Commodore Miscellaneous Hardware
Beyond computers, drives and printers, Commodore produced a long tail of accessories and oddities that are now collectable in their own right.
One of the earliest is the CHESSmate of 1978. After buying MOS Technology, Commodore hired the Toronto programmer Peter Jennings, author of the MicroChess program for MOS's KIM-1 board, to turn it into a consumer product. The result was a compact chess computer that is essentially a pared-down KIM-1 with a 6504 processor and Jennings's program in ROM. Its working name was Bobby, and Commodore showed it at the 1979 Summer Consumer Electronics Show.
Another curiosity is the CP/M cartridge for the Commodore 64 from 1983. It contains a 3 MHz Z80 processor that runs CP/M 2.2, passing screen, keyboard and disk work back to the 64's own processor. It failed in the market because the 1541 drive could not read the disk formats most CP/M software was distributed on. Commodore learned the lesson, and the C128 of 1985 had a Z80 built in and a disk drive able to read those formats.
The VIC-20 era produced smaller items such as the VIC-1310 light pen, RS-232 interface modules for the user port, and a cartridge expansion box. The Commodore 64's REU memory units came with a stronger power supply because the original one struggled with the extra load. The Amiga years added internal SCSI controllers such as the A2091 and A4091, the A590 hard drive for the A500, the A2286 PC emulation bridge card and the A2320 display enhancer, while the CD32 got a keyboard and mouse in its own colours. Commodore Australia even sold a combined stereo, tape and photo unit.
Small accessories like these were often thrown away, so complete boxed examples are surprisingly scarce.