Illegal Opcode Support for the Final Cartridge III Monitor

The monitor built into the Final Cartridge III is one of the best ones for the C64. Some of its unique features are:

  • dumping PETSCII (I comand), character sets (EC) and sprites (ES)
  • F3/F5 for scrolling, including backwards disassembly
  • drive mode (OD) to view and change RAM of a drive and execute code there

I have previously released a reverse-engineered version of the monitor that runs stand-alone on a C64, and an adaptation for the monitor to run on the TED series (C16, C116, Plus/4).

The monitor’s biggest weakness is its lack of support for illegal opcodes. I have now added this support.

The source is available on github:

https://github.com/mist64/final_cartridge

See the build instructions there on how to enable illegal opcode support.

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