@y4CdW42Ol8 said: What can i use to create an interrupt to wake a sleeping Arduino? This using your Plant_Moisture_Sensor sketch. A timer (whick my sketch alreay uses) or a change in an interrupt pin, see the Sleeping section on https://www.mysensors.org/download/sensor_api_15#the-full-api and http://playground.arduino.cc/Code/Interrupts

@y4CdW42Ol8 those calls are to the MySensors library . You are in the MySensors forum :-D Starting at https://www.mysensors.org/about/ is the best way to learn about MySensors. The receive sketch is called a gateway. Read the links I posted for you in https://forum.mysensors.org/topic/4093/what-does-a-gateway-do/1 to learn about gateways.

@y4CdW42Ol8 Have a look at the examples as supplied with the mySensors library. Both ways are implemented extensively. The gw.sleep(...) function will be the way to go for the 12 hrs. you'd like to put the sensor asleep. This is used in many examples For waking up with interrupt have a look at the example for the power meter. It wakes up the sensor when an interrupt occurs. Be my guest to find your own way of programming this, but as @mfalkvidd already pointed out: MySensors has its own functions! Good luck, Boozz.

@y4CdW42Ol8 IRQ is not used by MySensors library

Problem Solved! When compiling, you must select Processor: ATmega 328 (3.3v, 8Mhz). Then the Serial Monitor will be fine at 9600 baud with the 3.3v Pro Mini.

@y4CdW42Ol8 said: So in the build example, should the DO pin of the sensor be hooked to D2 of the Arduino? No, D0 on the moisture sensor is connected to D3 on the Arduino. See the wiring instructions: https://www.mysensors.org/build/moisture#wiring-things-up

To put it pretty simply, a gateway is a way to convert and move data from one protocol to another. For example, At some point I am hoping to create a MySensors gateway that will let the MySensors protocol talk to my RCS serial thermostat that runs on an RS485 serial network and uses a protocol written by RCS.

Oh good, Thanks.

https://github.com/mysensors/Arduino/issues/119

@y4CdW42Ol8 Try compiling with SDA instead of A4 and SCL instrad of A5 in the pinmode function. This should make the sketch board independant. And then use the correct pins on each board.