This card incorporates the primary input switches at the front of the computer and allows for a program to be loaded into memory (and confirmed) line-by-line. The 8-bit switches are set for each instruction and then deposited into memory.
The card also contains a limited clock, sequencer and controller to operate the appropriate control lines and move the program counter on as necessary.
Below is a list of the blog articles relating to this card (in reverse date order):
27 Mar 2018 - 4 min read
Auxiliary Control Construction
In my last three posts I covered the design of the auxiliary control unit which will ease entering and inspecting programs in the computer’s memory. With the design ‘in the …
07 Feb 2018 - 4 min read
Auxiliary Control Design (Part 3 of 3)
This is the last post in a mini-series of three covering the design of the auxiliary control unit which will ease entering and inspecting programs in the computer’s …
29 Jan 2018 - 12 min read
Auxiliary Control Design (Part 2 of 3)
In my last post I made a start on the auxiliary control design which once completed will make it much easier to load instructions in to memory - effectively it’s a …
24 Jan 2018 - 6 min read
Auxiliary Control Design (Part 1 of 3)
My relay computer is now at the point where it can execute a program in memory without assistance. In order to do that though, of course, the program needs to be loaded into …
08 Apr 2015 - 4 min read
User Interface Design: Instruction, Clock and Sequencer
Over my last seven posts I’ve been slowly putting together the card designs so that the computer will be able to operate the MOV-8, ALU and SETAB instructions. The final …
05 Jul 2014 - 6 min read
Now I’ve got a fully working ALU and four registers completed I want to take a short break from card building and turn my attention to making it easier to interact with …
