05 Nov 2017 - 8 min read
Miscellany Special: Backplane X, Cable Routing and Address Bus
Continuing on with the theme from my last post … here is another ‘miscellany special’ covering all the little ‘side jobs’ I’ve been doing …
29 Oct 2017 - 5 min read
Miscellany Special: Power Distribution
Having somehow forgotten to take time off work I’m now playing ‘annual leave catch up’ which means lots of four day weeks but also, and more importantly for …
17 Sep 2017 - 5 min read
Control Design: Fetch and Increment
The design of the computer’s memory, incrementer and program counter are now complete but there’s one last piece of the ‘puzzle’ required to get the …
06 Sep 2017 - 6 min read
In my last post I started the design for the computer’s memory unit which is spread over two cards. With the lower memory card design in place its now time to finish the …
03 Sep 2017 - 8 min read
In my last post I explained my decision to use a ‘modern’ memory chip in my relay computer … I also alluded to there being some complexities in interfacing …
06 Aug 2017 - 4 min read
I’ve nearly got the design for the memory cards done and ready to share but once that’s out the way it’ll be time to get on with some construction again. …
17 Jul 2017 - 3 min read
In my last post I covered the design of the 16-bit half adder which takes whatever value is currently on the address bus and increments it by one. To make this incremented …
15 Jul 2017 - 2 min read
Incrementer Design: 16-bit Half Adder
In the last post I introduced the design for the 1-bit Half Adder. This post covers connecting sixteen of these units together to make the 16-bit Half Adder. So, diving …
04 Jun 2017 - 3 min read
Incrementer Design: 1-bit Half Adder
Typical isn’t it?! … you wait 10 months for a post and then two come along at once. Well, all being well, this should be the first of a short flurry of posts as I …
29 May 2017 - 6 min read
Register Design: Program Counter
It’s been a while since my last post … pretty much 10 months in fact … and I’d love to say I’ve been quietly working on my relay computer in …
24 Jul 2016 - 2 min read
It’s been a bit quiet on the relay computer front again for a while … well it is summer after all and there’s no point staying inside the house tending to …