A simple adaptor that allows the use of a PS2 keyboard with the Victor HC-90 and HC-95 MSX computers
This adaptor is completely based on the work by Kuni, who has graciously shared it at: https://github.com/kuninet/KZ80-PS2KBD
It only requires an Atmega328P chip, a PS2 female connector, a 20 pin female IDC flat cable and a piece of protoboard
1.- The Atmega 328P needs to be flashed with a bootloader that enables it to use the internal oscilator ar 8MHz. Some instructions are here:
https://www.arduino.cc/en/Tutorial/BuiltInExamples/ArduinoToBreadboard
2.- Then, download and install the code from Kuni's repository and upload it to the Atmega using the arduino IDE:
https://github.com/kuninet/KZ80-PS2KBD/tree/master/source/PS2_KZ80
3.- Carefully solder the Atmega to the flat cable and the PS2 connector using the protoboard to hold it together. Connect everything as shown here:
https://github.com/dproldan/HC90_PS2_Keyb/blob/main/hc90%20to%20ps2.png
The connector is shown in the drawing as you would see it from the back of the computer.
Connect everything and good luck!