The “Final Cartridge III” has been among the most popular Commodore 64 extensions, providing a floppy speeder, BASIC extensions, a machine language monior, a freezer and even a (rarely used) graphical desktop. The major advantage compared to other C64 cartridges is the consistent way in which the Final Cartridge III extends the C64 experience.
As it turns out, there are several undocumented instructions implemented in the Final Cartridge III.
The DOS”$” command passes all characters following the “$” to the disk drive, allowing the user to specify filters, like this:
DOS"$A*" :REM SHOW ALL FILES THAT START WITH "A"
This feature is not available for the “@” command in the monitor.
The 26 second fast format known from the “DESKTOP” GUI is also available from the command line. Note that this also works with the “@” command in the monitor. If the ID is omitted, this only overwrites BAM and directory, just like the “N” command.
This commands renames the disk without erasing it. The ID can be up to 5 characters, so the default “2A” can be overwritten.
FC III ROM Banking
B, followed by a digit between 0 to 3, in the monitor enables the view of the ROMs of the Final Cartridge III. The specified ROM bank will be visible between $8000 and $BFFF. B without a parameter switches the ROM back off.
The following commands in the machine language monitor can be used to dump the complete ROM of an FC3 to disk:
B 0 T 8000 BFFF 8000 S "B0",08,8000,C000 B 1 T 8000 BFFF 8000 S "B1",08,8000,C000 B 2 T 8000 BFFF 8000 S "B2",08,8000,C000 B 3 T 8000 BFFF 8000 S "B3",08,8000,C000