changing input/output number in app_usb_aud_xk_216_mc

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PhilippeV
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changing input/output number in app_usb_aud_xk_216_mc

Post by PhilippeV »

We have purchased a XC-AUDIO-216-MC-AB evaluation board to evaluate the XMOS audio platform solution. We want to develop a 4 to 6 channels inputs and 2 channels output system for data acquisition.

1) The Windows 10 UAC2 driver functions with the version 6.12.2 of the embedded (and flashed) application but not with a compiled 6.15.2 version (from downloaded source code).
Why the version 6.15.2 of the firmware cannot be used with the Windows 10 UAC2 driver ?

2) I am trying to compile a version of the embedded application with less than 10 inputs but the capture no longer works on the PC if I change NUM_USB_CHAN_IN (I tested with 8, 6 and 4).

If I modify only I2S_CHANS_ADC, for example 4 instead of 8, I can see that the acquisition is done only on the first 4 inputs (the samples are 0 on the other 4 inputs).
I placed a break point in the decouple function (decouple.xc file, line 742, after "else if (tmp == SET_STREAM_FORMAT_IN)").
If NUM_USB_CHAN_IN = 10, I go through the break point but not with a lower even value of NUM_USB_CHAN_IN.

Is there a reason why it is not possible to decrease the number of inputs and outputs in the embedded application?

NB: I used the build configuration: 2i10o10xxxxxx
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mon2
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Joined: Thu Jun 10, 2010 11:43 am

Post by mon2 »

Hello and welcome.

Please see if this helps:

https://www.xcore.com/viewtopic.php?t=6806
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Ross
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Joined: Thu Dec 10, 2009 9:20 pm
Location: Bristol, UK

Post by Ross »

You could well be hitting issues with windows driver caching. I'd recommend using https://www.nirsoft.net/utils/usb_devices_view.html when changing device parameters such as channel counts and not changing the decide VID/PID pair

<moved thread from StartKit to Applications>
Technical Director @ XMOS. Opinions expressed are my own