WorkingESPmaster

#include <Wire.h>
//#define I2C_SLAVE_1_ADDR  1
#define I2C_SLAVE_2_ADDR  2

void setup() {
  Wire.begin(); // join i2c bus (address optional for master)
  Serial.begin(115200);
  Serial.print("Ready");
}

char x = 0;

void loop() {

      Wire.beginTransmission(2);
      Wire.write('3');
      Wire.endTransmission();
      delay(1000);

      Wire.beginTransmission(2);
      Wire.write('2');
      Wire.endTransmission();
      delay(1000);

      Wire.beginTransmission(2);
      Wire.write('1');
      Wire.endTransmission();
      delay(1000);

      Wire.beginTransmission(2);
      Wire.write('0');
      Wire.endTransmission();
      delay(1000);
}