The Logic Unit is one of the three cards making up the broader Artihmetic Logic Unit (ALU).
This card handles 8-bit binary logic operations (AND, OR, XOR of the inputs from register B and C) and 8-bit unary logic operations (NOT and SHL of the inputs from register B). In all cases the output from this card can then be loaded into register A or D.
Below is a list of the blog articles relating to this card (in reverse date order):
18 Dec 2013 - 2 min read
ALU Construction: Completed Logic Card Full Test
The ALU logic card is now finally complete! … well, it is now I’ve popped the last few relays into their sockets. The final card looks like this: As the old …
18 Dec 2013 - 1 min read
ALU Construction: Logic Card Wire Wrap 3
I’m now just one session of wire wrapping away from a completed ALU logic card. The final job is to wire up the gating relays that select one of the five logic results …
12 Dec 2013 - 2 min read
ALU Construction: 8-bit Logic Unit Tests
There’s now enough sockets, solder and wires to test all eight bits of the ALU logic card. This isn’t quite a full test as the gating relays that apply one of the …
12 Dec 2013 - 1 min read
ALU Construction: Logic Card Wire Wrap 2
Continuing on with the wire wrapping for the ALU logic card next up is the input and result links: Given the limited range of colours I’ve got to choose from (Black, …
12 Dec 2013 - 1 min read
ALU Construction: Logic Card Wire Wrap 1
Finally, with all the soldering now done, it’s time to set about wire wrapping the ALU logic card. First up is the internal connections within each logic bit: After wire …
10 Dec 2013 - 2 min read
ALU Construction: Logic Card Power Rails
It seems that every time I move on to the next stage of construction on the ALU logic card it’s fiddlier than the stage before it … this stage is no exception. …
09 Dec 2013 - 2 min read
ALU Construction: Logic Card Relay Sockets
The construction of the ALU logic card is coming along nicely but there’s still a lot of soldering ahead to get all the relay sockets down … and this part is the …
08 Dec 2013 - 1 min read
ALU Construction: Logic Card Header Pins
Following on from the successful construction of the first bit on the ALU logic card in my last post it’s now time to start putting together the other 7 bits and the …
07 Dec 2013 - 2 min read
ALU Construction: 1-bit Logic Full Construction
So, although I probably should construct the logic card methodically a full stage at a time (solder header pins then sockets then wire wrap) I can’t resist fully …
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). …
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 …
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 …
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, …
11 Nov 2013 - 5 min read
This post covers the design of a 1-bit Logic Unit that can produce AND, OR, XOR, NOT and SHL (Shift Left) outputs from two input bits B and C. Here’s a schematic of the …
