• State
  • Locked Locked
  • Replies 3 replies
  • Subscribers 98 subscribers
  • Views 356 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

fft

seeni vasan
Intellectual 580 points

hai mark

i was using the c5505ezdsp and i using the chip support library and i configure all the peripherals and it works fine and i want to know how to enable and use the fft coprocessor library inside the csl to seperate the 1khz and 5khz sinewave and out it through audio codec . i configure the audiocodec using i2c and out the data through 12s to the head phone. i was little bit confused about the fft and its uses help me to sort out this problem.

in the audio codec  if i take the sterio input signal and output through the speaker only the noise is coming no audio data what configuration i want to set to hear the the audio data in to the speaker real time.by simply runing the sterio in to head phone out no data is available

with regards

seeni

 

  • 0
    TI__Mastermind 30140 points

    Hi Seeni,

    Sorry for the delay.

    Have you seen the FFT coprocessor documentation?

    The FFT coprocessor is not supported by the Chip Support Library today, but it will work with CSL.

    You need to create the data structures and call the ROM routines shown in the document. See Section 4 HWAFFT Software Interface:

    hwafft_br and hwafft_1024pts with the correct parameters will compute the FFT.

    Also see the code examples included with the SPRABB6 document.

    Hope this helps,
    Mark

  • 0 in reply to Mark M
    Intellectual 580 points

    hai mark

         i has gone through through the fft coprocessor document is it enough for me to add the rom routine to the linker.cmd  file and taken  the 8 data samples and do the fft hwafft routine and perform 8 point fft after that  i  can  try to  implement the dsplib functions for convolution and fir filter for desired coefficent .if so help me on this dsplib

    with regards

    seeni

     

  • 0 in reply to seeni vasan
    TI__Mastermind 30140 points

    Hi Seeni,

    If you add the addresses of the HWAFFT routines in ROM to your .cmd file and include the .h file, the routines will execute from ROM.

    You need to make sure data formatting matches the description in the SPRABB6 doc - The HWAFFT functions use an Int32 pointer to reference complex vectors. Therefore, each 32-bit element contains the 16-bit real part in the most significant 16 bits, and the 16-bit imaginary part in the least significant 16 bits.

    DSPLIB is downloaded from http://www.ti.com/tool/sprc100

    DSPLIB documentation is here http://www.ti.com/lit/ug/spru422j/spru422j.pdf

    There are many examples in the EXAMPLES directory after downloading DSPLIB.

    Some useful tips (like how to rebuild DSPLIB) on the DSPLIB wiki - http://processors.wiki.ti.com/index.php/DSPLIB

    To generate coefficients, I use matlab and the Fixed-Point Toolbox with some formatting.

    Hope this helps,
    Mark