Hi!
I once had the same setup. I just enable the general MPU401 MIDI driver in
ALSA and that was that. I just attached the right cable (gameport to MIDI i/o)
and all worked as well as could be expected.
With alsa you could try aconnect -li and aconnect -lo to see ALSA sequencer
MIDI ports offered by your soundcard. Perhaps they're already there.
You could try this to test (having figured out the number of your midi
port).
aplaymidi -p 16:0 test.mid
The 16 would be the port number (client number) gotten from aconnect the :0
says use the first port of that client (which is some kind of standard or
default). If you have a MIDI keyboard connected, which can play back MIDI from
MIDI-in, you'll see if it works.
About rosegarden, I don't know. But I think it still works with ALSA
sequencer MIDI system, so no need, to dabble with JACK MIDI right from the
start.
Kindest regards
Julien
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