So I'm working with an AD5593R chip, which I don't expect anyone to have specific experience with, but I'm hoping there might be a general principle which I can apply.
Basically there's a control register that lets you set which of its 8 pins are GPIO output, and a separate register that lets you set which of its 8 pins are GPIO input. This confuses me slightly.
What if I set them all to 1 in both registers? Are they all output and input at the same time? Or does whatever I set most recently override the other?
I mean, what about the control register that dictates which are DAC pins? What if I try to make them all GPIO in, GPIO out, and DAC simultaneously?
How does this sort of thing usually work? The datasheet does not make it clear.
I mean, I'm not even sure what happens if I tell set all the bits to 0 in all those registers-- then what mode are the pins left in?