I'm testing a AD7763 now. I powered AD7763 , provided MCLK=20MHz and set RESET=1 SYNC = 1. I think that , without any other configerations, the AD7763 should works and have pulse on DRDY and other control pins. However, I find out that DRDY and FSO are both 0, SCO = 20MHz(which is correct) and SDL is 1 (which is also correct).
I don't know why DRDY and FSO are both 0. At least they should be 1. Do they need pullup res? Or should I do any other configerations? Thank you for you time.