09 Aug 2019 - 9 min read
It’s time for the oddly therapeutic part of designing a PCB … laying out the board. In my last post I covered the schematic design and so we now have all the …
15 Jul 2019 - 8 min read
In my last couple of posts I’ve been building up to a change of approach in how I’m making the cards in my computer. This is mainly because I can’t face the …
11 Nov 2017 - 3 min read
In my last couple of posts I’ve been slightly distracted by some ‘miscellany’ but now I return to form and crack on with constructing the program counter. …
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 …
16 May 2015 - 1 min read
Register Construction: Completed Instruction Register Full Test
Following on from my last post, and after popping in some relays, the instruction register is complete and looks like this: As usual I’ve put a video together that …
09 May 2015 - 3 min read
Register Construction: Instruction Register
There’s been lots of theory going on in my recent posts but the time for design is over (for now) … it’s time to get constructing. The first card up in this …
01 Dec 2014 - 6 min read
Register Design: Instruction Register
Well, it’s fair to say that I rather underestimated just how much time decorating the new house would take up … and that’s mainly because …
19 Aug 2014 - 2 min read
ALU & Registers A-D Test with new Display Cards
Now that the two display cards are complete enough to display and control the status of the ALU and four registers (A-D) it’s time to fit them to the upper enclosure. …
28 Jun 2014 - 2 min read
Register Construction: Completed A and D 8-bit Registers Full Test
The A/D Register card is now complete and looks like this: As usual I’ve put a video together that demonstrates this card in operation. This time I don’t show …
22 Jun 2014 - 3 min read
Register Construction: A and D 8-bit Registers
I haven’t posted in nearly a month but in between bouts of enjoying the rare British sunshine I’ve been plodding away at the A/D register card and it’s now …
26 May 2014 - 2 min read
Register Construction: Completed B and C 8-bit Registers Full Test
The B/C Register card is now complete and looks like this: As usual I’ve put a video together which demonstrates this card in operation … firstly on its own but …
24 May 2014 - 4 min read
Register Construction: B and C 8-bit Registers
As mentioned in my last post I decided this time around not to post after each stage of card construction (being as the construction steps are now pretty similar to those for …
11 May 2014 - 6 min read
Register Design: B and C 8-bit Registers
In a recent post I put up the design for the A and D 8-bit register card … the B and C register card is very similar in design but has the additional complexity that it …
24 Apr 2014 - 5 min read
Register Design: Dual Output 8-bit Register
In the last post I introduced the design for the A/D register card (which as its name suggests contains the A and D 8-bit registers). I’m now making a start on the …
20 Apr 2014 - 5 min read
Register Design: A and D 8-bit Registers
In the last post I introduced the design for a general purpose 8-bit register. This post covers taking two of those registers along with status LEDs and gating relays to …
16 Apr 2014 - 4 min read
Register Design: General Purpose 8-bit Register
This post covers the design of a general purpose 8-bit register that can be loaded from the data bus and then selected back to the data bus at a later time. This permits …