I’m releasing the first version of the Potmux add-on board for the Keyman64.

The Potmux is a small hardware add-on for the C64 that allows the user to optionally route the control port potentiometer lines to a destination other than the SID.

It is mainly intended to be used with the Keyman64 for the purpose of mapping additional joystick buttons connected to the potentiometer lines to user defined keystrokes.

The potmux utility provided on this page can be used to prefix an existing C64 program with a specific potmux configuration for the Keyman64. The resulting program will first configure the Keyman64 using its serial interface connected to the tapeport lines “Cassette Sense” and “Cassette Write” and then run the original program.

Documentation is available in both english and german.