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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.

Wire Master Writer by Nicholas Zambetti
Demonstrates use of the Wire library Writes data to an I2C/TWI slave device Refer to the "Wire Slave Receiver" example for use with this On Wiring v1 boards the SCL and SDA pins are: 0 and 1 On Wiring S board the SCL and SDA pins are: 8 and 9

    #include <Wire.h>

    void setup()
    {
      Wire.begin();  // join i2c bus (address optional for master)
    }

    byte x = 0;

    void loop()
    {
      Wire.beginTransmission(4);  // transmit to device #4
      Wire.write("x is ");         // sends five bytes
      Wire.write(x);               // sends one byte
      Wire.endTransmission();     // stop transmitting

      x++;
      delay(500);
    }