in adf5901+adf4159+adf5904 system,on power,set pin ce=1 0f adf5901,the VREG is at 1.8v and Rset is at 0.62v,and i write data to adf5901,and read data from adf5901,however,the pin dout is always high?my setting is following:
//MUXOUT Control(DB15:DB12)=0001 LOGIC HIGH
//IO LEVEL(B11)=1 3.3V
//Readback Control(B10:5)=000-010 REGISTER 1
#define ADF5901_R3 0x01891843//3.3v
//N Divider to MUXOUT Enable(B21):1 NORMAL OPERATION
// Setting this bit to 0 enables the internal N divider signal to MUXOUT
//Test Bus to ADC(B16):0 Set this bit to 0 for normal operation.
// Setting this bit to 1 connects the analog test bus to the ADC input.
//Test Bus to Pin(B15):0 Setting this bit to 0 sets the ATEST pin to high impedance.
// Setting this bit to 1 connects the analog test bus to the ATEST pin.
//Analog Test Bus(B14:5):0
//#define ADF5901_R4 0x00200004
#define ADF5901_R4 0x00218004