I can confirm that the project is now fully working with either PS/2 or 5pin din connector and works with the VIC20 and the C64!

01/12/21 Ordering is now available!

20/11/21 PCB under review due to incorrect footprint size!

25/11/21 Footprint size now corrected .

Now on my website https://www.levosretrocomputerprojects.co.uk/index.php/c64/c64-vic20-pc-keyboard-adapter

Based on code from https://github.com/Hartland/C64-Keyboard . If you wish to use the arduino IDE full code is here under ps2/c64_keyboard. There are 4 files to download and a library to install . All the details are on that website.

Currently there is no pcb available for this project , so , i decided to create my own.

The circuit decodes the keyboard presses from the PS/2 ( or AT ) keyboard and converts that to matrix connections via the MT8808 matrix chip. As far as the target computer knows it is receiving keystrokes from a genuine matrix keyboard.

The circuit could be adapted for any computer using a matrix keyboard but , i decided to stick with the C64/VIC20 version.

I have also included an LED to show data moving between the keyboard and AVR and the option for an external crystal for the AVR.

Only one keyboard can be connected so you need either a 180degree 5 pin din socket OR a PS/2 6 pin mini din socket .

Currently under test Tested in Australia by Banman ( from the Melon64 forum ) and me in the UK.

If using a PS/2 connector you need to put some kapton tape or nail varnish over this pad to stop any shorts occuring.