GSM MKR 1400 Serial comm with Arduino Nano

[gordonbm]

Hello,

I'm working on a project to remotely start 2 pumps when sending a message to the MKR.
Now I have a Nano at each pump and using them as 'slaves'.
The MKR is the master which is sending the commands to the Nanos. I've bought HC12 for RF communication but I can't get it to work.
I understand that I cannot use the SofwareSerial library in the MKR.

Is there any way to communicate with the HC12 module from and to the Nano's and the MKR GSM 1400?

[horace]

the MKR series has a hardware serial port on pins 13 Rx and 14Tx
this is a program I used to test a MKRFOX serial communications

// Arduino MKRFOX hardware serial1 test

// NOTE: MKRFOX uses 3.3V logic 
// - if commected to UNO 5V logic use a voltage divider 2.2K to ground 1K to UNO Tx

// MKRFOX pin 14 is TX
// MKRFOX pin 13 is Rx
// for loopback test connect pin 13 to pin 14

void setup() {
  Serial.begin(115200);   // initialise serial monitor port
  while (!Serial) {
      ; // wait for serial port to connect. Needed for native USB port only
    }  
  Serial1.begin(9600);  // initialise Serial1
  Serial.println();
  Serial.write("Arduino MKRFOX Serial1 test -  for loopback test connect pin 13 to pin 14\n");
}

void loop() {
  if (Serial1.available())        // read from Serial1 output to Serial
    Serial.write(Serial1.read());
  if (Serial.available()) {       // read from Serial outut to Serial1
    int inByte = Serial.read();
    //Serial.write(inByte);     // local echo if required
    Serial1.write(inByte);
  }
}

note that the Nano uses 5V logic the MKR is 3.3V - use a potential divider on the Nano Tx to MKR Rx