PEDISK II

This repository holds reverse engineering work on the PEDISK II from CGRS Microtech, a floppy disk controller for Commodore PET/CBM computers.

Files

• rom_e800.bin is a binary dump of the EPROM.

• rom_e800.asm is a disassembly of it.

Assemble

The .asm files can be assembled with the ACME assembler:

$ acme -v1 --outfile test.bin pedisk2.asm

It should assemble a binary that is identical to the original.

Credits

• Lee Davison did the initial disassembly of the ROM.
• Jim Oldfield provided the 5.25" PEDISK disks from which the DOS code was recovered.
• Mike Naberezny disassembled the 5.25" DOS code, adapted it for 8", and wrote the image tools.
• Steve Hirsch provided help and formatted 8" disks used for early testing.
• Josh Bensadon reverse engineered the original PCB and made the schematic.
• Steve Gray made the replica PCB layout and had boards manufactured.
• Mike Stein built the replica and provided help and input throughout.
• Bill Goble, the original designer of the PEDISK, found and donated the original manuals, schematics, source code, and master disks.