Hello,

On Thu, Mar 13, 2008 at 9:34 AM, Jaroslav Kysela perex@perex.cz wrote:

On Thu, 13 Mar 2008, ki.ber.kom.uni.st wrote:

...

i was happy user of PySeq [1] and it was easy to send directly 'noteon' event.. more or less in python interactoin session: import pyseq

seq = pyseq.PySeq() seq.createOutPort() event = snd_seq_event() event.setSource(0) event.setSubscribers() event.setNoteOn(ch, note, velocity) event.sendAsIs(seq)

it seems that pyalsa will go along alsa development so i tried pyalsa.. but....

You can send NOTEON events without a queue, but you cannot send NOTE events without a queue. (subtle difference: note_ON_)

The following code will work; 14:0 is "midi-through" in my system... I run aseqdump -p 14:0 on another window:

seq = alsaseq.Sequencer() event = alsaseq.SeqEvent(alsaseq.SEQ_EVENT_NOTEON) event.set_data({'note.note' : 0x40, 'note.velocity' : 64}) event.dest = (14, 0) seq.output_event(event) seq.drain_output()

...

i tried this: from pyalsa import alsaseq seq = alsaseq.Sequencer() seq.create_simple_port("myPort", alsaseq.SEQ_PORT_TYPE_APPLICATION, alsaseq.SEQ_PORT_CAP_SUBS_READ | alsaseq.SEQ_PORT_CAP_READ | alsaseq.SEQ_PORT_CAP_WRITE | alsaseq.SEQ_PORT_CAP_SUBS_WRITE)

AFAIK, You don't need a port if you are sending events directly. Now, if you subscribe and connect ports, you don't need to assign them into the event, because a new event is created with snd_seq_ev_set_subs called..

You can check this and other stuff with the following code:

-ini------------- def _find_attributes(typelist): l = [] for t in typelist: d = t.__dict__.items() for k, v in d: v = "%s" % v if v.startswith("<attribute"): l.append(k) l.sort() return l

def dump_event(port, name = 'seqevent'): print "Dumping Event ---------->" print "%s" % port l = _find_attributes([alsaseq.SeqEvent]) for k in l: print "%-30.30s %s" % (name + "." + k, port.__getattribute__(k)) return

seq = alsaseq.Sequencer() event = alsaseq.SeqEvent(alsaseq.SEQ_EVENT_NOTEON) event.set_data({'note.note' : 0x40, 'note.velocity' : 64}) dump_event(event) seq.output_event(event) seq.drain_output() -------------end--

...

event = alsaseq.SeqEvent(alsaseq.SEQ_EVENT_NOTE) event.set_data({'note.note' : 0x40, 'note.velocity' : 127, 'note.duration' : 1, 'note.off_velocity' : 0})

note.duration and note.off_velocity make sense only for SEQ_EVENT_NOTE, but you need a queue... so, use SEQ_EVENT_NOTEON and SEQ_EVENT_NOTEOFF instead....

I'm planning to move event.set_data() to attributes, like event.note_note, event.note_velocity ... Tell me what you think!

...

event.dest = (20, 0) seq.output_event(event) seq.drain_output()

after drain it says: "SequencerError: Failed to drain output: Invalid argument"

Well, that's what asoundlib says... weird, don't you think?

Alsa hackers: This is a good proof that alsa-lib message errors really, really sucks... Is there any chance to change this? I mean, if I volunteer to improve this could be accepted? Any hints for doing this?

[...]

...

any ideas? do i have to use queues to be able to send 'noteon'.. for my purposes it seems to me that that's overkill....

Remember: python is far away of real-time so if you get weirds timings you may reconsider using a queue anyway!

HTH,