#RaspberryPiPico as an Apple II Workstation Card clone idea has taken over my mind! Went off to find the documentation on how it hooks into #ProDOS and can't find anything. Except back when I worked on *two* Apple II emulators for the NeXT I *did* know because I used the same trick to access the Mach filesystem from ProDOS. Where did I learn it? It was over 30 years ago, way before the World Wide Web, search engines, and scanned in books. A2 TIL note? #RetroComputing #VintageComputing