Since the old ISA Hardsid is not being sold anymore, I'll publish some of my research work here. I had plans of designing a PCI version of the Hardsid with full compatibility with the ISA version. Hard Software has recently released their own Hardsid PCI, so my project is now pointless. Well, I still could design my own PCI version, and release the information how to construct such a card, but just now I have much more importants things to do. According to this posting in the CBM hackers mailing list, the Hardsid was originally meant to be free for people to build.

To design a PCI version, I first had to know how the original Hardsid works. I reverse-engineered the ISA card and drew schematics. The hand-drawn schematics were a mess, so I thought of re-drawing them using a PCB design software. At that point I had an interesting idea: I had the schematics on a PCB software, why not to design a PCB of it? Then I would be absolutely certain that schematics are correct.

Schematics (3764x2427 PNG, 146kB)
PCB layout, top (3337x2881 PNG, 55kB)
PCB layout, bottom (3337x2881 PNG, 52kB)
Component placing (1570x829 PNG, 35kB)
Parts list

Picture of a working prototype (JPEG, 73kB)

So, feel free to hack around.