Re: [alsa-devel] Re: midi controllers + laptop

Re: [alsa-devel] Re: midi controllers + laptop

[Paul Barton-Davis]

>ALSA folks, would it be possible to redirect the ALSA sequencer
>output to a serial MIDI device ? If yes what are the right
>steps to do this ?

best way: write a kernel module that sets itself up as a client of the
sequencer. The module is simple: it just forwards the data (post
transformation from sequencer events to actual MIDI) on to the real
serial driver for the serial MIDI interface. Its not obvious how to do
this at first sight, but I recall find examples of other "pseudo
drivers" in the kernel that do such forwarding.

easiest way: write a user-space app that registers as a client of the
sequencer and forwards all data (post-transformation from sequencer
events to actual MIDI) to an open file descriptor that results from
opening the serial MIDI device.

'nuff said ?

--p

Re: [alsa-devel] Re: midi controllers + laptop

[Paul Barton-Davis]

>/dev/midi00 behaves like a std serial device except athat it runs 
>always at 31250bps.

not true. /dev/midiNN does not support any (or certainly not most) of
the serial-specific ioctl's that can be used to configure a real
serial port. i've seen some amazing code that attempt to set the
VBREAK character for the MIDI port :) duh ...

also, the buffering of the OSS /dev/midi device is completely
different from that done by the serial driver. its also not very good :)

as ever: use ALSA.

--p