building my own relay computer

ben bfranchuk at
Fri Feb 13 19:14:53 CST 2015

On 2/13/2015 6:02 PM, Cory Heisterkamp wrote:
> Tom, any reason for choosing the Harvard architecture?
> I'm currently in the middle of a relay computer build so I'll toss in
> my 2 cents. The most important thing I hit on early is to define the
> instruction set, work out a number of potential applications/uses on
> paper (or excel), and step through each instruction to make sure the
> machine is capable enough. You'll probably discover a number of
> efficiency improvements you can make to the hardware while doing so,
> and a few "hardware subroutines" worth adding. You can also baseline
> how long a program will take to run if you settle on a clock rate,
> and determine if there's a better way to do it.
> Ultimately, relay computers are SLOW. Don't take 6 cycles to do what
> could be accomplished with a couple extra relays and a single pulse.
> Well thought out HW and instructions will pay big dividends when the
> soldering iron comes out. -Cory
The alu has never relay been a problem with relays, but what about main
storage? Punched tape (paper/film/card) is no longer with us for I/O.

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