Relay Computer

My journey in constructing an 8 bit relay computer from scratch ... made from of a ton of solder, wires, lights, relays, sweat, tears, swearing and money.

ALU Construction: Logic Card Wire Wrap 3

18 Dec 2013     construction , ALU

I’m now just one session of wire wrapping away from a completed ALU logic card. The final job is to wire up the gating relays that select one of the five logic results back on to the data bus. Nothing too difficult … just a case of routing the wires in the best way possible to keep things neat and out of the way of the relay sockets.

ALU Logic Card ALU Logic Card (close up 1) ALU Logic Card (close up 2)

Keeping with the same wiring colour convention as before the green wires are the results heading out to the data bus, the blue wires are the inputs B and C and the yellow wires are the control lines which activate each of the gating relays as required.

That’s the logic card pretty much done … just need to pop in the final relays and give everything a test.