I can read/write the SPICONFIG register (and read-back to confirm), but whenever I write to the DACPWDWN register it only ever reads back as 0xFFFF. According to the datasheet the lower 4 bits are R/W. Specifically, I am trying to power-up all of the DAC's by writing 0 to this register but only ever read back 0xFFFF.
For reference, my configuration steps are:
1) Hold the RST signal low on powerup (for several seconds), then let it rise.
2) Wait 5ms for power-on delay.
3) Write 0x0804 to SPICONFIG (register 3)
4) Write 0 to GENCONFIG (register 4)
5) Write 0 to DACPWDWN (register 9) <—— this reads back as 0xFFFF
6) Write 0x7777 to DACRANGE (register 10)
Any ideas on what I'm doing wrong?
