jarrod180 / mitsuac Goto Github PK

Did anyone investigate older units that don't have the famous CN105 connector? I was reading that it's alternatively called CN92 on some of the in-ceiling and ducted systems. However the older models (without Inverter) don't have either of these connectors.

I was looking at a PEAD-RP2.5GA ducted unit and it's got a CN90 "Wireless" port meant for IR remote control receivers as well as a connector CN51 called "HA Terminal-A" whose purpose I don't understand. However I've not found a clear output signal, but I wasn't able to check the unit in place while running, just the indoor board on its own, so it might just not have output anything :/

Here's the pins I've been able to identify:

CN90 Wireless
Pin 1: goes to IO pin 20 of the CPU via a 200Ohm resistor, and has a 22k pullup
Pin 2: goes to IO pin 21 of the CPU via a 200Ohm resistor, and has a 22k pullup
Pin 3: GND
Pin 4: not sure
Pin 5: 5V
Pin 6: driven against GND via a NPN transistor (Q71) from IO pin 18 on the CPU
Pin 7: driven against GND via a NPN transistor (Q71) from IO pin 18 on the CPU
Pin 8: not sure
Pin 9: 12-15V unregulated

CN51 HA Terminal-A
Pin 1+3: 12-15V unregulated
Pin 2+4: not sure

so any platform can use a generic c++ library, get rid of any Arduino specific stuff from protocol and make it a portable c++ library. Probably as a master branch and then create the arduino/esp specifics as a downstream branch

would be nice to remove this dependency, the json usage is basic and can probably write a partial json parser using standard c++ to support what we need to do.