I've been using Claude to create an Apple ][ plus emulator implemented as a Java Swing application.
https://github.com/sbabcoc/ReplicApple2Plus
I put together the basics - system, memory expansion cards, disk interface, 80-column card. Back at the dawn of time, I also had a Microsoft SoftCard II coprocessor card, but no one seems to have published the documentation. I found the CP/M 2.28B boot disk here:
https://mirrors.apple2.org.za/ftp.apple.asimov.net/images/cpm/os/Microsoft%20Softcard%20II%20CPM%202.28B.DSK
They also had clear pictures of both sides of the interface card on this site. Using these artifacts, plus whatever other scraps it could find, Claude managed to reverse-engineer the card to produce what appears to be a full functioning emulation.
https://github.com/sbabcoc/SoftCard2
Claude included a bunch of details about what it was able to figure out. I hope folks find this stuff useful, or at least interesting.
I actually found the documentation on Internet Archive.
https://archive.org/details/softcard-ii-installation-and-operations-manual-and-programmers-manual-1/page/n376/mode/1up
Let's start from the beginning:
https://archive.org/details/softcard-ii-installation-and-operations-manual-and-programmers-manual-1/mode/1up