1. This forum section is a read-only archive which contains old newsgroup posts. If you wish to post a query, please do so in one of our main forum sections (here). This way you will get a faster, better response from the members on Motherboard Point.

Using opencores I2S as master

Discussion in 'Embedded' started by cbr, Oct 19, 2006.

  1. cbr

    cbr Guest

    Sorry for the cross postings but I really need help.

    I'm trying to use the Opencores I2S master logic as the driver for my
    test platform to generate test audio signals.

    The core came configured with SCK = 2.77 MHz and WS(left/right clock)=
    69.44 KHz.

    I would like to be able to reconfigure the core to generate SCK=3.07MHz

    and WS=48 KHz.

    I played around with the conf variable but could not get the ratio I'm
    looking for.

    I read the documentation but I still cannot understand. An explanation
    would certainly help.

    According to the manual,
    The sample rate is given by bit_rate/(RES * 2)

    If I choose the sample rate to be 48 KHz, and the resolution is
    20-bits,
    the bit rate would be 1.92 Mbps.

    However, the RATIO would then be calculated as follows.

    RATIO= (wishbone_bus_clock - (sample_rate * RES * 8)) /
    (sample_rate * RES * 4)

    wishbone_bus_clock= 50 MHz
    sample rate = 48 KHz
    RES=20 bits

    which would then be equal to ~22 (10110)
    This is not giving me the values of 48KHz for WS and 3.072 MHz for
    i2s_sck.

    Could you please help?

    Thanks,
    cbr
     
    cbr, Oct 19, 2006
    #1
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.