Yes, this is the correct place to ask. I hope someone knowledgeable about hardware will respond.

Both classic MIDI and USB MIDI have a latency of about one millisecond, so it does not make sense to have a scan interval much shorter than this.

You want to avoid noticeable jitter. Bass pedals are not played very quickly, so you might be able to get away with a longer interval.

[quotePost id=16524]Both classic MIDI and USB MIDI have a latency of about one millisecond, so it does not make sense to have a scan interval much shorter than this.

You want to avoid noticeable jitter. Bass pedals are not played very quickly, so you might be able to get away with a longer interval.[/quotePost]

But isn't the overall latency important as well? The duration from the key press to the detection shouldn't exceed a millisecond or so either.

Yes. But reducing the overall latency from 1.4 ms to 1.2 ms might not be worth the effort.

Thanks for the ideas. Actually I'm seeking for a place for discussing the scanning algorithm (software wise) a bit more in depth.
Do you think I should proceed here? Scanning a musical keyboard might be different from scanning a calculator or computer keyboard.

Especially when considering situations where you play legato and the last note is triggered while the second but last still is pressed.

Asking here is OK.

There's nothing special about legato; only the device that actually generates sounds has to decide whether two notes are near enough to be legato.