Arduino Serial Ports

UART0 is the default serial port which is used for serial programming.

Some arduino’s have more than one serial port and these are called Serial1, Serial2, etc

Setup Serial Port

  //----- SETUP SERIAL PORT -----
    ;           //Leonardo/Micro should wait for serial init




  Serial.begin(9600, SERIAL_8N2);    //SERIAL_8E1, SERIAL_8O1, etc

Sending ASCII Text

  Serial.print("Hello");        //Write string no new line
  Serial.println(my_variable);  //Write a value with line break at end

Sending Variables As ASCII

    Serial.print(MyVariable, DEC);     //int value
    Serial.print(MyVariable, HEX);    //hex value
    Serial.println(1.23456, 2)       //Limit decimal places (gives "1.23")

Others see here.

Write Binary Data


Receive Binary Data

  int DataRx;
  if (Serial.available() > 0)    //Gets the number of bytes available for reading from the serial port (buffer holds up to 64 bytes)
    DataRx =;      //Read next byte (returns -1 if no data available)
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