From mboxrd@z Thu Jan 1 00:00:00 1970 From: Clemens Ladisch Subject: Re: RawMIDI behaviour with MidiFace 4x4 Date: Mon, 09 Mar 2015 09:47:41 +0100 Message-ID: <54FD5E2D.40801@ladisch.de> References: <6A72E9C91650BD49A6D9B305755BC04C42D801FA@mbs1.ad.jyu.fi> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from dehamd003.servertools24.de (dehamd003.servertools24.de [31.47.254.18]) by alsa0.perex.cz (Postfix) with ESMTP id 024092605A4 for ; Mon, 9 Mar 2015 09:47:44 +0100 (CET) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Ricard Wanderlof Cc: "alsa-devel@alsa-project.org" , "Kalvas, Taneli" List-Id: alsa-devel@alsa-project.org Ricard Wanderlof wrote: > On Sat, 7 Mar 2015, Kalvas, Taneli wrote: >> I am developing a patch librarian for a synthesizer. Because the >> communication happens with Midi sysex and timing is not relevant I chose >> RawMIDI interface and not the alsa sequencer. The problem I have >> encountered is that writing to the midi port with snd_rawmidi_write() >> seems to broken. The function accepts any size of data block and claims >> to have sent everything. In reality only a part of the message is sent. >> For a large block size I can see the activity light blinking for >> fraction of a second. This happens both in blocking and non-blocking >> mode. I would expect the snd_rawmidi_write() to accept only a part of >> the message. > > Can't help with rawmidi, but I can at least report that my experience > using the sequencer interface has been that it is rather straightforward > to use, even if just using it to send and transmit sysex data, even when > the data is longer than 300 bytes. If the data is larger than the RawMIDI buffer size (4096 bytes), the sequencer does not wait (like snd_rawmidi_write() would do), but just drops data. Regards, Clemens