Steal Fomu EVT RPi based programming tool?

[mithro]

The Fomu EVT boards where RPi based hats too. Thus @xobs wrote a great little tool for bitbanging SPI to program the iCE40 and SPI on the board (even supports things like QPI mode!).

Take a look at https://github.com/im-tomu/fomu-flash - more than happy to add your board as a target option.

(There is also a tool which builds a RPi image with all the ice40 tooling at https://github.com/im-tomu/fomu-pi-gen too.)

[Wren6991]

I rather wanted the fun of doing this myself! 😢 Thank you for the link to the tools, they look handy. If I end up modifying these then I will submit a PR.

Is there an advantage of the Fomu ROM patching vs icebram?

[xobs]

The advantage to the Fomu ROM patching vs icebram is that it's less to keep track of, and ends up being faster:

• icebram requires an input ROM, an output ROM, an input hexfile, and an input binary. Foboot just requires an input ROM and an input binary.
• The icebram hexfile needs to be in a specific order, and I ended up needing to come up with additional tools to massage the bitstream into the correct format. fomu-flash works on binary images.
• fomu-flash is near-instant, whereas icebram took several seconds

In the end, both accomplish the same thing, so if you're already using icebram then there's no need to change.