Make Charon act as PS/2 keyboard

[ddrcode]

It's a niche requirement, but a cool one - Charon could act as a PS/2 keyboard and be connected to devices like Commander X16 without a need for any additional keyboard. Also - finally - some idea to use PI's GPIO ports :-)

Resources

• PS2/2 Keyboard on osdev.org - very comprehensive guide of the protocol plus scancodes table
• Ben Eater's video on PS/2 - Ben explains the PS/2 details in context of his breadboard computer
• ps2pi - simple, hacky project demonstrating how to connect PS/2 keyboard to Pi Zero with two resistors and a diode.
• Gat ASCII data from PS/2 keyboards - great, detailed article explaining PS/2 protocol and providing flowchart for ASCII decoding (pasted below, just in case)

ASCII decoding

Source: Gat ASCII data from PS/2 keyboards