I've been doing a bunch of experiments with PD on a Raspberry Pi, with custom-built MIDI control via a Teensy microcontroller. I've been using Raspbian lite with no GUI. This was working really well until recently.

For various reasons I updated my Raspberry Pi to the latest Raspbian (Stretch) which also allowed me to get a slightly more decent build of PD, 0.47.1.

Since doing that I can't seem to get any MIDI input in PD, no matter what startup flags I use. Most tellingly, if I run pd -nogui -listdev I get the following list:
audio input devices:

1. bcm2835 ALSA (hardware)
2. bcm2835 ALSA (plug-in)
3. Teensy MIDI (hardware)
4. Teensy MIDI (plug-in)
   audio output devices:
5. bcm2835 ALSA (hardware)
6. bcm2835 ALSA (plug-in)
7. Teensy MIDI (hardware)
8. Teensy MIDI (plug-in)
   API number 1

no midi input devices found
no midi output devices found

--
I find it very odd that it lists my Teensy MIDI device as an audio input and output, and also says that no midi input or output devices have been found. It is somewhat understandable that my patches will not therefore recognise any midi activity, but I don't understand why PD isn't seeing the MIDI devices.

If I run aconnect -o I can see that the Raspberry Pi recognises the device:
client 14: 'Midi Through' [type=kernel]
0 'Midi Through Port-0'
client 20: 'Teensy MIDI' [type=kernel,card=1]
0 'Teensy MIDI MIDI 1'

and if I run aseqdump -p 20 the MIDI data comes streaming through normally. I'm interpreting this to mean that the MIDI device is working, and the alsamidi system is working on the rPi. My only explanation is that something has changed in PD 0.47.1 to create this bug?

I am thinking about starting from scratch and installing Raspbian Jessie instead to test and see if this works, but I'd like to avoid that if possible! Any ideas?

OK an update!

I installed Raspbian Jessie Lite and Pure Data 0.46 and the MIDI input worked fine. So I figured the problem had to do with the "upgrade" to Stretch and PD 0.47.

HOWEVER then I installed the software for my Pisound audio card, which is what I was using for audio input and output. This requires some sort of kernel update. After that, the MIDI stopped working again! So I'm now wondering if the problem is something to do with that kernel update. This means that Raspbian Stretch and PD 0.47 may actually be fine, but it was my Pisound software messing everything up...

Hi,

Did you ever find a solution to this? I am on Pd .49 and a Raspberry Pi 3. I can't get Pd do see my midi controller at all.

thanks, Nick

Same issue here. Even with Pd 0.49. Any midi device I connect, appears as an audio device in the Pd settings.

I did end up finding a solution for this that mostly works, via the Pisound forums. It should work without a Pisound too: https://community.blokas.io/t/script-for-launching-pd-patch-with-midi-without-aconnect/1010/3?u=amazingrolo

Essentially they've made a script that automatically connects all of the available midi ports to each other. It worked for me.

No one seems to be able to answer my questions on any forums as regards to why this happened. I still don't know what changed between Raspbian Jessie and Raspian (or PD 0.46 and 0.47) that made this significantly more of a pain to set up. The forums are full of people running into this problem!

@amazingrolo Thanks for this update. Yes it's an annoying problem for sure. I made some really convoluted python script that takes 30 seconds to connect my midi devices and pd. Not very ideal in a live performance setting.

I did see in the pd facebook group that someone posted what sounds like a great Rpi disc image with a real time kernal. I haven't tried it out yet, but it sounds promising. Here's the link if anyone is interested:

https://blokas.io/patchbox-os/?fbclid=IwAR0bnDB-rkzJPeWAev8FF4Wjf646fzF0weJH1Pb733AJ7avImPJ7Z9sMKdA

when I get to it I'll let you know if the there's problems with connecting midi devices.

I'd forgotten about Patchbox...I just gave it a try and it seems to work well. It has the auto midi connecting built-in, so my startup script doesn't need to include that.

I haven't noticed much of a difference in terms of audio performance, but even just the auto midi connection stuff makes it worth it!

@amazingrolo Wow that's great to know! thanks for checking that out.