Hi, I’d like to setup more virtual ports, like the touchosc and midi-through ports, if possible in realtime. I’ve built a nodejs stepsequencer application that sends midi via node-midi and rtmidi to the touchosc or midi-through ports in modep. This just works fine, touchosc and midi-through showed up in the list of available midi ports.
I have 2 questions:
With node-midi you can open virtual ports like this:
const midi = require('midi');
const input = new midi.Input();
input.openVirtualPort("PORT 1");
const output = new midi.Output();
output.openVirtualPort("PORT 1");
But they don’t show up in modep’s list of available midi ports. I tried to connect ports with aconnect x:0 y:0 but this didn’t work, at least the way I did it.
Can someone help me to solve this?
How to setup ports like the midi-through one that you implemented?
The MOD software ignores non-hardware MIDI ports. Fortunately, when creating a new ALSA virtual MIDI port, you may specify the ‘Hardware’ flag, so it shows up in MOD. We’ve wrote a tiny utility just for this purpose called amidithru, it should already be available on your system.
Here’s how touchosc2midi is implemented, so it appears in MOD UI:
In node-midi the virtual ports are recognized as hardware ports and now have to be opened with a port number.
const input = new midi.Input();
input.openPort([PORT_NUMBER]);
I’ll wrap this to nodejs so i can execute amidithru in realtime.
For now, having 8 virtual ports (MIDI 1, MIDI 2, … , MIDI 8) showing up in MOD UI. I was expecting them to be listed in alphabetic order form MIDI 1 to MIDI 8, but in MOD UI they are listed randomly. On boot I’m calling 8 services like /etc/systemd/system/virtual-midi-port-[PORT_NUMBER].service:
[Unit]
Description=amidithru service for virtual midi port
After=sound.target
Wants=sound.target
[Service]
ExecStart=/usr/bin/amidithru 'MIDI [PORT_NUMBER]'
User=patch
Group=patch
Restart=always
RestartSec=2
[Install]
WantedBy=multi-user.target
I wonder if it depends on the order the services are started in. You could try and make service N to depend on service N-1, to keep the order of startup strict.
I think you have to use After= to ensure the other services are fully up before next one is started.
You may try to figure out the logic there, and adapt to it, or try to modify the sorting logic to your needs.
I think you may be able to find host.py somewhere in /usr/ and edit it. Restarting modep-mod-ui service would probably be necessary for changes to take effect.
@Giedrius thanks! Sorting in /usr/lib/python3/dist-packages/mod/host.py only affected the ports list (the one with with the checkboxes). But it pointed to the right api for jack
Sorting hardware ports directly at the source in /usr/lib/python3/dist-packages/modtools/utils.py. Change the get_jack_hardware_ports def to:
def get_jack_hardware_ports(isAudio, isOutput):
port_data = charPtrPtrToStringList(utils.get_jack_hardware_ports(isAudio, isOutput))
sorted = {}
sorting = []
ports = []
for port_id in port_data:
port_alias = get_jack_port_alias(port_id)
sorted[port_alias] = port_id
sorting.append(port_alias)
sorting.sort()
for port_alias in sorting:
ports.append(sorted[port_alias])
return ports
Still have to find a solution for the ajax part after clicking save in the ports list. Not sure from where it gets the ports data for updating the pedalboard gui. Unluckily, not from get_jack_hardware_ports. I’ll post it here.
For now it sorts hardware ports alphabetically on load, both, the graphical input/output ports and the ports list with checkboxes.
