Homebrew CMI 8738 drivers Options

[d0gbert]

Hi everyone!

I'm currently working on WDM drivers for soundcards based on the C-Media 8738/8768 chip. I plan to release the entire source code under a BSD-like license sometime in the future. I'm mainly interested in the S/PDIF connectivity because the DAC of the card sucks.

For testing, you need:
- a CMI 8738-MX/8768 based soundcard with S/PDIF (which are available for around 10-15 USD)
- Windows 2000/XP

Some of the features are:
- bitperfect S/PDIF output for 16bit 44.1/48/88.2/96kHz stereo signals through kernel streaming / dsound / waveout
- bitperfect AC3/DTS passthrough
- multi-channel output (that disables the S/PDIF output port unfortunately)
- recording support
- basic mixer support
- UART support (but disabled for now)

Apparently, the C-Media chip supports only 16 bit contrary to the claims in their specs. I haven't been able to get 24bit output even with the official drivers. But 96kHz output seems to work fine on the newer 8738 chips.

You can help me by posting your chip version and configuration, and testing whether 16bit/96kHz and 24bit/48kHz output through kernel streaming works (foobar2000, winamp have the necessary plugins). I'm specifically looking for people who have means to tell a 16bit S/PDIF stream from a 24bit stream.
When the driver loads, it prints the version of your chip to the kernel debugger. You need a running instance of DebugView (http://www.sysinternals.com/Utilities/DebugView.html) to catch the strings. In other words: open DebugView before updating the drivers.

Note that the drivers aren't signed, so you have to install them manually (Update Driver => Install from a list or specific location => Don't search. I will choose the driver to install => Continue anyway).
A 64-bit build has been successfully tested, and I'll probably release a build sometime soon.

Here are the download links for the latest version:

http://code.google.com/p/cmediadrivers

So long,

dogbert

This post has been edited by d0gbert: Mar 14 2008, 20:30

[Any2]

Hello

every time I have been installing CMI8738 64-bit driver (recently it was 1.01, 1.02 and 1.03 version) I've got following error (copy->paste from SystemEventLog):

Error code 000000000000000a, parameter1 fffff6fb7ea04008, parameter2 0000000000000002, parameter3 0000000000000000, parameter4 fffff8000101f605.
For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

Could you take this event into consideration when you will be developying this very interesting driver.
BTW it happens each time the computer is booted-up and shutted-down but not always it restarts (sometimes only above event is logged in).

Best regards
Any

[Dogbert]

every time I have been installing CMI8738 64-bit driver (recently it was 1.01, 1.02 and 1.03 version) I've got following error (copy->paste from SystemEventLog):

Error code 000000000000000a, parameter1 fffff6fb7ea04008, parameter2 0000000000000002, parameter3 0000000000000000, parameter4 fffff8000101f605.
For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

Thanks for the bug report. Can you provide me with a minidump of the crashes for further analysis?

[Any2]

Thanks for the bug report. Can you provide me with a minidump of the crashes for further analysis?

Yes,
how I can provide you with minidumps? Send via email or is it possible to add into the forum post?
Please answer and I will deliver minidumps.

[Dogbert]

Yes,
how I can provide you with minidumps? Send via email or is it possible to add into the forum post?
Please answer and I will deliver minidumps.

Windows puts them into the folder "C:\Windows\Minidump" everytime the system crashes. They are roughly ~100kB in size. Please forward the dump(s) to my mail address which you find on my homepage.

This post has been edited by Dogbert: Feb 3 2007, 21:55

[Any2]

Windows puts them into the folder "C:\Windows\Minidump" everytime the system crashes. They are roughly ~100kB in size. Please forward the dump(s) to my mail address which you find on my homepage.

already sent.
Hear from you tomorrow (my time zone is GMT+1 so we have night now)