Simple questions about MIC ARRAY BRD XK-USB-MIC-UF216

[bryant]

Hi all,

Does the xCORE MICROPHONE ARRAY BOARD (XK-USB-MIC-UF216) act as a 7 channel USB microphone such that it can used with application like Audacity?

Does the 3.5 mm audio jack output two channel audio at line levels? Can I select which mic signals are sent to the 3.5 mm jack? Can the board be configured to mix all the mic signals sent to the audio jack?

Is the Ethernet connecter used for command, status, and configuration of the board using TCP/IP? Can audio be captured over the Ethernet connection?

Are there standard preset configurations such as multi-channel mic output over USB, single channel analog output, and multi-channel analog output? Does the board require low level programming before it can be used?

Thank you for your help.

Bryant

[Ross]

Hi, not sure how familiar you our with XMOS usb audio devices, but basically it is provided as framework with provided applications customising this frame work (e.g. setting channel counts etc) and extending it (i.e. adding support for a certain DAC) for the various XMOS boards.

Normally I would expect someone to start with an example application (probably the closest you your product) and use this as a base for your customisation.

Each application has various build configurations to show off the features of the board/framework etc. For the mic board the is currently a build config that simply transports the 7 mics to USB (and gets stereo output front the host just like a normal USB sound card). So yes to audacity..

There is also a simple summing example which simply sums up all mics and outputs the sum over USB (this is programmed to be enabled/disabled on a button), it also applies a simple gain to all channels - again based on the buttons.

You can program channels to go wherever you like, hard-coded, based on some I/O, use the mixer controlled via the host. Everything is in software and written in a high-level language so its highly flexible.

The two-channel DAC actually has a built in headphone amp.

The ethernet jack is mainly there for the possibly for an AVB mic, though this isn't a priority for XMOS right at the moment - you can of course program the board to run all the usual ethernet demos etc on it or even port the AVB stack should you wish..

The board doesn't require programming before it can be used, but keep in mind its not a product, it is a platform for customers to evaluate the design before committing to make their own product (of course all the code etc is production quality)

[bryant]

Ross,

Thank you for your detailed reply.

The XMOS USB devices are new to me but the features and physical description given on the Web site look like a good fit for the beam forming and noise cancellation research that I am doing. Having a 7 channel USB microphone arranged in a hexagon is an ideal starting place. It sounds like the example code will get me started with what I need. Hopefully it won't be too difficult to port our algorithms to the device if we move to production with this SOC. The summing example might be a good place to start with that effort.

Thanks again.

Bryant

[henk]

Hi Bryant,

It could be programmed to do all of the above; but I doubt that anybody has made a packaged piece of software that does all of the above.

Likely somebody has ported the USB-Audio software, which would implement a 7-channel microphone to USB.

For the bespoke requirements, such as controlling the board over Ethernet, you will likely have to write the software for the board to do that.

Maybe somebody else can comment on whether the USB Audio design runs on that board, and whether that has a mixer built-in or not.

Cheers,
Henk

[bryant]

Henk,

Thank you for the help.

Fortunately I don't need Ethernet access to the board but it might have been convenient. The other features look perfect for my research project. Thanks again for taking the time to reply.

Bryant

[Ross]

Sorry, we have some issues on the site which has caused posts in the thread to become out of order..

[bryant]

Ross and Henk,

Any ideas how to actually buy two of the array microphone kits and have them shipped to the States? I reached out to XMOS sales several days ago through the Web site and again in a support ticket but still no response.

Bryant

[bryant]

All,

I received the UF216 mic array development board a few weeks ago. It took awhile to arrive which meant that our first round of testing was done with a hand built mic array. I finally have time to try this board out.

I found the USB audio example project and was able to build it and load it on the board. It worked perfectly as a 7 channel USB mic! Exactly what I needed! The example was easy to modify. I changed the example code so that I could adjust the gain in dB and use the LEDs on the board to show the current gain. This makes it easier to use in our lab. So far, this is the only thing that I have tried to do with the board but I have to admit that I'm loving this platform so far! Thanks for pointing me in the right direction.

Regards,
Bryant

[Ross]

Thanks for letting us know how you are getting on and the great feedback. Good luck with the project(s)!