Fredrik Andersson has built a microprogrammable CPU from 1500 relays salvaged from telephone exhange boards, inspired by Konrad Zuse

Collection of short videos:


Features:

8-bit data bus and 16-bit address bus
3 x 8-bit accumulator registers, 2 x 12-bit registers (for index, addresses and jumps)
64k solid state memory, holding heap, stack and program
12-bit program counter and 12-bit stack pointer
ALU capable of not, and, or, xor, add, increment, decrement, shift, and indirectly, subtraction
Writable microprogram stored in solid-state device for sequencing

Via David Galloway

Here's his thread on a Swedish forum where you can follow his progress http://elektronikforumet.com/forum/view ... =3&t=44171

Thanks!

I see there a pointer to the rebuild project of Zuse's Z3 - mostly in German. 500 relays?

Architecture: