Are you all that hard up for dev hardware?
I wouldnt mind making a handful for a few peeps just to see if they like it or not.
The only thing I dont like about it is that the people that I use to make the pcb boards dont cut slots into it that are needed for that cart connecter.(they can do it but its a whole other service and they charge a premium as most other pcb houses that i know) It really needs a precise cut for it to work when you plug it in. What I did is just use a moto dremel of course and cut the cart edge as best I could. Ive cut too much on mine so you have to insert it carefully for it to line up with the contacts. You can hear the contacts slide off when you dont insert it straight and amazingly ive never managed to fry the cart slot.
Ive made it so it will fit in a AR cart except you will have to cut some more off the top for the usb connecter. Its been a while since I looked but I think I might need to move some of the chips around for this plastic 'divot' in the middle.
Ill have to look around but Im pretty sure Ive got another blank board and maybe enuf parts to complete another. If someone wants to spare a few bucks they can get it.
On the subject of pc comms card I did make a pci version of that ISA card. It really wasnt hard at all. Theres a place called
http://www.fpga4fun.com/ that has a PCI card with a fpga on it for experiments. He had some example code showing how to make some memory mapped IO ports and it was trivial to make into a comms card clone.
Needless to say it worked as well as the original. Like crap! Long cables made it puke. When it did work it was faaast. There just so much noise its crazy. After that I tried using the usb controller directly to the par port on the card. It didnt work very well at all. It basically did what all those freewing clones do and just go through the handshaking that the comms does. It should have worked a lot better but I didnt spend much time on it.
The command line utility I made for the card just has some basic functions
implemented for right now and needs some work but should not be hard at all to add whatever. For linux dudes theres drivers for ezusb devices but youll have to fix all the usb related calls.