This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

PCM3168A

Other Parts Discussed in Thread: PCM3168, PCM3168A, PLL1707

Hello

I am implementing an PCM3168A Audio Codec into the BeagleBoard by using the ALSA framework. And so far i got my first audio signals out of the PCM3168 :-)

Till now i use the hardware control pins to setup the codec but i want to change that by using I2C for that purpose. For the clk signal generation an PLL1707 is used.

What i do not understand properly is whether the PCM3168 uses the SCKI system clock just as an reference when using the codec in master mode (internal PLL ?) and MSDA[2:0] DAC Master/slave mode select registers (and MSAD[2:0]) do configure the correct LRCKAD/DA and BCKAD/DA or whether i have to adjust also the external clock (applied to SCKI) to the appropriate mode.

And the second question i have is how i can calculate the delay which occurs between applying the digital audio sample and the converted analog audio signal (for the DAC and vice versa for the ADC). Is it just the formula from the digital filter group delay -> DAC(single, dual) 28/fs or is there an additional delay to consider.

Thanks

Wendelin 

  • Hi, Wendelin,

    Sounds like a cool project! 

    Table 8 shows the various settings and clock requirements for this device.

    The delay is dominated by the 28/fs figure.

    Let us know how this ends up working for you!

    -d2

  • I'm interested in an easy way to get pro audio in and out of the Beaglebone as well. Is it possible for you to share some more about your design? If you've developed board or cape for Beaglebone, I would be interested in purchasing that from you. Thank you for your help.

  • Hello Mike Gilman

    I started to develop an pcb for the pcm3168 (for the beagleboard!!) and also to develop an alsa linux device driver but i did change my hardware-concept slightly so i did not finish it yet. At last the pcm3168 did play 4 audio outputs per i2s-tdm (channel 1, 3, 5, 7). the rest is untested.

    i will resume the device driver development in some weeks, but if you like i can give you my unfinished files as a starting point for your own development.

    About the pcb, i don´t have one in spare but i could give you my gerber files -> the pcb still needs some external setup and level translation to work with the beagleboard (i don´t know about the differences to the beaglebone).

    So i would say its still far away from ready but i work on it ;-) 

    Kind Regards 

    Wendelin

  • Please do send me any information you can on this. Thank you for being so generous. If this becomes more than a personal project for me I'll let you know so proper credit can be given for your work. If there is anything I can do to help you, please don't hesitate to let me know. I updated my profile's public email so you can send me the info.