06 Dec 2013 - 1 min read
Following on from my last post I can now test the LEDs that have been soldered and hooked up to the header pins on each of the three ALU cards (Logic, Arithmetic and Control). …
06 Dec 2013 - 1 min read
ALU Construction: Logic Card Wire Links
Before I can test all of the LEDs laid down so far (to make sure they survived the heat of the soldering iron) I need to add some wire links on the logic card between the LED …
05 Dec 2013 - 3 min read
ALU Construction: LED Header Pins
So far, in the construction of the three ALU cards (Logic, Arithmetic and Control) I’ve soldered down the connectors and LEDs. It’s now time to solder in some …
03 Dec 2013 - 4 min read
Backplane Design and Construction
Originally when I was thinking about how I’d connect up the various cards of this computer I had ribbon cables in mind. Ribbon cables are straightforward to use and …
02 Dec 2013 - 4 min read
ALU Construction: Connectors and LEDs
As promised in my last post it’s finally time to get the soldering iron out and make a start on constructing the three cards that make up the ALU. I’m going start …
01 Dec 2013 - 4 min read
In the last three posts I introduced the design for the 3-to-8 Function Decoder, Zero Detect circuit and the Condition Registers. In this post I’ll put all three of …
30 Nov 2013 - 4 min read
ALU Design: Condition Registers
This post covers the design of the ALU Condition Registers which along with the 3-to-8 Function Decoder and Zero Detect circuit (both covered in my previous posts) make up the …
23 Nov 2013 - 2 min read
This post covers the design of the Zero Detect circuit which along with the 3-to-8 Function Decoder (covered in my last post) and the Condition Registers (next post) make up …
20 Nov 2013 - 2 min read
This post covers the design of a 3-to-8 Function Decoder which along with the Zero Detect circuit and Condition Registers will all go in to the ALU Control Card. The Decoder …
17 Nov 2013 - 5 min read
ALU Design: 8-bit Arithmetic Unit
In the last post I introduced the design for the 1-bit Arithmetic Unit. This post covers connecting eight of these units together to make an 8-bit Arithmetic Unit along with …
15 Nov 2013 - 3 min read
ALU Design: 1-bit Arithmetic Unit
This post covers the design of a 1-bit Arithmetic Unit that can add two input bits together (B and C) with carry in and out. Here’s a schematic of the 1-bit Arithmetic …
13 Nov 2013 - 5 min read
In the last post I introduced the design for a 1-bit Logic Unit. This post covers the design effort to cram 8 of these on to a single pad board complete with connectors, …