Hi !

Yes, you are right, full duplex doesnŽt work correctly. I just never had a card, which is full duplex until now (bought a PCI128 too).

I realized the same problems as you did:

1. with OSS/Free, the card only works in full duplex with BIG audiobuffer sizes.(kernel 2.1.131)
2. DidnŽt try OSS/Linux, because it crashed my computer (alpha) the last time I installed it. You could try setting the audiobuffer size and look if it works ..
3. After trying ALSA I realized, that the ALSA code in pd is only full duplex with two soundcards. Then, IŽm having problems with ALSA under Alpha anyway, which I have to investigate further.

In my opinion the OSS driver just donŽt work as documented, or rather, the documentation lacks a specification of minimum audiobuffer sizes.

What I will do against it:

• Look if I can tweak the code, so that it will work under OSS/Free.
• Try to make the ALSA support clean.
• Investigate the possibility of 4 channel output :)

until then (early Jan), you could only look into s_linux.c and try to fix OSS code yourself..

Merry Christmas

Guenter

-----Original Message----- From: Michael Lechasseur [mailto:mlecha@music.mcgill.ca] Sent: Saturday, December 19, 1998 10:07 AM To: PD List Subject: Full-duplex questions

I'm having problems with full-duplex mode in Linux.

I'm using a Sound Blaster PCI128 with OSS/Linux and alternately with ALSA drivers.

The ALSA drivers seem very nice BTW, a bit of pain to setup, but they sound great.

With OSS/Linux I get this message when starting pd: pd: dacs died.. switching to alternate time source

the same error occours with the -adc switch, -dac works fine.

Using the ALSA drivers, which are full duplex, pd starts in -dac mode even if it the switch is not specified. ie: I get the "write only" message from pd.

Using the ALSA compatible mixer "xamixer" I can mix multiple inputs with no problems while listening to the output.

I don't know if this is the best way to test full-duplex capabilities in Linux? Any ideas?

Does pd support 16-bit full-duplex audio? It seems to work ok in win95.

Thanks.