Wire.h Library - Arduino

void loop() Wire.beginTransmission(8); // Slave address 8 Wire.write("Hello Slave!"); Wire.endTransmission();

Try the built-in I2C scanner (File → Examples → Wire → Scanner), then hook up a cheap OLED or RTC module. You’ll be amazed at what two wires can do. arduino wire.h library

// Configure sensor (simplified) Wire.beginTransmission(SENSOR_ADDR); Wire.write(0x26); // Control register Wire.write(0xB9); // Active, 128 samples, 2^8mbar max Wire.endTransmission(); delay(100); void loop() Wire

void loop() // Tell sensor to start measurement Wire.beginTransmission(SENSOR_ADDR); Wire.write(0x12); // Pressure data register (MSB) Wire.endTransmission(false); // Repeated start void loop() Wire.beginTransmission(8)

#include <Wire.h> void receiveEvent(int bytes) while(Wire.available()) char c = Wire.read(); Serial.print(c);