Mapping MIDI CC values?

[Arthur-D]

Hi, I am wanting to map a fader of a Novation Launch Control XL to control my system volume on my Linux system. One thing is that I am not sure how to map it properly to my system volume, but at the very least I could in theory map the bottom state to keyboard.EV_KEY.KEY_VOLUMEDOWN and the top state to keyboard.EV_KEY.KEY_VOLUMEUP. However, I don't know how to map the various CC values that aseqdump shows. midi.md does not come with any example for it, and trying launch.ch8.cc77.0 and launch.ch8.cc77.127 does not work. Is there any way to do that?

[Gremious]

Doesn't seem (?) like they have that, but you can easily do this through their python backend.

Referring to these 2 links should be enough:

#83
https://github.com/cbdevnet/midimonster/blob/master/backends/python.md

But here's also just a config from me:

[backend midi]
name = "Midimonster MIDI (Volume)"
detect = on
; my mixer is called "smc" and this is the "volume.cfg" 
[midi midi_from_smc_volume]
read = 36:1

[python py1]
module = pipewire

[map]
midi_from_smc_volume.ch0.cc46 > py1.pipewire.main

#pipewire.py
import midimonster
import os

def main(value):
    # value is 0...1 so we need to convert it to 0..100
    # making it an int makes it smoother
    value = int(float(value) * 100)
    os.system(f"pactl set-sink-volume 0 {value}%")

    # Or your favorite command e.g.
    # os.system(f'amixer -D pulse sset Master {volume}%')

[Gremious]

As a sidenote, i tried it, and you also can map things to KEY_VOLUMEDOWN and what not in some ways, but if you do a slider.. you're going to hear the system "volume up" sound overlayed 50 million times if you have one.