7400 competition entry: 1 bit microcontroller

Check out Giuseppe’sĀ Open 7400 competition entry. It’s a 1 bit microprocessor based on the MC14500 CMOS chip.

This circuit is based on the CMOS chip MC14500. This chip is an ICU (industrial control unit) built from Motorola few years ago, it is a 1 bit processor that can do some logical operations. This chip is now discontinued but can be found on ebay and other sites.
My circuit probably doesn’t have an application in real world, but can be useful for didactic purposes, to learn how a simple microprocessor works.

Build something that uses or abuses a logic chip and get amazing boards, tools, and other swag. The Open 7400 Logic Competition promotes awareness of the basic building blocks of modern circuits. Devious geeks ignited the computer revolution with discrete logic computers, what can you do? Details and entry form here.

Via the forum.

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  1. The greatest calculators ever (HP programmables) used a bit-serial processor that’s basically the same as this. (Same as the old big-iron)

  2. Althroug is not a ‘pure’ 7400 design, I think it’s very helpfull to understand the microcontroller’s architecture

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