xmos soundcard ，change synchronous to asynchronous？ Topic is solved

[superganbu]

Dear，
We have the xCORE-200-Multichannel-Audio-Platform-2V0 and we design our soundcard base on XMos， they both have the problem。
We use the bord to play the Sine sweep signal，and record ，then cmpute the FR（frequency response），we found that sometimes the FR is droped on some frequency point and get well at once，several times one day。
How to deal with the problem,any advise?

Is it because of the USB synchronous transmission？
Can we change the transmission to asynchronous？Is there the example software that provide？

Thank you very much，Looking forward to your reply.

[AlexAdvice]

XMOS USB is always async.

[akp]

Yup. Probably your test setup or you built the program wrong. Advise you to output sine to an audio analyzer, oscilloscope with FFT, etc for the DAC testing. For the ADC testing using a sig gen. So you know your instruments are good.

If you are 100% sure you're using the factory source for the MC Audio board and you don't have any weirdness going on (like JTAG debug output selected instead of xscope) then it's likely your PC.

[superganbu]

Hi akp
We download the soft (sw_usb_audio-[sw]_6.15.2rc1.zip) from XMos website  and select ( app_usb_aud_xk_216_mc) (2i8o8xxxxx_tdm8) ;
We use xTIMEcomposer Version Community_14.3.2;

Is it right?

Thank you.

[akp]

Yes that's correct. However, you need to ensure that if you are running under xtag that you ensure the debug output is selected as xscope and not jtag. Jtag debug output is slow and will prevent real time operation.

But it seems to me the other issue is the instruments you are using for testing, you didn't specify that.

[superganbu]

Hi akp
The debug select is no problem.
We use the soundcheck.
We found that the drop times is less when we use a better PC.
What is the lowest demand for the PC, or how to setup the PC, and any advise?

Thank you very much，Looking forward to your reply.