Hi,

The 21469-EZkit Lite board is equipped with an AD1939 codec. It appears that the minimum number of samples is 256. That is rather large with respect to latency between incoming and outgoing signals. In my application the overlap-save algorithm is used, which doubles the length of the FFT vectors to 512. That means that the "small" FFT accelerator cannot be used, only the >=512 version.

Doubling the sample frequency to 96 kHz is no option, because the length of some vectors doubles again and the needed amount of memory does not fit into internal memory.

Is there a method to lower the sample block length to 128 or 64?

Thank you for your response.

Regards,

Reinier

Hi Mahesh,

I agree that NUM_SAMPLES can be changed to a lesser value, but the latency between input and output signal will still be determined by the block length of the AD1939 codec. I did hope that the latency could be reduced, but I now understand that the block length cannot be lowered.

Thank you for your answer.

Regards,

Reinier