Hi,I tried to program the AD9914 DDS with the parallel programming mode. I made the following procedures but cannot see any output in the spectrum analyzer.0- I reset the board by sending an active high pulse on the RST pin and change it to zero.1- I set the F[3:0] = 0000 to select the parallel interface.2- I set the D[31:0] = 0x 00 04 0A 02 to select the 0A parallel address, set as 04 to enable the PLL and set this parameter in write mode as wr is active low.3- I set the D[31:0] = 0x 00 01 03 02 to calibrate the VCO4- I set the D[31:0] = 0x 00 01 0F 02 to calibrate the DAC.5- I change the F[3:0] = 0010 and set the D[31:0] = FTW and change the IO_UPDATE as 1.I suspect I cannot set the appropriate values to the registers because I cannot see anything on the SYNC_CLK with the PLL enable.Can you help me with this issue?
I 'm able to read the default parameters of the registers with the parallel programming mode. But I cannot write to the values.
here is a screen shot what is happening in the board. Any guess why this would happen.
Are you referring to the data signals after the yellow line? I think the wr signal wasn't enabled since they are triggered at low logic. In your snapshot, the wr was in high state, of which wr should be triggered at low logic.
hi, could you please have a look at this thread(https://ez.analog.com/dds/f/q-a/115319/ad9959-phase-precision-degradation)? thanks very much.