A call to SoftwareSerial(rxPin, txPin) creates a new SoftwareSerial object, whose name you need to provide as in the example below. You need to call SoftwareSerial.begin() to enable communication.
- rxPin: the pin on which to receive serial data
- txPin: the pin on which to transmit serial data
#define rxPin 2
#define txPin 3
// set up a new serial port
SoftwareSerial mySerial = SoftwareSerial(rxPin, txPin);