Raw midi to Timidity on RPi

[hitsware]

I have Timidity on RPi 3 B
I would like to send raw midi from Ruby
to Timidity.
I.E. 2 or 3 byte midi-messages
I have had success using 'system'
calls to Alsa🙁 c note on-off )

system"amidi -p hw:1,0 -S'90 3C 7F'"
system"amidi -p hw:1,0 -S'B0 7B 0'"

But for some reason the amidi is very (too) slow.
The Timidity sheet mentions an address of:

/dev/snd/midiC1D0

I've been trying :

f=File.open"/dev/snd/midiC1D0","w"
f.write "90 3C 7F"
f.write "B0 7B 0"
end

But no sound 🙁
Any insights greatly appreciated .....

 

[phofman]

I think you are supposed to use the alsa-lib rawmidi funtions, e.g. git.alsa-project.org Git - alsa-lib.git/blob - test/rawmidi.c

In ruby e.g. GitHub - arirusso/alsa-rawmidi: Realtime MIDI IO with Ruby for Linux ?

 

[hitsware]

Thank You,
If it takes that much complication I'll forget it.
It is so simple in Windows with Basic........

 

[phofman]

Well, using that ready-made ruby library seems pretty simple to me...

 

[hitsware]

Well, using that ready-made ruby library seems pretty simple to me...

Not to me .....
It seems to me this should work:

f=File.open"/dev/snd/midiC1D0","w"
f.write "90 3C 7F"
f.write "B0 7B 0"
end

But then I'm old and old fashioned 🙂
Maybe I'll try DosBox

 

[phofman]

Hm, I do not see much difference from the output.rb example:

AlsaRawMIDI::Output.first.open do |output|
...
        output.puts(0x90, note + oct, 100) # note on
        sleep(duration)				     # wait
        output.puts(0x80, note + oct, 100) # note off
        sleep(duration)
...

In alsa the device files perform many functions, that is why you cannot just copy data to them (unlike e.g. the /dev/dsp files of OSS). You have to use appropriate fnctl system calls. That is what the alsa-lib does in snd_rawmidi_open and snd_rawmidi_write API calls and those that alsa-ruby library wraps to provide simple access in ruby.

But do whatever you wish, your fight.

 

[hitsware]

Yes. not bad ......... Thank You
What does one need to do to set up to run that ?

 

[phofman]

Did you actually look at that github readme?

I assume you are a ruby programmer if you asked specifically about ruby. I am not.

 

[hitsware]

Did you actually look at that github readme?

I assume you are a ruby programmer if you asked specifically about ruby. I am not.

I looked but it's beyond me.
I only mentioned Ruby because I use Sonic-Pi which uses it.
BASIC is the only language I'm at all familiar with.

 

[phofman]

Well, I am afraid you will have to learn another language if you want to play with alsa on linux RPi. E.g. python is pretty simple to start with and of course there is a python-midi library GitHub - vishnubob/python-midi: Python MIDI library. Or ruby, java, etc.