MERCIA has a four bit instruction code, as well in the 14 basic instructions as the 16 extended instructions. At this moment there are 28 instructions defined.
May 2016, Jeroen Brinkman
MERCIA in a nutshell
10 bit word
16 bytes I/O memory
496 bytes ROM
512 bytes RAM
Relative addressing
16 function ALU
30 instructions
96*40 bit microcode ROM
9 panels
±2000 relays
>50.000 parts
>100kg
4,5m wide & 1,42m high
Special thanks to:
Aline Brinkman
for the painting of all the woodwork and panels.
Frans den Boer
for his never ending help with PCB designs and mechanics.
Roelof Horst
for his suggestions concerning ALU, architecture and instruction speed.
Rory Mangles
for his RAM design.
Contact me at
Jeroen(at)relaiscomputer.nl