Re: [Alsa-user] Intel8x0 (nforce2) with spdif-out: no sound from line-in (bttv bt878 card) - help please

[Andy S. <an...@da...>]

Thanks for the info Takashi.  You say:
[quote]
The direct output from line-in to spdif isn't always supported on most
of motherboard chips.
It depends on AC97 codec chip.
[/quote]

Does anyone know how I find out if this is the case for my card? 
(NFORCE2 audio on ASUS A7N8X Deluxe)

As a n00b I'm slightly confused - in WinXP the Nvidia mixer has an 
option to 'digitise the line input' - when I do this I get sound.  This 
suggests to me that the direct output from line-in to spdif is 
supported, at least in windows.  Is this a fair assumption, and if so 
how do I achieve the desired result in Linux under ALSA?

Thanks
Andy



Takashi Iwai wrote:
> At Thu, 25 Nov 2004 11:29:13 +0000,
> Andy Stone wrote:
> 
>>Current set-up:
>>
>>Gentoo kernel 2.6.9-r4
>>Alsa 1.0.6 compiled into the kernel
>>Hauppauge tv card (BT878 based, using bttv kernel module)
>>ASUS A7n8x board with onboard NFORCE2 sound (using alsa intel8x0 driver)
>>digital speakers, connected using spdif
>>external cable conection from tv card line-out to sound card line-in
>>
>>Up untill 3 days ago there was also:
>>Audigy pci card (using alsa audigy driver), with the NFORCE2 audio 
>>disabled in BIOS
>>
>>I had to remove the audigy card (shame - it was a good card) and so I 
>>enabled the NFORCE2 sound in the bIOS and chose to use alsa drivers. 
>>With some playing around I have got most audio to work (mp3 files, cd 
>>audio, dvds etc) but cannot for the life of me work out how to get tv 
>>sound (I get pictures though).
>>
>>Opening tvtime with alsamixer already open, I see that the line channel 
>>unmutes itself and turns up to 100%. So sound input is definitely 
>>detected. I think that what might be happening (excuse me, I'm a n00b) 
>>is that the line in sound is not being digitized before being sent out 
>>via the spdif connection. Certainly when I dual-boot into WinXP where I 
>>use official Nvidia drivers, I have to turn on the option in the Nvidia 
>>mixer to digitize the line input if I want to hear any telly.
> 
> 
> The direct output from line-in to spdif isn't always supported on most
> of motherboard chips.
> It depends on AC97 codec chip.
> 
> 
> Takashi
>