XS1 audio - clocks generation problem

genap · Post by **genap** » Mon Dec 20, 2021 4:35 am

I have XS1-U8A usb audio (TDM8, inputs only, 48kHz) project with the XMOS as a master.
Most of the time LR and BCLK are generated properly on power-up (pic 1).

1-48kHz_frame.jpg: (161.99 KiB) Not downloaded yet

1-48kHz_frame.jpg: (161.99 KiB) Not downloaded yet

But sometimes on power-up the LR frequency is about 45.2kHz instead of 48, with some jitter.
I've noticed that in this case the first bit in each 32-bit channel is longer (high level is 5 times longer than normal, occasionally jumping to 4 times, therefore is jitter).
It makes LR pulse longer and LR frequency lower. See pics 2 and 3.

2-45.2kHz_frame.jpg: (157.25 KiB) Not downloaded yet

2-45.2kHz_frame.jpg: (157.25 KiB) Not downloaded yet

3-45.2kHz_LR_BCLK.jpg: (120.74 KiB) Not downloaded yet

3-45.2kHz_LR_BCLK.jpg: (120.74 KiB) Not downloaded yet

I had quite a few XS1 audio projects, but never saw anything like this.
Is there any explanation to this situation?

Post by **Ross** » Wed Apr 05, 2023 9:28 pm

Did you resolve this?

XS1 audio - clocks generation problem

XS1 audio - clocks generation problem

Re: XS1 audio - clocks generation problem