keyboard MERA-REFA KL-13

DC +5V 0.28A K2 Z4 ll N
ZN-87/REFA-095
NR 00346
MADE IN POLAND

Klawiatura MERA-REFA KL-13
Mazovia 1016, Polish PC XT

protocol analysing

Attach  keyboard data (pin 2) to arduino pin 2
Attach  keyboard clock(pin 3) to arduino pin 3
Attach  keyboard vcc (pin 5) to arduino pin +5v
Attach  keyboard gnd (pin 4) to arduino pin gnd

 https://github.com/DenisSouth/log_analyzer
 two_channel.ino

keyboard.ino - driver with terminal output