Reef Angel Forum

Hi guys,
I have an RA+ with salinity and wifi expansion.
I use both ATO ports for float valves, but wish to hook up a third float for skimmer over-flow protection. Since I don't really want to buy the IO module + expansion hub just for 1 input, I though perhaps I could re-purpose one of the dimming ports.

Looking at the schematic the PWM_DAYLIGHT pin is connected to (OC2A/PCINT4)PB4. Would I be able to wire the daylight PWM signal port via the float switch and a resistor to ground and write some custom code to treat it as a general IO? Are there any other easier ways?

Are any other IO pins exposed on the PCB to a pad or connection point? I'm not adverse to soldering onto the PCB in the RA unit, as I see in the schematic there are many unused ports (potentially not broken out from the tiny IC pads though). Any suggestions?

Thanks!

Hummm. The actinic and daylight channels are used inside the relay box.
There is a signal booster inside the relay box to convert the 0-5V to 0-10V.
If you remove the booster, you would use it as a general purpose I/O.
Another option is to use one of the ICSP pins for your purpose.
I hope this helps.