Re: [9fans] sb16(?) problem: audio timeout / mpg123: problem: division-by-zero

Re: [9fans] sb16(?) problem: audio timeout / mpg123: problem: division-by-zero

[Russ Cox]

Look in your BIOS to see if there is an option
about whether to configure PNP devices.  Try
toggling it.  (I don't remember what the right
setting is.)

I think that the option should be on, because for PNP
SB cards we try to use whatever interrupt the
card has already decided upon.

Russ

Re: [9fans] sb16(?) problem: audio timeout / mpg123: problem: division-by-zero

[Axel Belinfante]

Thanks to those who reacted; I solved the problems.

I got the sb working by simply trying more irq/dma
configurations in plan9.ini (in my case: irq=5 dma=1 works).

W.r.t. mpg123 it looks like my hack-around works.
For the archives:
version: mpg123-0.59r
problem: division-by-zero
hack-around:

--- layer3.c	Wed Apr 21 17:25:18 1999
+++ /tmp/layer3.c	Fri Apr  5 16:23:52 2002
@@ -169,10 +169,14 @@

   for(i=0;i<16;i++) {
     double t = tan( (double) i * M_PI / 12.0 );
-    tan1_1[i] = t / (1.0+t);
-    tan2_1[i] = 1.0 / (1.0 + t);
-    tan1_2[i] = M_SQRT2 * t / (1.0+t);
-    tan2_2[i] = M_SQRT2 / (1.0 + t);
+    double tt = (1.0+t);
+    if (tt == 0.0)
+	tt = 0.00001;
+    /* fprintf(stderr, "tt=%f\n", tt); */
+    tan1_1[i] = t / tt;
+    tan2_1[i] = 1.0 / tt;
+    tan1_2[i] = M_SQRT2 * t / tt;
+    tan2_2[i] = M_SQRT2 / tt;

     for(j=0;j<2;j++) {
       double base = pow(2.0,-0.25*(j+1.0));

Regards,
Axel.

[9fans] sb16(?) problem: audio timeout / mpg123: problem: division-by-zero

[Axel Belinfante]

I'm playing with a soundblaster card.
With /dev/volume I can control the cd volume.
(Russ: I like your mixer program! Thanks!
 Note: on my system it needed minor changes to compile)
But, when I redirect sound bytes to /dev/audio nothing seems
to happen; after uncommenting the commented-out print statements
in /sys/src/9/port/devaudio.c  I get '#A: audio timeout' messages.

The system is a 150 Mhz pentium-s (according to boot msgs).
The sound blaster card (ISA) says while booting something like:
   creative VibraX16 PNP
It has a note (c) 1997 on the card.
(is this enough to identify it?)
Is this one simply not compatible enough? Or??

On a related note:
I installed mpg123 (using Tad Hunt's patch). When I run it,
I get a 'division by zero' error in layer3.c:172
When it breaks, i==9.
Any ideas?
(I hacked around this by inserting an explicit test; since I don't
hear the audio anyway I cannot say how that influences sound quality)

(I also installed mpeg3play, which does seem to work,
as far as I can judge without being able to hear the audio)

Thanks, as always,
Axel.