From alsa-user-owner@alsa.jcu.cz  Tue Oct  6 19:37:48 1998
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Date: Mon, 5 Oct 1998 19:08:02 +0200
From: Rutger Nijlunsing <rutger@wingding.demon.nl>
To: alsa-user@alsa.jcu.cz
Subject: [perex@jcu.cz: Re: Buffer size]
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> > I'm trying to create a driver for MikMod for native ALSA support, for
> > which I've got a working version now, but I can't use the full 128Kb
> > buffer on my SB16 in native mode:

> Can you send me 'cat /proc/asound/0/sb16', too??

[root@wingding internet]# cat /proc/asound/0/sb16 
SB16 DMA usage

Playback DMA  : auto (16-bit)
Record DMA    : auto (inactive)

[root@wingding internet]# cat /proc/dma 
 1: Sound Blaster 16
 4: cascade
 5: Sound Blaster 16

[root@wingding internet]# cat /proc/asound/version 
Advanced Linux Sound Architecture Driver Version 0.2.0-pre7.
Compiled in Sep 19 1998 for kernel 2.1.122.


Code which sets the fragments:

	playback_params.fragment_size = fragsize;
	playback_params.fragments_max = numfrags;
	playback_params.fragments_room = 1;
	err = snd_pcm_playback_params(pcm_handle, &playback_params);

...with fragsize=4096 and numfrags=255 gives:

[root@wingding internet]# cat /proc/asound/0/pcm0
DSP v4.5

Playback
  Mode           : native
  Format         : Signed 16-bit Little Endian
  Rate           : 44100Hz [requested 44100Hz]
  Channels       : 2
  Buffer size    : 131072
  Buffer used    : 65536
  Fragments      : 16
  Fragment size  : 4096
  Fragments room : 1
  Fragments max  : 15
  Underruns      : 0
  Total underruns: 2
Record isn't active.


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