This is such a great idea. Is there any way of implementing this so it runs internally without the external wires? Or perhaps even a custom PCB that controls these functions via the cartridge port itself?
U64-MacroCart (for Ultimate 64)
A simple USB macro keyboard shaped like a C64 cartridge for use with the Ultimate 64. (Firmware included)
5
77
0
812
updated
March 7, 2026
Makes
Comments
@homerghost_1420911 This one is originally designed for the first editions of the U64 that didn't have the internal header for additional buttons. Controlling it via the cartridge port itself isn't technically possible.
If you own a newer board with the onboard header you could wire the buttons from this design directly to the pins and skip the Arduino. (you'll only be able to reset, freeze and enter menu).
I do have an idea how to hide the cables internally, but this will require a redesign and that's something I planned to do in the coming weeks. I'll probably post about it in the Ultimate 64 User group on Facebook.
@iinnrr I would be very keen for this! Three buttons and internal routing would be fantastic. I have the U64-II and am currently using cheap buttons on the header but they're a little ugly. This would make for a great experience. (edited)