On 04/20/2014 03:49 AM, Ralf Mardorf wrote:
IIUC we are not talking about the same alsarawmidi.
On Sat, 2014-04-19 at 18:18 +0200, Ralf Mardorf wrote:
> jackd --sync -Xalsarawmidi -dalsa
-r$sample_rate -p$frames_period
^^^^^ ^^^^^^^^^^^^^
On Sat, 2014-04-19 at 19:47 +0200, Robin Gareus wrote:
> > jackd -S -dalsa -dhw:2 -r48000 -p64 -n2 -Xraw
^^^^^^
^^^^^
it prints
JackALSARawMidiDriver::Start - Starting 'alsarawmidi' driver.
JackALSARawMidiDriver::Start - starting ALSA thread ...
JackALSARawMidiDriver::Start - started ALSA thread.
as part of the startup message.
-Xraw is needed because otherwise I don't get any midi ports at all.
fPlaybackChannels and fCaptureChannels in
<jack2-source>/linux/alsarawmidi/JackALSARawMidiDriver.cpp are zero
otherwise.
Devin wrote:
when I requested MIDI latency/jitter test results for
the driver, I saw peak jitter results as low as 60 microseconds.
The jitter measurement here using alsarawmidi is 100 us stddev over 10K
events, 3 bytes each (using a USB2 device - details in prev email).
That's not far off from what Devin quoted, but without knowing what and
how he measured it, I can't comment on it.
ciao,
robin