I have a question about operation of I/O UPDATE for AD9957.
In the lower left of datasheet(rev.C) P.47, it's described follows.
The I/O update can either be sent after each communication cycle or when
all serial operations are complete.
It seems that I can configure AD9957 correctly by one I/O UPDATE pulse after all SPI operation.
But AD9957 does not work when I send I/O UPDATE after sending all register data.
(AD9957 works well when I send I/O UPDATE after each communication cycle.)
I am sending the data in sequence of reg00 to reg19 .
Do I need send the data according to a rule of sequence of register if I send "I/O UPDATE" after all communication cycle ?
edited this message, ysuzuki