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Project Notes

#073 QuadNOR

Demonstrates simple cascading NOR gate logic with the 74LS02 and an Arduino

Here’s the quick demo of the circuit in action:

QuadNOR

Notes

See the NOR7402 project readme for more detail on the 74LS02. This is a simple extension of the NOR7402 circuit that cascades 2 NOR gate into 1, with the resulting logic table:

A1 B1 Y1/A3 A2 B2 Y2/B3 Y3
0 0 1 0 0 1 0
0 0 1 0 1 0 0
0 0 1 1 0 0 0
0 0 1 1 1 0 0
0 1 0 0 0 1 0
0 1 0 0 1 0 1
0 1 0 1 0 0 1
0 1 0 1 1 0 1
1 0 0 0 0 1 0
1 0 0 0 1 0 1
1 0 0 1 0 0 1
1 0 0 1 1 0 1
1 1 0 0 0 1 0
1 1 0 0 1 0 1
1 1 0 1 0 0 1
1 1 0 1 1 0 1

Construction

The Breadboard

The Schematic

The Build

Credits and References

About LEAP#73 CMOS/TTLArduino
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This page is a web-friendly rendering of my project notes shared in the LEAP GitHub repository.

LEAP is just my personal collection of projects. Two main themes have emerged in recent years, sometimes combined:

  • electronics - usually involving an Arduino or other microprocessor in one way or another. Some are full-blown projects, while many are trivial breadboard experiments, intended to learn and explore something interesting
  • scale modelling - I caught the bug after deciding to build a Harrier during covid to demonstrate an electronic jet engine simulation. Let the fun begin..
To be honest, I haven't quite figured out if these two interests belong in the same GitHub repo or not. But for now - they are all here!

Projects are often inspired by things found wild on the net, or ideas from the many great electronics and scale modelling podcasts and YouTube channels. Feel free to borrow liberally, and if you spot any issues do let me know (or send a PR!). See the individual projects for credits where due.