building my own relay computer

[Brent Hilpert]

On 2015-Feb-13, at 2:56 PM, Tom Sparks wrote:
> On 14/02/15 08:20, Brent Hilpert wrote:
>> On 2015-Feb-13, at 1:40 PM, Tom Sparks wrote:
>> 
>>> I've been bouncing around the idea of building my own relay computer
>>> 
>>> * I have mostly inspired by the TIM project[1] and Harry Porter's Relay
>>> Computer[2]
>>> * I am looking at having a limited number registers like the 6502 or 6800
>>> * the computer is going to be Harvard architecture based
>>> 
>>> I wondering have any of use done anything like this?
>>> 
>>> [1] http://www.northdownfarm.co.uk/rory/tim/
>>> [2] http://web.cecs.pdx.edu/~harry/Relay/
>> 
>> 
>> I've examined and written about (and done some limited implementation of) Simon, which is Harvard architecture.
>> 	 http://www.cs.ubc.ca/~hilpert/e/simon/index.html
> that website looks familiar, thats it, the memory core write up
> bookmarked and added to my wget queue :)
> 
>> 
>> Due to it's limitations I haven't been all that enthused about fully constructing it however.
>> It could perhaps be expanded into something more interesting.
>> 
>> There's another relay computer design and implementation here which looks interesting:
>> 	http://www.electronixandmore.com/projects/relaycomputertwo/index.html
>> 
> I did bookmark and download electronixandmore website


Just an opinion, but the Zusie / Z3 recreation ref'd by Pontus looks most interesting, if one wants to do an historical design vs. something novel.
The Zusie site mentions the Z3 recreation in Germany.
With a few recreations of the same machine there's the potential to benefit from community software development.

The Zusie fellow sure was fortunate to obtain a large quantity of good relays at scrap prices.
I've long been interested in building a relay computer but that's one of the stumbling blocks - relays new are so pricey today.
Had in mind a physical implementation much like the Zusie, upright front-access 19" relay rack with an LED per relay to show state (and many blinkenlights).