RF 433 Transmitter code

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//This code belongs to the following tutorial video: https://youtu.be/lGR8yVVkEL0
//TRANSMITTER

#include <RH_ASK.h> //RadioHead Amplitude Shift Keying Library

#include <SPI.h> //SPI Library
#include <Wire.h> //Wire Library (I2C)

//ASCII-based OLED library
//Its huge advantage that it is _not_ graphical, so it is using much less memory
#include "SSD1306Ascii.h"
#include "SSD1306AsciiAvrI2c.h"
// 0X3C+SA0 - 0x3C or 0x3D
#define I2C_ADDRESS 0x3C //Address
#define RST_PIN -1 //For OLED with no reset pin

SSD1306AsciiAvrI2c display; //Instantiating a display
RH_ASK rf_driver; //Instatiating a rf_driver for the transmitter

int soundLevel = 0; //variable for the microphone's output
int triggerLevel = 0;
int AVGsoundLevel = 0;
int messageNumber = 0; //1 = triggered, 0 = reset (receiver will wait for a new trigger).
bool triggered = false; //we change this based on the status

//PINS
int microphonePin = A6;
int redLED = 5; // On, when triggered (Triggered)
int greenLED = 6; //on when not triggered (Waiting)
int calibratePin = 2; //to save the triggel level

void setup()
{

  //Initializing the display
  #if RST_PIN >= 0
  display.begin(&Adafruit128x64, I2C_ADDRESS, RST_PIN);
  #else // RST_PIN >= 0
  display.begin(&Adafruit128x64, I2C_ADDRESS);
  #endif // RST_PIN >= 0
  display.setFont(System5x7); //font type
  display.set1X(); //font size (small)
  display.clear();
  //-----------------------------------------------------
  // Initialize ASK Object
  rf_driver.init();
  //-----------------------------------------------------
  //Pins. By default, green will be on.
  pinMode(calibratePin, INPUT_PULLUP); //use the internal pullup
  pinMode(redLED, OUTPUT);
  pinMode(greenLED, OUTPUT);

  digitalWrite(redLED, LOW);
  digitalWrite(greenLED, HIGH);

  attachInterrupt(digitalPinToInterrupt(calibratePin), triggerSoundLevel, RISING); //L -> H, button for calibration

}

void loop()
{
    PrintScreen();    //Print the info on the screen

    MeasureSound();   //Measure the sound

}


void PrintScreen()
{
  display.clear();  //clear display
  display.setCursor(0, 0); //start in the 0 position
  //----------------------------
  display.print("Level: ");
  display.println(AVGsoundLevel);
  display.println();
  //----------------------------
  display.print("Trigger level: ");
  display.println(triggerLevel);
  //----------------------------
  display.println();
  display.print("Status: ");
  if(triggered == false)
  {
    //This gets printed if we do not cross the trigger value
    display.println("Waiting");
    messageNumber = 0; //sends a 0 to the receiver
    SendMessage(messageNumber);
    digitalWrite(redLED, LOW); //only green is on while waiting
    digitalWrite(greenLED, HIGH);

  }
  else
  { //triggered == true
    //This gets printed if we cross the trigger value
    display.println("Triggered");
    messageNumber = 1; //sends a 0 to the receiver
    SendMessage(messageNumber);
    digitalWrite(redLED, HIGH); //red is on when triggered and green is off
    digitalWrite(greenLED, LOW);
  }

}

void MeasureSound()
{
  soundLevel = 0; //Reset it, before filling it up
  AVGsoundLevel = 0; //Reset it, before filling it up

  //Let's measure it for some time and create an average
  for(int i = 0; i < 10; i++)
  {
    soundLevel += analogRead(microphonePin);
    delay(200);
  }
  AVGsoundLevel = soundLevel / 10; //calculate average

  if(AVGsoundLevel < (triggerLevel-100)) //if there is less value, we flip the value of the variable
  {
    triggered = true; //set the bool to true
  }
  else
  {
    triggered = false; //set the bool to false
  }

}

void triggerSoundLevel()
{
  soundLevel = 0;   //Reset it, before filling it up
  triggerLevel = 0; //Reset

  for(int i = 0; i < 10; i++)
  {
    soundLevel += analogRead(microphonePin);
    delay(200);
  }
    triggerLevel = soundLevel / 10;  //calculate average

    soundLevel = 0; //Reset it, again, otherwise, it goes to weird levels in the measure()

}

void SendMessage(int messageNumber)
{
    rf_driver.send((uint8_t *)&messageNumber, sizeof(messageNumber)); //send the message through the RF module
    rf_driver.waitPacketSent();
}