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#4762 - 12/02/2000 17:57 no audio outside player?
Verement
journeyman

Registered: 02/09/1999
Posts: 97
Loc: Boston, MA, US
After upgrading to the beta9c developer image, I find I can no longer get any audio output from my own programs. (The player runs fine, but when I exit and run something else, there is no sound.)

I've verified the mute status with this program, and I have also played around with making sure /dev/mixer's main volume channel is set to a reasonable level, but still I cannot get any sound from programs that used to work.

Any ideas?
-v



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#4763 - 13/02/2000 03:30 Re: no audio outside player? [Re: Verement]
Jazzwire
addict

Registered: 09/06/1999
Posts: 483
Loc: Guernsey
This is from memory, so could be wrong...
When I built a kernel (so I could get a custom logo) I noticed a few config options.
I think they were empeg audio and empeg display (both were set off in the default script)
Maybe they aren't enabled on the developer release?
If I'm talking rubbish, feel free to correct me... =)

Jazz
(List 112, S/N 00030, 4 gig blue)
_________________________
Jazz (List 112, Mk2 42 gig #40. Mk1 4 gig #30. Mk3 1.6 16v)

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#4764 - 16/02/2000 18:27 Re: no audio outside player? [Re: Jazzwire]
Verement
journeyman

Registered: 02/09/1999
Posts: 97
Loc: Boston, MA, US
Well they surely must be enabled, or how would the player software even work? :-)

I've poked at this a little more, but I still can't be sure what's keeping audio from working after exiting from the player. This stuff has worked before, so it seems likely the player is leaving the audio device in a state different than it used to.

Hugo, Mike, John, anyone want to toss me a clue?

Thanks,
-v


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#4765 - 17/02/2000 07:33 Re: no audio outside player? [Re: Verement]
Jazzwire
addict

Registered: 09/06/1999
Posts: 483
Loc: Guernsey
Well, in the kernel defaults in arch/arm/def-configs/empeg the dac and screen options were turned off... =)
I assumed that the default build options would be the ones empeg use...
Oh well, was worth a try.. =)

Jazz
(List 112, S/N 00030, 4 gig blue)
_________________________
Jazz (List 112, Mk2 42 gig #40. Mk1 4 gig #30. Mk3 1.6 16v)

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#4766 - 17/02/2000 09:04 Re: no audio outside player? [Re: Jazzwire]
Verement
journeyman

Registered: 02/09/1999
Posts: 97
Loc: Boston, MA, US
There appear to be two mutually exclusive empeg audio driver options, CONFIG_EMPEG_DSP and CONFIG_EMPEG_DAC. That explains why one of them is disabled, but I'm not sure what the history or difference is.

In any case, I've had to downgrade to beta8c until I can find an answer to my problem.

-v


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#4767 - 17/02/2000 12:30 Re: no audio outside player? [Re: Verement]
altman
carpal tunnel

Registered: 19/05/1999
Posts: 3457
Loc: Palo Alto, CA
The DAC driver is for a simple I2S dac, this is used on some unannounced products and prototype boards :)

You need the DSP driver otherwise you won't get sound - the DSP needs to be initialised to make noise.

Hugo



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#4768 - 17/02/2000 12:43 Re: no audio outside player? [Re: altman]
Verement
journeyman

Registered: 02/09/1999
Posts: 97
Loc: Boston, MA, US
In reply to:

the DSP needs to be initialised to make noise.


So... how did it get uninitialised, or more to the point, how can I initialise it?

Keep in mind I'm not doing anything different between beta8c and beta9c, yet I get sound with the former and not with the latter.

-v



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#4769 - 17/02/2000 13:04 Re: no audio outside player? [Re: Verement]
Verement
journeyman

Registered: 02/09/1999
Posts: 97
Loc: Boston, MA, US
OK, I've discovered something about a soft audio mute that was added to the kernel from beta8c to beta9a. Perhaps my problem has something to do with this?

Perhaps I should be selecting the PCM input source explicitly (and thereby turning off SAM in the process) or perhaps it is enough just to call ioctl(EMPEG_MIXER_SET_SAM)?

What is SAM, anyway?

-v


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#4770 - 17/02/2000 17:38 Re: no audio outside player? [Re: Verement]
Verement
journeyman

Registered: 02/09/1999
Posts: 97
Loc: Boston, MA, US
I found a solution to my problem, and posted it here.

-v


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