meuer26 / dos1541

The Commodore 1541 DOS ROM, buildable with cc65

Commodore 1541 DOS ROM Source Code

This is based on the reconstruction of the Comodore 1541 DOS ROM. The source has been adapted to work with the cc65/ca65 assembler. All original symbols and comments are intact.

The history of the repository contains all versions from the 1540 to the 1541-II:

Revision	Part Numbers	Description
1371125	325302-01, 325303-01	1540
1b7ccc4	325302-01, 901229-01	1541 (original)
11fa875	325302-01, 901229-02	1541 (update)
1109aa1	325302-01, 901229-03	1541 (update)
bfaf45a	325302-01, 901229-05	1541 (short board)
bd9aae0	325302-01, 901229-06	1541 (short board, update)
543e4b0	251968-01	1541C (original)
cd67762	251968-02	1541C (updated)
HEAD	251968-03	1541-II

All versions build into the exact ROM images, except for checksum and signature bytes.

This makes this repository not just a great base for custom 1541 DOS ROMs, but also a great resource to research ROM differences.

Building

• Use make to build.
• Requires cc65.
• The resulting file dos.bin is the full $C000-$FFFF image.
• The only differences are the checksum bytes at $C000 and $FEE6 and the signature byte at $FFE5.

Credits

This version is maintained by Michael Steil [email protected], www.pagetable.com