Any CMedia CMI8788 "Oxygen" and ASUS Xonar D1 "virtuoso" documentation available?

Any CMedia CMI8788 "Oxygen" and ASUS Xonar D1 "virtuoso" documentation available?

[John L. Utz III]

Hi;

I just tried to find the docs for the CMI8788 on www.cmedia.com.tw and i 
was not successful.

Nor have i been able to find any virtuoso docs at www.asus.com.

I know that Clemens wrote the driver, but I dont know if it was written 
from scratch with docs or ported from a 4front driver.

currently, there are some bugs with channel mapping on the rear channel 
in Surround40 mode that i would like to fix

tnx for any info you folks can provide

johnu

Re: Any CMedia CMI8788 "Oxygen" and ASUS Xonar D1 "virtuoso" documentation available?

[Clemens Ladisch]

John L. Utz III wrote:
> I just tried to find the docs for the CMI8788 on www.cmedia.com.tw and i
> was not successful.

That website has a datasheet which doesn't contain much of interest.

There is a datasheet with register specifications, but it is only
available under NDA.

> Nor have i been able to find any virtuoso docs at www.asus.com.

The only difference between the CMI8787/CMI8788/AV100/AV200 chips is the
label on top of the chip.

> I know that Clemens wrote the driver, but I dont know if it was written
> from scratch with docs or ported from a 4front driver.

I started with an ALSA driver that was written by someone at C-Media,
but it was so incomplete and buggy that I started over from scratch.
I never signed an NDA.

> currently, there are some bugs with channel mapping on the rear channel
> in Surround40 mode that i would like to fix

In 4.0 mode, the "rear" channels go to the "surround" jack.  The
"surround" and "back" jacks behave like described in the manual.

The PCM data from the computer is organized as (up to) four two-channel
pairs.  There are four DACs that each play a two-channel pair of PCM
data.  The "play routing" register contains four two-bit fields that
specify, for each DAC, the number of the channel pair that is to be
played on this DAC.  This allows rerouting (by exchanging some fields)
or duplicating of channels pairs (by having the same source for multiple
DACs).  All this is handled in the oxygen_update_dac_routing() function.


HTH
Clemens

Re: Any CMedia CMI8788 "Oxygen" and ASUS Xonar D1 "virtuoso" documentation available?

[John L. Utz III]

Hi Clemens;

thankyou for the response.

Clemens Ladisch wrote:
> John L. Utz III wrote:
>> I just tried to find the docs for the CMI8788 on www.cmedia.com.tw and i
>> was not successful.
> 
> That website has a datasheet which doesn't contain much of interest.

yah, i read that. :-(

> There is a datasheet with register specifications, but it is only
> available under NDA.
> 
>> Nor have i been able to find any virtuoso docs at www.asus.com.
> 
> The only difference between the CMI8787/CMI8788/AV100/AV200 chips is the
> label on top of the chip.

Oh, thankyou!

>> I know that Clemens wrote the driver, but I dont know if it was written
>> from scratch with docs or ported from a 4front driver.
> 
> I started with an ALSA driver that was written by someone at C-Media,
> but it was so incomplete and buggy that I started over from scratch.
> I never signed an NDA.

ok, understood.

>> currently, there are some bugs with channel mapping on the rear channel
>> in Surround40 mode that i would like to fix
> 
> In 4.0 mode, the "rear" channels go to the "surround" jack.  The
> "surround" and "back" jacks behave like described in the manual.

yup, that works.

> The PCM data from the computer is organized as (up to) four two-channel
> pairs.  There are four DACs that each play a two-channel pair of PCM
> data.  The "play routing" register contains four two-bit fields that
> specify, for each DAC, the number of the channel pair that is to be
> played on this DAC.  This allows rerouting (by exchanging some fields)
> or duplicating of channels pairs (by having the same source for multiple
> DACs).  All this is handled in the oxygen_update_dac_routing() function.

thankyou for the huge fat hint. :-)

we have some transposed channels when we run our app, i can probably fix 
this.....

> HTH
> Clemens
>