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This example is for Wiring version 1.0 build 0100+. If you have a previous version, use the examples included with your software. If you see any errors or have comments, please let us know.

Simple ReadWrite
Read data from the serial port and echoes it back to the serial monitor

    char val;                   // to read the char

    void setup()
    {
      Serial.begin(9600);
    }

    void loop()
    {
      if (Serial.available())   // if data available
      {
        val = Serial.read();    // read data
        Serial.print(val);      // print it back
      }
      delay(100);               // wait 100ms for next read
    }