SoftwareSerial is used to create an instance of a SoftwareSerial object, whose name you need to provide as in the example below. The inverse_logic argument is optional and defaults to false. See below for more details about what it does. Multiple SoftwareSerial objects may be created, however only one can be active at a given moment.
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
inverse_logic: is used to invert the sense of incoming bits (the default is normal logic). If set, SoftwareSerial treats a LOW (0 volts on the pin, normally) on the Rx pin as a 1-bit (the idle state) and a HIGH (5 volts on the pin, normally) as a 0-bit. It also affects the way that it writes to the Tx pin. Default value is false.
Warning: You should not connect devices which output serial data outside the range that the Arduino can handle, normally 0V to 5V, for a board running at 5V, and 0V to 3.3V for a board running at 3.3V.
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