I am fist time using this DAC chip for a project. I have the DAC38RF8xEVM demo board and UI software work with it very well. I notice the Reset button in the UI will play important role to reset the DAC to a state to program further through SPI. My observation is after toggle that reset button in the software, the SPI register is set/enabled then I can write to register 1 (IO_CONFIG) to set SPI to 4 pin interface mode and can verify from a logic analyzer to prove it. The logic behind this Reset toggle should be as described in one of the application note n the datasheet of DAC38RF8x, as:
1. Pull TXENBLE low(I ground it ); 2. Pull TRSTB low(I ground it as I go use it for JTAG); 3. Toggle RESETB(I push then release the hardware Reset button on the board).
Then after that I expect this will do the same job as the UI software toggle reset button and work for my SPI (my spi master connect to that DAC38RF8x chip), but unfortunately I did not see it work, as my SPI write register 1 with 0x3080, did not set the SPI to be 4 pin mode.
Appreciate if you can find anything still wrong to initialize the DAC to bring it to the state can write register and read it back.
Thanks,
