It seems I cannot ground one of the DAC channels and simultaneously float another DAC channel.
For example if all DAC outputs have some voltage output and then I
try to ground DAC D by writing (DB7-DB0): 00011100 DACs A-C are unaffected, and DAC D is grounded (this is as expected).
If I then write (DB7-DB0): 01101100, DACs A-B are unaffected, DAC C floats, and DAC D returns to the state it had before it was grounded.
If I reverse the order (first send 01101100 then 00011100) DAC D will be grounded and DAC C will have the value it had before I sent either command.
control register writes to float and ground begin with (DB15-DB8): 01110000, and are followed by NOP writes.
Is is possible to have one DAC output grounded and another floating at the same time? If so, how?