So how does a PS/2 keyboard interface work?

Ben Eater · 570.4K views · 2021-03-06 · 33:07

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Overview

Ben Eater explains how the PS/2 keyboard interface works, covering its clocked serial protocol and scancodes. He builds up the hardware-level understanding needed to read keypresses.

On Hacker News

HN commenters point to it as the clearest explanation of the PS/2 protocol, usually when keyboard interfaces come up.

Recommended by 1 HN people across 1 months · HN mentions 2021–2021

Topics

Electronics & circuit design Embedded systems & DIY electronics

What people said

zackbloom · 2021-04 · Recommendation
There's a good video on how PS/2 works here: [VIDEO] It's pretty straight-forward. There are also pre-made kits for digitizing typewriters if that interests you.
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RJIb8RBYxzAMX9u · 2021-10 · Reference
I'd imagine it would be very difficult, and would require a relatively powerful MCU. Ben Eater's made a few videos discussing how PS/2[0] and USB keyboards[1] work. USB's a vastly more complicated protocol compared to PS/2. [0] [VIDEO] [1] [LINK]
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bear8642 · 2021-09 · Reference
think might be at end of this one < [VIDEO] > though there's a few he's done recently on USB spec
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Sources

Video by Ben Eater, played through YouTube.

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