From mboxrd@z Thu Jan 1 00:00:00 1970 From: "John Matthews" Subject: Via 82xx drivers Date: Thu, 9 Sep 2004 12:11:40 +0100 Sender: alsa-devel-admin@lists.sourceforge.net Message-ID: <003501c4965d$c8647c10$c400a8c0@imspc02> Mime-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0032_01C49666.29D4D0A0" Return-path: Errors-To: alsa-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: alsa-devel@lists.sourceforge.net List-Id: alsa-devel@alsa-project.org This is a multi-part message in MIME format. ------=_NextPart_000_0032_01C49666.29D4D0A0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hi, I'm trying to develop a complete system / distribution using the via = "mini-itx" platform. The idea is that we take in sensor positions from = analog sensors and output sounds based on the position of these sensors. = This setup is used for music therapy, with disabled children producing = music using, for example, ultrasonic position sensors (amongst other = types of sensor). I've written some code to accept input from the alsa = sequencer and act as a midi router, and I'm using fluidsynth as an = output synthesiser. The mini-itx board is a very small form factor fully integrated pc = motherboard with a via c3 processor. The sound controller on this = board is part of a via 8235 southbridge. The snd-via82xx alsa module works fine on this board, apart from the = fact that it is very, very noisy - unusably so. There is a background = drone and whenever the processor does something you get "clunky" noises, = which i'm pretty sure aren't xruns. I have tested it using fluidsynth = and very large buffer sizes, to eliminate the possibility of xruns. I = have ensured everything in the alsamixer is turned down. Particularly, when a note is turned off in fluidsynth, shortly after you = get a pop.=20 I have tried using all of the via82xx driver's options, ie. = dxs_support=3D0,1,2,3, ac_97_quirk=3D0,1,2,3,4 to no avail. I have also = tried passing no-hlt to the kernel, which helps just a little. Interestingly the 2.4 kernel OSS drivers do the same. VIAs own OSS = drivers do not, and are very quiet, but their latency is quite high. = The source is available to all of these drivers. The windows drivers are = fairly quiet as well. I am pretty sure this is a problem with the alsa drivers using this = particular chip, as I have a few friends who are experienced with alsa = attempting to use the same board with similar problems. Also, I have = used the same setup (fluidsynth / alsa) on a via 8233a based board and = it worked fine. It could be as simple as an unnaccesible mixer channel being left = unmuted. Has anyone else experienced this problem? Does anyone have any tips or = advice? I would really like to fix this, as I am a professional programmer, = though I have no experience of linux device drivers, and only a little = experience in linux generally. Is there a guide to how alsa drivers = work anywhere? Any information which would help me sort this would be = gratefully recieved, Thanks, John Matthews. ------=_NextPart_000_0032_01C49666.29D4D0A0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

Hi,

I'm trying to develop a complete system = /=20 distribution using the via "mini-itx" platform. The idea is that = we take=20 in sensor positions from analog sensors and output sounds based on the = position=20 of these sensors. This setup is used for music therapy, with = disabled=20 children producing music using, for example, ultrasonic position = sensors=20 (amongst other types of sensor). I've=20 written some code to accept input from the alsa sequencer and act as a = midi=20 router, and I'm using fluidsynth as an output synthesiser.

The mini-itx board is a very small form = factor=20 fully integrated pc motherboard with a via c3 processor. The = sound=20 controller on this board is part of a via 8235 = southbridge.

The snd-via82xx alsa module works fine = on this=20 board, apart from the fact that it is very, very noisy - unusably = so. =20 There is a background drone and whenever the processor does something = you get=20 "clunky" noises, which i'm pretty sure aren't xruns. I have tested = it=20 using fluidsynth and very large buffer sizes, to eliminate the = possibility=20 of xruns. I have ensured everything in the alsamixer is turned=20 down.

Particularly, when a note is turned off = in=20 fluidsynth, shortly after you get a pop.

I have tried using all of the via82xx = driver's=20 options, ie. dxs_support=3D0,1,2,3, ac_97_quirk=3D0,1,2,3,4 to no = avail. I=20 have also tried passing no-hlt to the kernel, which helps just a=20 little.

Interestingly the 2.4 kernel OSS = drivers do the=20 same. VIAs own OSS drivers do not, and are very quiet, but = their=20 latency is quite high. The source is available to all of = these=20 drivers. The windows drivers are fairly quiet as well.

I am pretty sure this is a problem with = the alsa=20 drivers using this particular chip, as I have a few friends who are = experienced with alsa attempting to use the same board with similar=20 problems. Also, I have used the same setup (fluidsynth / alsa) on = a via=20 8233a based board and it worked fine.

It could be as simple as an = unnaccesible mixer=20 channel being left unmuted.

Has anyone else experienced this = problem? =20 Does anyone have any tips or advice?

I would really like to fix this, as I = am a=20 professional programmer, though I have no experience of linux device = drivers,=20 and only a little experience in linux generally. Is there a guide = to how=20 alsa drivers work anywhere? Any information which would help me = sort this=20 would be gratefully recieved,

Thanks,

John = Matthews.

------=_NextPart_000_0032_01C49666.29D4D0A0-- ------------------------------------------------------- This SF.Net email is sponsored by BEA Weblogic Workshop FREE Java Enterprise J2EE developer tools! Get your free copy of BEA WebLogic Workshop 8.1 today. http://ads.osdn.com/?ad_id=5047&alloc_id=10808&op=click