Open-source USB interface: Audio Widget

[nikkov]

Hello all!

I work with another avr32-based device for usb-audio (and in future as standalone player). My firmware code is based on asf 2.0 with USB Audio code from sdr-widget project.
I tested my device on Windows with Thesycon USB Class 2 driver from Wavelength USB Dac (i found only one UAC 2.0 driver for Windows for tests). With some modifications from sdr-widget code my device is working successfully on Windows.
I will glad to help writing open-firmware device and Windows driver.

schematic my device

Nikolay

P.S. UAC 1.0 also is working on Windows with my device (44100 and 48000 Hz)

[alexlee188]

Hi Nikolay,

Excellent !!!

The audio-widget firmware source is hosted at github. Let us know if u are interested in joining the development work and help us test against the Thesycon driver :-)

It will be really nice to have an open source win uac2 driver. U might like to start a repo at github as well and we in the sdr-widget/audio-widget will be glad to help out.

Your project looks very interesting and it is our hope that many uac2 devices will be developed in part encouraged by our open source firmware :-)

Alex

[nikkov]

Hi Alex!

I am ready to help the owner SDR-Widget with debugging on Windows. Unfortunately my device is somewhat different from the SDR-Widget, therefore, requires code changes are not related to USB Audio.

I have no experience in driver development, so I can't take the development itself, but I can help in testing and debugging.

Nikolay

[blushift]

An open source Windows driver will always be difficult because of the relatively-new Windows x64 driver signing requirement. Basically, all kernel modules loaded on Windows x64 must be signed by a trusted authority, and the only authorities that are still around charge a fair bit (~$1k) for a private key to sign with. It can be avoided for development by setting "test signing" mode, but setting that would never be suitable for distribution.

I've been spending some time poking at a driver; however, I think I'm going to give up because of the above. I didn't know about it when I started, and didn't notice it because I was playing in a 32-bit virtual machine until I tried it on a 64-bit VM. The Thesycon and C-Media drivers have commercial backing, so they can afford to sign their drivers.

[tdtsai]

Hi
If you want to start a open source WDM audio driver maybe you can start here. cmediadrivers - Open Source WDM Drivers for C-Media 8738/8768 based soundcards - Google Project Hosting . This is a opensource WDM Audio driver. And this is the only one that I can find open source audio driver.
Its seem MS don't want to provide UAC 2.0 driver in Windows even Mac OSX had support it. Basically C-Media's driver only support their UAC 2.0 device. If you want to use Thesycon's driver on your device you need extra fee for it.
Does any know how many device Thesycon's driver had supported?

Originally Posted by blushift

An open source Windows driver will always be difficult because of the relatively-new Windows x64 driver signing requirement. Basically, all kernel modules loaded on Windows x64 must be signed by a trusted authority, and the only authorities that are still around charge a fair bit (~$1k) for a private key to sign with. It can be avoided for development by setting "test signing" mode, but setting that would never be suitable for distribution.

I've been spending some time poking at a driver; however, I think I'm going to give up because of the above. I didn't know about it when I started, and didn't notice it because I was playing in a 32-bit virtual machine until I tried it on a 64-bit VM. The Thesycon and C-Media drivers have commercial backing, so they can afford to sign their drivers.

[nikkov]

Originally Posted by tdtsai

Does any know how many device Thesycon's driver had supported?

I just added my custom VID/PID to thesycon .inf files and installer successfully found my device.

Original inf file contains only XMOS devices

;************************************************* *****************************
; Models sections
;------------------------------------------------------------------------------
[_Models]
"XMOS XS1-L1"=_Install, USB\VID_20B1&PID_0001
"XMOS XS1-L1"=_Install, USB\VID_20B1&PID_0002
"XMOS XS1-G4 XDK"=_Install, USB\VID_20B1&PID_AD10
"XMOS XS1-L2"=_Install, USB\VID_20B1&PID_0004

[nikkov]

Exist another open source USB driver for EMU CA0188- and CA0189-Based external audio devices, but I haven't tested it

[tdtsai]

Hi nikkov:
I had check the URL you provided. This source code should workable. But its seems only support Creative EMU UAC 1.0 device.

Originally Posted by nikkov

Exist another open source USB driver for EMU CA0188- and CA0189-Based external audio devices, but I haven't tested it

[zelter]

Hi Børge,

I'm interrested to buy a kit / board (AB-1 combo). Are any available?

Cheers,

Zelter

[borges]

Hi Zelter,

not right now, but I have started sourcing components for a new batch! I'll cross-post updates here and on the Audio-Widget list.

The 22.5792MHz oscillator isn't really that mainstream, so delivery time of that one is the largest stumbling block right now.

Børge