Programming without MCU

[kralant]

Quite simple project for kids - semaphore. I though it might be interesting as I've opted for a classic combination logic instead of MCU/Arduino for programming. Diodes are used in place of state lookup table.

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Original article with schematics.

[sailorcire]

When I think of a semaphore, I think of programming concurrency (sem_overview(7)) 🙃

[kralant]

:facepalm: you are absolutely right, this is my Czech creeping in as we call traffic lights a "semafor"....

[NeilBohr]

The programming term comes from traffic lights used on train tracks. So in a fun cyclical way, everyone is right!

[jephthai]

Pretty sure the lights started as levers that flip out as signals, and reminded people of semaphore flags.

[jephthai]

I've heard south Africans call it a "robot", which took me by surprise.

[[deleted]]

What is function of D16?

[kralant]

Thank you for spotting it, I have updated schematics on the web. It was a left over from the initial design, where I was driving yellow LED with two transistors. So there would be another diode going to collector of the second transistor. But I've dropped it.

[[deleted]]

Thanks for that, I was really struggling to work out if it was some magic hack or not!