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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 Slave Sender by Nicholas Zambetti
Demonstrates use of the Wire library Sends data as an I2C/TWI slave device Refer to the "Wire Master Reader" 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(2);                 // join i2c bus with address #2
      Wire.onRequest(requestEvent);  // register event
    }

    void loop()
    {
      delay(100);
    }

    // function that executes whenever data is requested by master
    // this function is registered as an event, see setup()
    void requestEvent()
    {
      Wire.write("hello ");  // respond with message of 6 bytes
                            // as expected by master
    }