SHARC serial port dai interferance

Started by March 10, 2006

Im working with an ADSP-21364 SHARC processor and EZKIT.

I have a problem when trying to integrate two programs that use the serial

My first program is based on the "Block based talkthrough" example,
SPORT0 is used to take audio input from the ADC and SPORT2 is used to output the
processed audio to a DAC.  This stand-alone program functions correctly.

My second program implements a UART receive on serial port 3B, this is
based on the Eng-to-Eng note EE-191.  Bytes are received through DAI pin 5 and
stored in a buffer. This stand-alone program also functions correctly.

My problem comes when combining the two programs.     As the programs
use different
serial ports and different DAI pins I didn\\\\\\\\\\\\\\\'t think there would be
a problem.

However when I combined the programs the audio processing works but the
UART receiver does not. (Some random data received, no correct data).
Through debugging I have traced the problem down to this line in the SRU config:

SRU(DAI_PB_07_O, DAI_PB_13_I);

When this line is commented out the UART receiver functions correctly
but the audio processing program stops outputting audio.

I understand that this SRU config statement is connecting the ADC clk
directly to the DAC clk, why would this interfere with my UART receive program?

Many Thanks,

Ronan O\\\\\\\\\\\\\\\'Malley