2019-01-26 Board ordered. Project documentation uploaded.
The keyboard connector is 5-pin DIN for the XT.
I don't want to pay 55 quid for a genuine XT keyboard, which would take up scarce space here.
I will need an adapter like this one:
2019-01-31 The PIC12F629 chips for the keyboard converter arrived today.
2019-02-05 The board arrived today. PCB date code is 1987-12-04. Looks like four layers.
Keyboard converter chips programmed today.
BIOS ROM almost identical to Arcom BIOS ROM, but with the company name changed.
Boot ROM has less than 256 bytes of code in a 16K chip.