thanks Dave.
this is a audio processor application with SHARC 2137x and codec hope AD1937 could do the job. in this application, all ADC input coudl be usesd from difference analog source and including digital port SPIDF/TDM, then Mixer them by DSP, last output driver DAC output.
I just do the a testing directly mode from AN1 analog in and analog DAC out, that is to evaluate the difference channel isolatioin perforance and SNR level.
What I question is chip serial data port coudl be configured "direclt" mode from ADC serial ouput to DAC serial input routing......
so as your answer, that is not ok, and shoudl be done by outsider connecting to both of them, SPDIF loop or connector, right?
thanks again.
Hans