Connect a MIDI input to a track with LUA

Getting Stuff Done How do I .... ?
#1

I have a flaky USB-MIDI interface that occasionally needs to be reset. I’m trying to write a LUA script to do this. I’ve got something that resets the audio interface (just stops and starts it), but I’m stuck trying to figure out to connect a physical MIDI device to a track. More specifically, I’m stuck trying to get a list of physical input MIDI devices. I’ve got this, but it prints just about everything except what I’m looking for (the physical MIDI device):

ardour {
  ["type"]    = "EditorAction",
  name        = "Reset MIDI",
  category    = "Utility",
  author      = "Brent Baccala",
  description = "Reset my MIDI interface"
}

function factory (unused_params)
  return function ()
    local engine = Session:engine();
    engine:stop();
    engine:start();
    _, t = engine:get_ports (ARDOUR.DataType.midi (), ARDOUR.PortList ());
    for p in t[2]:iter() do
	local midiport = p:to_midiport ()
        print(midiport:name())
    end
  end
end
#2

For physical (device provided) ports, you need engine::get_backend_ports (...).

The following script may provide some inspiration:

#3

Robin, that did it!

Thank you as always for your prompt reply!

It does seem that I need to specify ARDOUR.PortFlags.IsOutput to get an input port, but I’ll try to investigate that some more. My code is about nine months old, so I don’t have any recent patches.

1 Like
#4

We inherited those constants from JACK and should have replaced them with less ambiguous ones.

It depends on the view-point. From Ardour’s point of view, and output port is a source. Data is provided to Ardour by an output from somewhere (usually hardware).

Likewise an input is a sink, that Ardour sends data to for some other app or hardware to read.

–

This is reversed if you look on the whole system from the outside…