I'm using an AD9222, and my goal is to program each on-chip ADC in order to test my connection between the AD9222 and my FPGA. So for each ADC I've to set the "Output Test Mode" register.
I read in the AN877 that : During a write process, more than one device may be written at a time by setting multiple bits in these registers high that correspond to the ADC channels to be written. (page 9).
My problem is that I'm unable to find any information on the sequence I've to send (via SPI) to the AD9222 to program the 8 "Output Test Mode" registers after indexing (reg. 0x04 = x0F & reg. 0x05 = x0F) all my registers at once.