Showing posts from September, 2014

Sequencing & Control Design: Overview

I've now got my computer to a state where I can perform ALU operations and push values around the four registers by manually operating the various control lines. It's time to move things on a bit now and work towards getting the computer to the point where given a specific instruction/op-code it can operate the control lines itself without further input from the user. Eventually the computer will be given a list of instructions to perform which it'll work through step by step but for now the next milestone is to automate the operation of a single instruction.

In my recent videos I've been demonstrating, by hand, the processing of a simple arithmetic sequence on the computer by following a list of instructions represented as a set of mnemonics. Here's a screenshot from the video showing the full set of mnemonics/instructions to perform the calculation of (((2 + 4 + 1) x 3) - 3):
Here's a description of the mnemonics used in this calculation:
LDI r,v
Load Immediat…