Missing MIDI IN

I’ve had a missing MIDI IN port for some time now althou’ I get MIDI Thru lights.

Does anyone know what the following might mean?

uart0_pclk not registered
uart0_pclk alias not registered

“MIDI Thru” is completely hardware, aka, it will work without SD card in your RBPi :wink:

MIDI-IN is implemented with “ttymidi”, reading raw MIDI data from the RBPi’s UART and flowing jack-MIDI data as a Jack port.

  • Could you check if “ttymidi” is running?

    systemctl status mod-ttymidi
  • You could also try to get the ttymidi logs with:

    journalctl -u mod-ttymidi


I have had several incidents of ttymidi becoming inoperable since I updated to Aruk RC1. ttymidi is still running and jack_lsp -c shows that JACK knows about the port and that it is not routed. Attempting to route it with jack_connect ttymidi:MIDI_in ZynMidiRouter:main_in gives the error cannot connect client, already connected?. If I restart the RPi or restart the service with systemctl restart mod-ttymidi then it starts to work again for some minutes but will fail after a while.