffer + loop->here; else here = loop->here;
/* is there a valid condition */
if (!expectexpr()) return;
/* if false, seek WEND */
if (!pop()) {
droploop();
poplocation(&l);
nexttoken();
}
}
void xrepeat() {
/* what? */
if (DEBUG) {
outsc("** in repeat ");
outnumber(here);
outspc();
outnumber(token);
outcr();
}
/* interactively we need to save the buffer location */
if (st == SINT) here = bi - ibuffer;
/* save the current location and token type, here points statement after repeat */
pushloop(0, TREPEAT, here, 0, 0);
/* we are done here */
nexttoken();
}
void xuntil() {
blocation_t l;
bloop_t* loop;
/* is there a valid condition */
if (!expectexpr()) return;
/* remember the location */
pushlocation(&l);
/* look on the stack */
loop = activeloop();
if (!USELONGJUMP && er) return;
/* if false, go back to the repeat */
if (!pop()) {
/* the right loop type ? */
if (loop->var.token != TREPEAT) {
error(TUNTIL);
return;
}
/* correct for interactive */
if (st == SINT) bi = ibuffer + loop->here; else here = loop->here;
} else {
/* back to where we were */
droploop();
poplocation(&l);
}
nexttoken(); /* a bit of evil here, hobling over termsymbols */
}
void xswitch() {
number_t r;
mem_t match = 0;
mem_t swcount = 0;
blocation_t l;
/* lets look at the condition */
if (!expectexpr()) return;
r = pop();
/* remember where we are */
pushlocation(&l);
/* seek the first case to match the condition */
while (token != EOL) {
if (token == TSWEND) break;
/* nested SWITCH - skip them all*/
if (token == TSWITCH) {
if (DEBUG) {
outsc("** in SWITCH - nesting found ");
outcr();
}
nexttoken();
findbraket(TSWITCH, TSWEND);
if (DEBUG) {
outsc("** in SWITCH SWEND found at ");
outnumber(here);
outcr();
}
if (!USELONGJUMP && er) return;
}
/* a true case */
if (token == TCASE) {
/* more sophisticated, case can have an argument list */
nexttoken();
parsearguments();
if (DEBUG) {
outsc("** in CASE found ");
outnumber(args);
outsc(" arguments");
outcr();
}
if (!USELONGJUMP && er) return;
if (args == 0) {
error(TCASE);
return;
}
while (args > 0) {
if (pop() == r) match = 1;
args--;
}
if (match) {
return;
}
}
nexttoken();
}
/* return to the original location and continue if no case is found */
poplocation(&l);
}
/* a nacked case statement always seeks the end of the switch,
currently SWITCH statements cannot be nested. */
void xcase() {
while (token != EOL) {
nexttoken();
if (token == TSWEND) break;
}
}
#endif
/*
statement processes an entire basic statement until the end
of the line.
The statement loop is a bit odd and requires some explanation.
A statement function called in the central switch here must either
call nexttoken as its last action to feed the loop with a new token
and then break or it must return which means that the rest of the
line is ignored. A function that doesn't call nexttoken and just
breaks causes an infinite loop.
statement is called once in interactive mode and terminates
at end of a line.
*/
void statement() {
mem_t xc;
if (DEBUG) bdebug("statement \n");
/* we can long jump out out any function now, making error handling easier */
/* if we return here with a long jump, only the error handler is triggered */
/* this mechanism always branches to the highest context */
#if USELONGJUMP == 1
if (fncontext == 0) if (setjmp(sthook)) goto errorhandler;
#endif
/* the core loop processing commands */
while (token != EOL) {
#ifdef HASSTEFANSEXT
/* debug level 1 happens only in the statement loop */
if (debuglevel == 1) {
debugtoken();
outcr();
}
#endif
switch (token) {
case ':':
case LINENUMBER:
nexttoken();
break;
/* Palo Alto BASIC language set + BREAK */
case TPRINT:
xprint();
break;
case TLET:
nexttoken();
if ((token != ARRAYVAR) && (token != STRINGVAR) && (token != VARIABLE)) {
error(EUNKNOWN);
break;
}
case STRINGVAR:
case ARRAYVAR:
case VARIABLE:
assignment();
break;
case TINPUT:
xinput();
break;
case TRETURN:
#ifndef HASMULTILINEFUNCTIONS
xreturn();
#else
if (fncontext > 0) {
nexttoken();
if (termsymbol()) {
push(0);
}
else expression();
return; /* this returns from statement and ends one interpreter instance */
} else
xreturn(); /* while this happens inside the instance */
#endif
break;
#ifndef HASMULTILINEFUNCTIONS
case TGOSUB:
case TGOTO:
xgoto();
break;
#else
case TGOSUB:
if (fncontext > 0) {
error(EFUN);
return;
}
case TGOTO:
xgoto();
break;
#endif
case TIF:
xif();
break;
case TFOR:
xfor();
break;
case TNEXT:
xnext();
break;
case TBREAK:
xbreak();
break;
case TSTOP:
case TEND: /* return here because new input is needed, end as a block end is handles elsewhere */
*ibuffer = 0; /* clear ibuffer - this is a hack */
st = SINT; /* switch to interactive mode */
eflush(); /* if there is an EEPROM dummy, flush it here (protects flash storage!) */
ofileclose();
nexttoken();
if (token == TSTOP) {
restartsystem();
}
*ibuffer = 0; /* clear ibuffer - this is a hack */
st = SINT; /* switch to interactive mode */
return; /* leave the interpreter instance */
case TLIST:
xlist();
break;
case TNEW: /* return here because new input is needed */
xnew();
return;
case TCONT: /* cont behaves differently in interactive and in run mode */
if (st == SRUN || st == SERUN) {
xcont();
break;
} /* no break here, because interactively CONT=RUN minus CLR */
case TRUN:
xrun();
return;
case TREM:
xrem();
break;
/* Apple 1 language set */
#ifdef HASAPPLE1
case TDIM:
xdim();
break;
case TCLR:
xclr();
break;
case TTAB:
case TSPC:
xtab();
break;
case TPOKE:
xpoke();
break;
#endif
/* Stefan's tinybasic additions */
case TSAVE:
xsave();
break;
case TLOAD:
xload(0);
if (st == SINT) return; /* interactive load doesn't like break as the ibuffer is messed up; */
else break;
#ifdef HASSTEFANSEXT
case TDUMP:
xdump();
break;
case TGET:
xget();
break;
case TPUT:
xput();
break;
case TSET:
xset();
break;
case TNETSTAT:
xnetstat();
break;
case TCLS:
ax = od;
/* if we have a display it is the default for CLS */
#if defined(DISPLAYDRIVER) || defined(GRAPHDISPLAYDRIVER)
od = ODSP;
#endif
outch(12);
od = ax;
nexttoken();
break;
case TLOCATE:
xlocate();
break;
#endif
#ifdef HASUSRCALL
/* low level functions */
case TCALL:
xcall();
break;
#endif
/* Arduino IO */
#ifdef HASARDUINOIO
case TDWRITE:
xdwrite();
break;
case TAWRITE:
xawrite();
break;
case TPINM:
xpinm();
break;
case TDELAY:
xdelay();
break;
#ifdef HASTONE
case TTONE:
xtone();
break;
#endif
#ifdef HASPULSE
case TPULSE:
xpulse();
break;
#endif
#endif
/* BASIC DOS function */
#ifdef HASFILEIO
case TCATALOG:
xcatalog();
break;
case TDELETE:
xdelete();
break;
case TOPEN:
xopen();
break;
case TCLOSE:
xclose();
break;
case TFDISK:
xfdisk();
break;
#endif
/* graphics */
#ifdef HASGRAPH
case TCOLOR:
xcolor();
break;
case TPLOT:
xplot();
break;
case TLINE:
xline();
break;
case TRECT:
xrect();
break;
case TCIRCLE:
xcircle();
break;
case TFRECT:
xfrect();
break;
case TFCIRCLE:
xfcircle();
break;
#endif
#ifdef HASDARTMOUTH
case TDATA:
xdata();
break;
case TREAD:
xread();
break;
case TRESTORE:
xrestore();
break;
case TDEF:
xdef();
break;
case TON:
xon();
break;
#ifdef HASMULTILINEFUNCTIONS
case TFN:
xfn(1);
break;
case TFEND:
/* we leave the statement loop and return to the calling expression() */
/* if the function is ended with FEND we return 0 */
if (fncontext == 0) {
error(EFUN);
return;
}
else {
push(0);
return;
}
break;
#endif
#endif
#ifdef HASSTEFANSEXT
case TELSE:
xelse();
break;
#endif
#ifdef HASDARKARTS
case TEVAL:
xeval();
break;
#endif
#ifdef HASERRORHANDLING
case TERROR:
xerror();
break;
#endif
#ifdef HASIOT
case TSLEEP:
xsleep();
break;
case TWIRE:
xwire();
break;
#endif
#ifdef HASTIMER
case TAFTER:
case TEVERY:
xtimer();
break;
#endif
#ifdef HASEVENTS
case TEVENT:
xevent();
break;
#endif
#ifdef HASSTRUCT
case TWHILE:
xwhile();
break;
case TWEND:
xwend();
break;
case TREPEAT:
xrepeat();
break;
case TUNTIL:
xuntil();
break;
case TSWITCH:
xswitch();
break;
case TCASE:
xcase();
break;
case TSWEND:
case TDO:
case TDEND:
nexttoken();
break;
#endif
#ifdef HASEDITOR
case TEDIT:
xedit();
break;
#endif
#ifdef HASHELP
case THELP:
xhelp();
break;
#endif
default:
/* strict syntax checking */
error(EUNKNOWN);
goto errorhandler;
}
/*
after each statement we check on a break character
on an Arduino entering "#" at runtime stops the program
for BREAKINBACKGROUND we do this in the background loop
to avoid slowing down.
*/
#if defined(BREAKCHAR)
#ifndef BREAKINBACKGROUND
if (checkch() == BREAKCHAR) {
st = SINT;
if (od == 1) serialflush(); else xc = inch();
return;
}
#else
if (breakcondition) {
breakcondition = 0;
st = SINT;
if (od == 1) serialflush(); else xc = inch();
return;
}
#endif
#endif
/* and after each statement, check the break pin */
#if defined(BREAKPIN)
if (getbreakpin() == 0) {
st = SINT;
return;
};
#endif
/* and then there is also signal handling on some platforms */
#if defined(POSIXSIGNALS)
if (breaksignal) {
st = SINT;
breaksignal = 0;
serialflush();
outcr();
return;
}
#endif
/* yield after each statement which is a 10-100 microsecond cycle
on Arduinos and the like, all background tasks are handled in byield */
byield();
/* if error handling is compiled into the code, errors can be trapped here */
errorhandler:
#ifdef HASERRORHANDLING
if (er) {
if (st != SINT) {
erh = er;
er = 0;
switch (berrorh.type) {
case TCONT:
while (!termsymbol()) nexttoken();
break;
case TGOTO:
findline(berrorh.linenumber);
berrorh.type = 0;
berrorh.linenumber = 0;
if (er) return;
break;
case 0:
return;
default:
nexttoken();
}
} else
return;
}
#else
/* when an error is encountered the statement loop is ended */
if (er) return;
#endif
/*
if we run error free, interrupts and times can be processed
We can savely interrupt and return only if here points either to
a termsymbol : or LINENUMBER. NEXT is a special case. We need to
catch this here because empty FOR loops never even have a termsymbol
a ":"" is swallowed after FOR. This is probably also true for
WHILE and REPEAT loops but has not been tested yet.
The interrupts are only triggered in fncontext 0, i.e. in the
main loop. While in functions, all interrupts are disabled.
*/
if ((token == LINENUMBER || token == ':' || token == TNEXT) && (st == SERUN || st == SRUN)) {
/* timer functions are processed before events */
#ifdef HASTIMER
/* after is always processed before every */
if (after_timer.enabled && fncontext == 0) {
if (millis() > after_timer.last + after_timer.interval) {
after_timer.enabled = 0;
if (after_timer.type == TGOSUB) {
if (token == TNEXT || token == ':') here--;
if (token == LINENUMBER) here -= (1 + sizeof(address_t));
pushgosubstack(0);
}
findline(after_timer.linenumber);
if (er) return;
}
}
/* periodic events */
if (every_timer.enabled && fncontext == 0) {
if (millis() > every_timer.last + every_timer.interval) {
every_timer.last = millis();
if (every_timer.type == TGOSUB) {
if (token == TNEXT || token == ':') here--;
if (token == LINENUMBER) here -= (1 + sizeof(address_t));
pushgosubstack(0);
if (er) return;
}
findline(every_timer.linenumber);
if (er) return;
}
}
#endif
/* the branch code for interrupts, we round robin through the event list */
#ifdef HASEVENTS
/* interrupts */
if (nevents > 0 && events_enabled && fncontext == 0) {
for (xc = 0; xc < EVENTLISTSIZE; xc++) {
if (eventlist[ievent].pin && eventlist[ievent].enabled && eventlist[ievent].active) {
if (eventlist[ievent].type == TGOSUB) {
if (token == TNEXT || token == ':') here--;
if (token == LINENUMBER) here -= (1 + sizeof(address_t));
pushgosubstack(TEVENT);
if (er) return;
}
findline(eventlist[ievent].linenumber); /* here we jump to the new line */
if (er) return;
eventlist[ievent].active = 0;
enableevent(eventlist[ievent].pin); /* events are disabled in the interrupt function, here they are activated again */
events_enabled = 0; /* once we have jumped, we keep the events in BASIC off until reenabled by the program */
break;
}
ievent = (ievent + 1) % EVENTLISTSIZE;
}
}
#endif
}
}
}
/*
the banner message
*/
void displaybanner() {
int i;
printmessage(MGREET); outspc();
printmessage(EOUTOFMEMORY); outspc();
if (memsize < maxnum) outnumber(memsize + 1); else {
outnumber(memsize / 1024 + 1);
outch('k');
}
outspc();
#ifdef HASERRORHANDLING
printmessage(EEEPROM);
outspc();
#endif
outnumber(elength());
outcr();
#ifdef HASHELP
outsc(getmessage(MLANGSET));
outsc(getmessage(MBASICLANGSET)); outcr();
outsc("IO: ");
for (i = 0; i < 32; i++) {
if (iostat(i)) {
outnumber(i); outspc();
}
}
outcr();
#endif
}
/*
the setup routine - Arduino style
*/
void setup() {
/* start measureing time */
timeinit();
/* initialize the event system */
#ifdef HASEVENTS
initevents();
#endif
/* init all io functions */
ioinit();
#ifdef FILESYSTEMDRIVER
// if (fsstat(1) == 1 && fsstat(2) > 0) outsc("Filesystem started\n");
#endif
/* setup for all non BASIC stuff */
bsetup();
/* get the BASIC memory, either as memory array with
ballocmem() or as an SPI serical memory */
#if (defined(SPIRAMINTERFACE) || defined(SPIRAMSIMULATOR)) && (!defined(MEMSIZE) || MEMSIZE == 0)
himem = memsize = spirambegin();
#else
#if defined(EEPROMMEMINTERFACE)
/*
for an EEPROMMEM system, the memory consists of the
EEPROM from 0 to elength()-eheadersize and then the RAM.
*/
himem = memsize = ballocmem() + (elength() - eheadersize);
#else
himem = memsize = ballocmem();
#endif
#endif
#ifndef EEPROMMEMINTERFACE
if (DEBUG) {
outsc("** on startup, memsize is ");
outnumber(memsize);
outcr();
}
/* be ready for a new program if we run on RAM*/
xnew();
if (DEBUG) {
outsc("** on startup, ran xnew ");
outcr();
}
#else
/* if we run on an EEPROM system, more work is needed */
if (eread(0) == 0 || eread(0) == 1) { /* have we stored a program and don't do new */
top = getaddress(1, beread);
resetbasicstate(); /* the little brother of new, reset the state but let the program memory be */
for (address_t a = elength(); a < memsize; a++) memwrite2(a, 0); /* clear the heap i.e. the basic RAM*/
} else {
eupdate(0, 0); /* now we have stored a program of length 0 */
setaddress(1, beupdate, 0);
xnew();
}
#endif
/* check if there is something to autorun and prepare
the interpreter to got into autorun once loop is reached */
if (!autorun()) displaybanner();
/* activate the BREAKPIN */
breakpinbegin();
}
/*
the loop routine for interactive input
*/
void loop() {
/*
autorun state was found in setup, autorun now but only once
autorun BASIC programs return to interactive after completion
autorun code always must loop in itself
*/
if (st == SERUN) {
xrun();
/* on an EEPROM system we don't set top to 0 here */
#ifndef EEPROMMEMINTERFACE
top = 0;
#endif
st = SINT;
} else if (st == SRUN) {
here = 0;
xrun();
st = SINT;
}
/* always return to default io channels once interactive mode is reached */
iodefaults();
form = 0;
/* the prompt and the input request */
printmessage(MPROMPT);
(void) ins(ibuffer, BUFSIZE - 2);
/* tokenize first token from the input buffer */
bi = ibuffer;
nexttoken();
/* a number triggers the line storage, anything else is executed */
if (token == NUMBER) {
ax = x;
storeline();
/* on an EEPROM system we store top after each succesful line insert */
#ifdef EEPROMMEMINTERFACE
setaddress(1, beupdate, top);
#endif
} else {
/* st=SINT; */
statement();
st = SINT;
}
/* here, at last, all errors need to be catched and back to interactive input*/
if (er) reseterror();
}
/* if we are not on an Arduino, we need a main */
#ifndef ARDUINO
int main(int argc, char* argv[]) {
/* save the arguments if there are any */
#ifdef HASARGS
bargc = argc;
bargv = argv;
#endif
/* do what an Arduino would do, this loops for every interactive input */
setup();
while (1)
loop();
}
#endif
/*
Arduino style function for non BASIC code to run on the MCU.
All code that needs to run on the MCU independently can be put here.
It works more or less just like the normal loop() and setup().
This is meant for robotics and other device control type of stuff
on the Arduino platform.
On POSIX systems I/O is blocking and therefore bloop() is not called
consistently.
Rules of the game:
- bsetup() is called once during interpreter startup after all
IO subsystems are started and before the BASIC main memory is
allocated. Allocate memory here. Do not allocate a lot of memory
in bloop().
- Never start or restart I/O functions of BASIC in bsetup(),
no Wire.begin(), Serial.begin() etc. If BASIC also uses this
BASIC handles the I/O startup. Things that BASIC does not use
can be started here.
- bloop() is called after every token, during I/O polling and in
DELAY functions.
- The typical call frequency of bloop() is 20 microseconds or faster.
This is fairly constant and reliable.
- The interpreter is robust against code in bloop() that needs a lot
of CPU time. It will simply slow down but it will not break,
unless(!) other I/O systems like network also need background CPU time
and you block bloop for a long time. As a rule of thumb, on network systems
bloop() should return after 1 ms. After bloop() has returned, the interpreter
tries to handle network and USB update stuff.
- Never use delay() in bloop(). Set a counter. Look at the tone
emulation code for examples.
- Never ever call BASIC functions from bloop(). BASIC function will
eventually call byield() which calls bloop() and so forth.
If you need to communicate data into BASIC, use the BASIC main
memory, variables or the USR function mechanism.
- Avoid allocating a lot of memory in bloop().
*/
void bsetup() {
/* put your setup code here, to run once: */
}
void bloop() {
/* put your main code here, to run repeatedly: */
}