Talk:Btaudio (bt878)

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ALSO initialization problem.

I have also the same initialization issuse as Petr Vandrovec. However, the difference is that I can make bt878 run after it is initialized by another windows driver, btwdmdrv.

I am very sure this description is valid, because I have product 10 pcs of the same bt878 card. Some of these are ok to initailize directly by Btaudio, but other cards are failed. These failed cards can be initialized after btwdmdrv.

Comment (Dave Liontooth): This is very interesting -- and since the driver is open source, it may be possible to figure out what the problem is with those bttv cards that don't support getting the sound from the PCI bus. Did you tell Petr about this?

Reply (YT): No, I have no discussion with Petr. However, I will settup a windows debug environment to get what difference, maybe in 2 weeks.

Report (YT): Sorry, I was busy and forgot my account. Right now I have a good result about this initialization issue. The difference between windows driver and ALSA-Btaudio is not helpful for this issue. However, I have made all cards success to capture analog audio only by toggling ARESET of Bt878. Within Bt878's datasheet, the posistion of ARESET register is at 0x5B of function 0, BUT this is an erratum. According to Conaxien's errata document, it should be at 0x058. I have tried it, and been successful for all of my 2 cards with 8 bt878 chips. Maybe you can insert {btwrite(0x080, 0x058); btwrite(0x0, 0x058); } into your V4L driver, then and see what results in.