#include <Wire.h>

#define LED_TX_PIN 0 // Pin del LED conectado al TX
#define LED_RX_PIN 1 // Pin del LED conectado al RX

void setup() {
  pinMode(LED_TX_PIN, OUTPUT);
  pinMode(LED_RX_PIN, OUTPUT);

  Wire.begin(8); 
  Wire.onReceive(receiveEvent);
}

void loop() {

}

void receiveEvent(int howMany) {
  while (Wire.available()) {
    char c = Wire.read();
    switch (c) {
      case 'T':
        digitalWrite(LED_TX_PIN, !digitalRead(LED_TX_PIN));
        break;
      case 'R':
        digitalWrite(LED_RX_PIN, !digitalRead(LED_RX_PIN));
        break;
    }
  }
}