| # How to generate a SPEF (`write_spef`) including coordinate information? | |
| Tool: Parasitics Extraction | |
| Subcategory: SPEF format | |
| ## Conversation | |
| ### xlindo | |
| As the default flow, there is no coordinate information in `*CONN` following each `PORT` in the generated `6_final.spef`, which is not in coincidence with a normal SPEF format. | |
| E.g., no `*C` bolow, | |
|  | |
| ``` | |
| ... | |
| *CONN | |
| *I *572:B I *D sky130_fd_sc_hd__nand2_1 | |
| *I *571:Y O *D sky130_fd_sc_hd__nand2_1 | |
| ... | |
| ``` | |
| Compared with another example in a book, | |
| ``` | |
| *D_NET *5423 2.69358 | |
| *CONN | |
| *I *14207:D I *C 21.7450 94.3150 | |
| *I *14205:D I *C 21.7450 90.4900 | |
| *I *14211:Q O *C 21.4900 83.8800 *D DFFQX1 | |
| *CAP | |
| 1 *5423:10107 *547:12722 0.202686 | |
| 2 *5423:10107 *5116:10594 0.104195 | |
| .... | |
| ``` | |
| Any boss help me? | |
| ### maliberty | |
| Coordinates are optional in spef so this is valid. There is code to generate coordinates but we've never used it. We could try enabling but I can't make any guarantees about what it will produce. Do you have a use model for these or are you just comparing to what a book shows? | |
| ### maliberty | |
| I've added a -coordinates option to write_spef in https://github.com/The-OpenROAD-Project/OpenROAD/pull/3434 | |