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Model 74181: P Outputs

A project log for Homebrew Machine 2

An 8 bit breadboard computer based on the Malvino SAP-2.

brandon-reinhartBrandon Reinhart 07/21/2019 at 05:522 Comments

Two days ago I completed the propagator P output for the model 74181. It looked like a complete mess.

The circuit was functional, but didn't really serve the purpose of making that functionality transparent. I mean, there's a laundry list of bad things going on here.

This didn't meet my standard. I ripped everything out and reworked the circuit.

Here is the current state of the model:

The input switches are more clearly separated. These DIPS do not want to stay in the breadboard, though, so I ordered a different kind to see if I can get better results.

The organization of the logic is as follows:

I'm pretty happy with the progress so far and I've now hooked up this logic enough times that I understand it well.

The next task will be to wire up the generate bits!

Discussions

Dave's Dev Lab wrote 07/21/2019 at 19:59 point

fantastic looking build!

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Brandon Reinhart wrote 07/21/2019 at 23:41 point

Thanks!

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