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TOPIC: USBStreamer I2S signal shapes

USBStreamer I2S signal shapes 3 years 1 month ago #33254

  • zarandok
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Hi,
I have received an oscilloscope an measured the output I2S signals direct at the output pins (without USB cable connected), please see below.
The LR-CLK seems to be Ok, but the Master and Sysem clocks a little strange. Are they suitable anyway???
Thanks!





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USBStreamer I2S signal shapes 3 years 1 week ago #33674

  • erik.vanhamme
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Both the top and bottom scope traces show signs of low pass filtering, most likely done to reduce EMC emissions. Perfectly fine.

The master clock is clearly driven by a crystal oscillator:
en.wikipedia.org/wiki/Crystal_oscillator

25MHz is a common value for oscillator crystals.

I see no obvious problems with this (I am electronics and embedded software engineer)
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USBStreamer I2S signal shapes 3 years 2 days ago #33755

  • zarandok
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Thanks!
If you say these are ok, than all right... I thought that master and system clocks should be square waves too...
Last Edit: 3 years 2 days ago by zarandok.
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