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TAS6424EQ1EVM: No output when playing USB audio

Part Number: TAS6424EQ1EVM
Other Parts Discussed in Thread: TAS6424


I am trying to use the ALSA library to play audio on the TAS6424 EVM. I am unable to play sound unless I enable the channels manually on the I2C line. Then I can stream audio via USB. Is there anyway to use the ALSA library to configure this module via USB (clear the warning, configure the channels to play mode, etc). I know this can be done using the TI software, but I need to do it headless over USB.

Thank you,


  • Tara,

    The TAS6424Q1EVM is a basic Evaluation Module to be used with our PPC3 GUI and an digital audio source.  The ALSA library is not supported by our team.  If the library does not support I2C commands then it cannot turn our amplifier on.  You will need to use the GUI or another means to generate the I2C commands.

    Gregg Scott

  • Hi Gregg,

    From the datasheet it looks like the I2C commands can be sent over USB (the USB input will convert to I2S and I2C inputs). I believe that is how the PPC3 software is communicating the controls to the device (over USB). Is that part of the USB Audio standard, or is that using a different TI specific protocol? The main thing I am trying to do is programmatically configure and play audio on the device all over USB without using the PPC3 GUI. 

    Thank you,


  • We wrote our own driver for the I2C controller that is on the pcb.  You will need to write your own code to communicate via I2C and then connect directly to the I2C traces on the pcb.