Ok, here goes a crazy idea...
Seeing how thin the ps1 is without the CD drive it would make sense to concentrate on slimming that down. Or removing it completely
I want to replace it with an SD card of ISOs and obviously that requires some extensive hacking.
Emulators have ISO support, and I see no reason why I can't build hardware to intercept requests for block x and return the relevent part of a file.
My question is: I have no idea how the console interacts with the CD drive, where can I find info on this? General concepts plus hardware-level voltages/timing info etc would be great, but I doubt that info exists tbh. It would be nice to be wrong though. Anything you guys can throw my way would be a huge help.