HDTenEightyP/CompuServe · Datasets at Hugging Face

text stringlengths 0 99.6k



10 input"filename";f$

20 open8,8,1,f$

30 fori=1to89:ready

40 print#8,chr$(y);:next

50 close8

100 data173,2,6,65,84,83,48,61,48,13

110 data24,165,34,105,2,133,45,165,35

120 data105,0,133,46,169,1,162,173,160

130 data2,32,189,255,152,170,32,186

140 data255,32,192,255,162,2,32,198

150 data255,162,2,32,201,255,162,249

160 data189,181,1,32,210,255,232,208

170 data247,32,228,255,32,22,231,201

180 data75,208,246,169,2,32,195

190 data255,32,83,228,32,204,255,76

200 data116,164,139,227,181,2



The program LOADs at $02AD, ending at $0303, where it

overwrites the ready mode and input buffer vectors. The latter is changed

to $02B5, the start of the routine. After the LOAD, the BASIC goes to the

new vector, where the correct START OF VARIABLES address is put into $2D,

$2E (it had been changed by the LOAD). Then a 300 baud RS-232 channel is

OPENed, "ATS0=0 <CR>" is sent through it, and the routine waits for the "K"

of "OK" to be received from the modem and printed. Next, the file is

closed, the original vectors are installed, CLRCHN is called, and the JMP

is made to ready mode.



[This program (tokenized BASIC) is in LIB 12 under the name NOANSR.BIN]

This file will instruct you on how to modify the 1764 RAMTEST program to test all 512K of your REU. This, of course, would only apply if you have added the additional 256K to the 1764. Please read 1764.TXT in this library for instructions on that procedure.

First, "1764 RAMTEST.BAS" is a BASIC loader for the program "1764 RAMTEST.BIN" which is a machine language program that does the actual testing of the REU. Second, I will outline three methods of modifying your program to test the entire 512K.

METHOD ONE - Load the program "1764 RAMTEST.BAS". List the program and look at line 500 on up. Make the following changes to your program:

500 :
510 REM LINES 520 AND 530 TEST 512K
520 POKE 33093,7:POKE 33099,33
530 POKE 36003,53:POKE 36004,49:POKE 36005,50
540 :
1000 SYS 32768: REM WE WON'T BE COMING BACK!

Then save this new program back to disk by first scratching the old program and then saving the new. This modification merely pokes new values to the mentioned memory locations after the program "1764 RAMTEST.BIN" has been loaded into memory at location 32768. The ramtest program will now test a eight banks of memory.

METHOD TWO - Using a Disk Editor program (such as Di-Sector) load Track 20, Sector 6 (the 2nd sector of the program) of "1764 RAMTEST.BIN". Change relative byte 75 from $03 to $07. Change relative byte 81 from $11 to $21. Then write this sector back to disk. Now load Track 20, Sector 15 (the 13th sector of the program) of the same program. Change relative bytes 191, 192 and 193 from $32 to $35, $35 to $31 and $36 to $32, respectively. Write this sector back to disk. There i no need for the revised pokes in the BASIC loader program if you use this method. I feel this is a better way to modify this program.

METHOD THREE - Using an Assembler/Monitor load "1764 RAMTEST.BIN" at location 32768. Then change memory locations as follows:
POKE 33093 with $07
POKE 33099 with $21
POKE 36003 with $35
POKE 36004 with $31
POKE 36005 with $32
Then save this program back to disk.

Whichever method you use is your choice. All three will provide you with the means test all 512K of your expanded 1764 REU. Good luck!
HOW TO EXPAND YOUR 1764 FROM 256K TO 512K

The 1764 RAM Expansion Unit (REU) consists of a plug in cartridge and a beefier power supply. This power supply is required because the original C-64 power supply was not designed to meet the current requirements of the additional IC's in the REU. The new power supply is rated at 2.5A at 5 VDC and 1A at 9 VAC. The DC supply was increased for the additional RAM.

The 1764 REU is merely a printed circuit board (PCB) inside a metal housing which is inside the plastic case. This assembly plugs into the Expansion Port of the C-64 or 64-C computers. The PCB is the same board that is used in the 1700 (128K) and the 1750 (512K) Expansions with a couple of differences:

1) The 1764 has only one bank of eight 256K Dynamic Random Access Memory (DRAM) IC's. Each IC holds 256K bits of information; therefore, 8 IC's are needed to obtain 256K bytes.

2) There is a empty bank of 8 positions labelled Bank II on the PCB.

3) There is a resistor (most likely R4) in the 1700 and the 1750 REU's that was omitted in the 1764, apparently due to a small difference in the Expansion Port of the C-128 and the C-64. In spite of this difference there are many C-64 users that have installed the 1750 REU without problems. Please note; you cannot use the original power supply in this manner. You MUST use a power supply that has more current on the DC side.

Commodore likely decided to ship the 1764 with only 256K to keep the price of the unit down and make it attractive to as many C-64 owners as possible. Only by selling a significant quantity of the 1764 would it be possible to entice software companies to support it. The RAMDISK software included with the 1764 is a nice option, but it is not compatible with many software packages since it only supports the 4 file types (PRG, SEQ, USR and REL). The RAMDISK does not support direct track-sector access, which many programs use for loading and other functions.

It is not too difficult for someone with a reasonable knowledge of soldering to install the additional IC's in Bank II on the PCB. You may want to install IC sockets on the board to avoid damaging the DRAMs. Bank I is not in sockets. It is possible to solder the IC's directly into the board without heat damage. If you feel hesitant about doing so, you will probably want to use the sockets.

10 input"filename";f$

20 open8,8,1,f$

30 fori=1to89:ready

40 print#8,chr$(y);:next

50 close8

100 data173,2,6,65,84,83,48,61,48,13

110 data24,165,34,105,2,133,45,165,35

120 data105,0,133,46,169,1,162,173,160

130 data2,32,189,255,152,170,32,186

140 data255,32,192,255,162,2,32,198

150 data255,162,2,32,201,255,162,249

160 data189,181,1,32,210,255,232,208

170 data247,32,228,255,32,22,231,201

180 data75,208,246,169,2,32,195

190 data255,32,83,228,32,204,255,76

200 data116,164,139,227,181,2

The program LOADs at $02AD, ending at $0303, where it

overwrites the ready mode and input buffer vectors. The latter is changed

to $02B5, the start of the routine. After the LOAD, the BASIC goes to the

new vector, where the correct START OF VARIABLES address is put into $2D,

$2E (it had been changed by the LOAD). Then a 300 baud RS-232 channel is

OPENed, "ATS0=0 <CR>" is sent through it, and the routine waits for the "K"

of "OK" to be received from the modem and printed. Next, the file is

closed, the original vectors are installed, CLRCHN is called, and the JMP

is made to ready mode.

[This program (tokenized BASIC) is in LIB 12 under the name NOANSR.BIN]

This file will instruct you on how to modify the 1764 RAMTEST program to test all 512K of your REU. This, of course, would only apply if you have added the additional 256K to the 1764. Please read 1764.TXT in this library for instructions on that procedure.

First, "1764 RAMTEST.BAS" is a BASIC loader for the program "1764 RAMTEST.BIN" which is a machine language program that does the actual testing of the REU. Second, I will outline three methods of modifying your program to test the entire 512K.

METHOD ONE - Load the program "1764 RAMTEST.BAS". List the program and look at line 500 on up. Make the following changes to your program:

500 :

510 REM LINES 520 AND 530 TEST 512K

520 POKE 33093,7:POKE 33099,33

530 POKE 36003,53:POKE 36004,49:POKE 36005,50

540 :

1000 SYS 32768: REM WE WON'T BE COMING BACK!

Then save this new program back to disk by first scratching the old program and then saving the new. This modification merely pokes new values to the mentioned memory locations after the program "1764 RAMTEST.BIN" has been loaded into memory at location 32768. The ramtest program will now test a eight banks of memory.

METHOD TWO - Using a Disk Editor program (such as Di-Sector) load Track 20, Sector 6 (the 2nd sector of the program) of "1764 RAMTEST.BIN". Change relative byte 75 from $03 to $07. Change relative byte 81 from $11 to $21. Then write this sector back to disk. Now load Track 20, Sector 15 (the 13th sector of the program) of the same program. Change relative bytes 191, 192 and 193 from $32 to $35, $35 to $31 and $36 to $32, respectively. Write this sector back to disk. There i no need for the revised pokes in the BASIC loader program if you use this method. I feel this is a better way to modify this program.

METHOD THREE - Using an Assembler/Monitor load "1764 RAMTEST.BIN" at location 32768. Then change memory locations as follows:

POKE 33093 with $07

POKE 33099 with $21

POKE 36003 with $35

POKE 36004 with $31

POKE 36005 with $32

Then save this program back to disk.

Whichever method you use is your choice. All three will provide you with the means test all 512K of your expanded 1764 REU. Good luck!

HOW TO EXPAND YOUR 1764 FROM 256K TO 512K

The 1764 RAM Expansion Unit (REU) consists of a plug in cartridge and a beefier power supply. This power supply is required because the original C-64 power supply was not designed to meet the current requirements of the additional IC's in the REU. The new power supply is rated at 2.5A at 5 VDC and 1A at 9 VAC. The DC supply was increased for the additional RAM.

The 1764 REU is merely a printed circuit board (PCB) inside a metal housing which is inside the plastic case. This assembly plugs into the Expansion Port of the C-64 or 64-C computers. The PCB is the same board that is used in the 1700 (128K) and the 1750 (512K) Expansions with a couple of differences:

1) The 1764 has only one bank of eight 256K Dynamic Random Access Memory (DRAM) IC's. Each IC holds 256K bits of information; therefore, 8 IC's are needed to obtain 256K bytes.

2) There is a empty bank of 8 positions labelled Bank II on the PCB.

3) There is a resistor (most likely R4) in the 1700 and the 1750 REU's that was omitted in the 1764, apparently due to a small difference in the Expansion Port of the C-128 and the C-64. In spite of this difference there are many C-64 users that have installed the 1750 REU without problems. Please note; you cannot use the original power supply in this manner. You MUST use a power supply that has more current on the DC side.

Commodore likely decided to ship the 1764 with only 256K to keep the price of the unit down and make it attractive to as many C-64 owners as possible. Only by selling a significant quantity of the 1764 would it be possible to entice software companies to support it. The RAMDISK software included with the 1764 is a nice option, but it is not compatible with many software packages since it only supports the 4 file types (PRG, SEQ, USR and REL). The RAMDISK does not support direct track-sector access, which many programs use for loading and other functions.

It is not too difficult for someone with a reasonable knowledge of soldering to install the additional IC's in Bank II on the PCB. You may want to install IC sockets on the board to avoid damaging the DRAMs. Bank I is not in sockets. It is possible to solder the IC's directly into the board without heat damage. If you feel hesitant about doing so, you will probably want to use the sockets.