Looking at this on the GSoC page:
flashrom support for Willem hardware
Haha, I'd so love to see this.
For a base to work off of, look at firebrand:
http://www.astro.gla.ac.uk/~paulm/Code/eprom.html
You may even be able to google for an older version of the original control program with source.
Also look at the sivava "PCB45" variant as well. This site has info (and schematics with differences highlighted) on how to convert a PCB3B (for which schematics is/was available) to a PCB45: http://www.msxpro.com/py2bbs/willem_pcb45en.php
There are four versions that we can easily get schematics for - original willem, PCB3B, a simplified, flash-only "EzoFlash", and the PCB45 conversion above. There are newer variants but they are proprietary. I'd love to see support for these four implemented.
From what I read it may be a product of the shady parts of Internet. At
least it is sort of open and easily accessible. I first built EzoFlash on a breadboard to flash a firmware for my infamous Apex 600A DVD player, and then built a PCB3B on a crudely made PCB, that I am using right now to flash 440BX RAM initialization code for boot testing.
Have fun.
Keith