thank you Chris
some part of my problem has been solved. now i can write into registers right after i read data from adc .but some problems didn't solve.if i want to change mux or any other register data(for example changing clock rate on d0),i should repeat the write process many times (for example 10000) that i trust the value write to register.if it is less than 10000 the write value may or may not be successful .and i cant read from registers too.if i try to read a registers value,send back 0x00 value .
thanks for your replay
alireza roozitalab