search

mystorm-org / BlackIce-II

Software, Firmware and documentation for the myStorm BlackIce-II board
68 stars 8 forks source link

Issues with SRAM example #27

Open bonnefoi opened 3 months ago

bonnefoi commented 3 months ago

Hello,

I've a lot of issues with the SRAM example with the io constraints like sram_addr_to_pad not known.

When I try to change it to ADR in the file sram_io_ice40, I've got an error: chip.blif:322: fatal error: toplevel inout port 'ADR[0]' connected to tristate buffer and driving a net

I know that is old tech by now, but I would like to use SRAM for my PicoRV32 that uses only ~12k of BRAM currently.

Let me know if you could help me. Best regards, Pierre-Francois.

chenz commented 3 months ago

I've had issues before with the examples not working with newer versions of the toolchain.

E.g. with Yosys 0.27, I had to add "-top chip" in the Makefile, because it would no longer pick "chip" implicitly as the top level module.

Also, arachne-pnr is still being used in the Makefile, which has been unmaintained for a while so it would not be surprising that it does not work with more recent Yosys output. You could try to use nextpnr instead.

bonnefoi commented 3 months ago

Thank you very much for your answer !

I've already encountered the issue with the automatic selection of the top circuit with newer version of yosys, but stupid me, I've tried -top top...

It's working now and I can now start to connect it to the SoC.