#include <Wire.h>

void setup() {
  Serial.begin(9600);
  
  // Start the I2C Bus as Primary
  Wire.begin();
}

void loop() {
  
  if (Serial.available() > 0) {
    uint8_t inByte = Serial.read();    
    Wire.beginTransmission(7); 
    Wire.write(inByte);    
    Wire.endTransmission();  
  }
}