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by doix 1350 days ago
Okay, I can kind of see how it makes a difference for n-key rollover.

> The switching time is like 20-50ns on these parts, so while it's not quite as fast as a GPIO register read, it's still pretty quick, more than fast enough for keyboards.

I guess my point was that if you change which input you're reading from the mux and then immediately sample with the MCU, you'll get unstable data. 50ns is 20MHz, I can easily see an MCU used in a keyboard being fast enough to hit this.

It's obviously easy to work around, but so is ghosting.