This page was last updated on Tuesday, May 1, 2012.
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if you have any complaints, comments, suggestions or large donations to make.
Status: I built it using 7400 series chips, and I'm pretty sure it worked.
Cost: Unknown - at a rough estimate, £4.00
Function: Okay, the whole idea is that you input two 4-bit binary numbers (the G inputs and the Q inputs) and the circuit compares the two. (Please note: the wires represent standard binary, with 4 as the highest value digit, so Q4=8, Q3=4, Q2=2 & Q1=1.) The Stop! input can probably be left out - I needed it myself. Here's a kind of 'output truth table' to help you see what the circuit is actually telling you:
| On/Off | Up/Down | What it means |
|---|---|---|
| 0 | X | The numbers are identical |
| 1 | 0 | The Q number is larger |
| 1 | 1 | The Q number is smaller |
Future: Well, I'd like to make it modular, as in, you can repeat the pattern ad infinitum - currently an extra AND gate must be added for every extra bit, if you see what I mean. So there will definitely be a Mark II.
This page was last updated on Tuesday, May 1, 2012.
Contact me at if you have any complaints, comments, suggestions or large donations to make.