How to modify can be achieved by USB to 8 and 9 microphones collected PCM data(Reference xCORE ARRAY MICROPHONE)? Topic is solved

[shanghaiwangyong]

Hello,

We designed 9 digital microphone array boards, the reference development board is xCORE ARRAY MICROPHONE (7 microphones), the reference project is app_usb_aud_mic_array,

1, how to modify can be achieved by USB to 8 microphones collected PCM data(for example, using ALSA's arecord in Linux PC)?

2, how to modify can be achieved by USB to 9 microphones collected PCM data?

Attachment is design change.

Best Regards,

Shanghaiwangyong

[andrewxcav]

That reference design should support up to 16 Mics (I think there is a #define in mic_array_config.h).

Going up to 9 shouldn't be a problem, just be aware that anything exceeding 8 mics at 44.1 kHz. will require that you use the UAC2.0 build config as the lower speed interface won't handle that. Using the faster interface is almost always the correct choice, however it will require Windows users to install a driver.

If you ask ALSA for N mics it will probably give you as many mics as you have up to N. If N is greater than the number of mics you have it will start duplicating. Also be aware of software sample rate modifications that can happen without your knowledge.

[shanghaiwangyong]

Thank you for your reply. This problem has been solved.