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Help with understanding pinout on circuit board Answered

I'm an HVAC technician and at school they had a bunch of Carrier EMI thermostats that connect to a router with a module. I'm pretty tech-savvy, but I'm not the greatest when it comes to wireless technology. On the board there are spots labeled: Tx, Rx, A2D2, GNDs, GNDp, and 12vdc. Then there are another 2 labeled OAT and OATC. What do these all mean? All I know is that Tx and Rx are transmitting and receiving. Any help is much appreciated.


I think oat and oat stand for outdoor ambient temperature (maybe thermometer), and outdoor ambient temperature control

GND and 12 volt is ground and 12 volts source. GNDp is PLL ground signal line and i guess GNDs is just common ground.

Makes sense to me, I never heard of PLL before

I just came across a page that's saying the thermostat connects to the internet via a 2-way paging module.

Got a reference to the installation manual ?

Unfortunately no, all I have is the module and the thermostat. I even called carrier and they wouldn't help me out.