Is there a way to set the output voltage for what pinh/pinhigh uses?
Or do I need to turn my pin into a smartpin using one of the DAC modes?
Deleted. See Evan's post below.
It sounds like you are wanting the bitDAC pin mode. It provides a coarse bi-level 4-bit DAC, simply using OUT. Smartpin not used.
BitDAC has bee tested and works well for improved impedance matching with HDMI link drive even up at 350 MHz. Typical pin config would be:
wrpin( pinnum, P_DAC_124R_3V | P_BITDAC | bithigh<<12 | bitlow<<8 )
bithigh and bitlow are 4-bit values, 0..15, that set the OUT's high and low levels respectively.
That's pretty neat -- thanks for that, Evan.
Oh wow, that sounds perfect. Thanks evanh!
Quick followup question: when using the non-smartpin/non-bitDAC output for bit-banged IO, that is the stiffest rail-to-rail drive available, right?
Yes, "FAST" logic drive strength is the strongest, around 20 ohms.
Strongest 3v3 DAC output is 124 ohms.
75 ohm 2 Volt DAC is option too.
The DACs are like a class-A amp though I think, so lots of them enabled will create steady heat in the prop2 and steady draw on the supply.