MIDI messages getting lost, stuck notes

[jedgarpark]

I am still getting stuck notes when NoteOff messages get missed. with this example https://github.com/adafruit/Adafruit_CircuitPython_USB_Host_MIDI/blob/main/examples/usb_host_midi_simpletest_rp2040usbfeather.py if i play three or four note chords rapidly one or more NoteOff messages seems to be missed.

[tannewt]

What devices are you using?

[jedgarpark]

I've tested with two different MIDI keyboards- Arturia Keystep and Akai MPK Mini plugged into the Feather RP2040 USB Host. Output to a couple of different MIDI synths over UART, the 1010music nanobox fireball and the KORG NTS-1.
I've also tested by sending the MIDI out over USB to my Mac and watched the messages with MIDI Monitor as well as playing software synths VCV Rack, Helm, and Vital.

[FoamyGuy]

This is worth testing with the timeout change from #9

I found that without a timeout the midi.receive() call is blocking and leads to events getting stacked up in an internal buffer and delayed until more events come in.

With a timeout the input buffer has a change to "unwind" the events still in it when there are no more events coming in. I don't have any UART midi devices though, all of my testing was with a synthio example more like the other simpletest. I suspect the same situation could occur in the feather USB host UART pass thru example as well.