5.4.23 Project 13.2 IoT Smart Home

1. Description

The IOT smart home connects to the family WiFi through WiFi, and the mobile phone used for operation should also be connected to the same WiFi.

What’s more, the smart home also can connect to the hotspot of the mobile phone. If the connection is successful, the LCD1602 will display the IP address. Using the phone APP to input the corresponding IP for communication is enable to realize the APP control of various functions of the smart home.

2. Test Code

⚠️ \ ATTENTION:\ After opening the code file, you need to modify the WiFi name and passwords that the ESP32 development board needs to connect to. Replace ChinaNet-2.4G-0DF0 and ChinaNet@233 with your own WiFi name and password respectively. You must do this before uploading the code; otherwise, the ESP32 board will not be able to connect to the network.

const char* ssid = "ChinaNet-2.4G-0DF0";  // Enter your own WiFi name
const char* pwd = "ChinaNet@233"; // Enter your own WiFi passwords

⚠️ NOTE: Please ensure that the WiFi name and passwords in the code are the same as the network connected to your computer, mobile phone/tablet, ESP32 development board and router. They must be within the same local area network (WiFi).

⚠️ NOTE: The WiFi must be on a 2.4Ghz frequency; otherwise, the ESP32 cannot connect to WiFi.


#include <Arduino.h>
#ifdef ESP32
#include <WiFi.h>
#elif defined(ESP8266)
#include <ESP8266WiFi.h>
#endif

#include <Wire.h>
#include <Adafruit_NeoPixel.h>
#define LED_PIN    26
#define LED_COUNT 4     // Number of NeoPixels attached
Adafruit_NeoPixel strip(LED_COUNT, LED_PIN, NEO_GRB + NEO_KHZ800);

//Define the variable as the detected value
String request;
const char* ssid = "ChinaNet-2.4G-0DF0";
const char* pwd = "ChinaNet@233";
WiFiServer server(80);  //Initialize the WiFi service

#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27,16,2);

#include <dht11.h>
#define DHT11PIN 17
dht11 DHT11; // Initialize dht11

#include <BuzzerESP32.h>
#define buzzer_pin 25
BuzzerESP32 buzzer(buzzer_pin);   // GPIO25

#define waterPin 34
#define fanPin1 19
#define fanPin2 18
#define led_y 12           // Yellow LED pin definition
#define gasPin 23
#define pyroelectric 14

// Servo channels
int channel_PWM1 = 13;
int channel_PWM2 = 10;
int freq_PWM = 50;
int resolution_PWM = 10;
const int PWM_Pin1 = 5;
const int PWM_Pin2 = 13;

String dataBuffer = "4095,0,0,32,65";

int Rainwater, gas, pir, t, h;  //Define variables
unsigned long prevTask = 0;

void setup() {
  Serial.begin(9600);
  //Connect to WiFi
  WiFi.begin(ssid, pwd);
  //Determine whether it is connected
  Serial.println("Connecting to WiFi...");
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.print(".");
  }
  delay(1000);
  //The serial monitor will display the name and IP address of the wireless network
  Serial.println("Connected to WiFi");
  Serial.print("WiFi NAME:");
  Serial.println(ssid);
  Serial.print("IP:");
  Serial.println(WiFi.localIP());

  //Initialize LCD
  lcd.init();
  //Turn on the LCD backlight
  lcd.backlight();
  //lcd.noBacklight();
  lcd.clear();
  //Set the position of the cursor
  lcd.setCursor(0, 0);
  //LCD printing
  lcd.print("IP:");
  //Set the position of the cursor
  lcd.setCursor(0, 1);
  //LCD printing
  lcd.print(WiFi.localIP());

  pinMode(led_y, OUTPUT);
  pinMode(fanPin1, OUTPUT);
  pinMode(fanPin2, OUTPUT);
  pinMode(waterPin, INPUT);

  buzzer.setTimbre(30);                                  // Set timbre
  buzzer.playTone(0,0);                                  // Turn off buzzer

  pinMode(gasPin, INPUT);
  pinMode(pyroelectric, INPUT);

  ledcAttach(PWM_Pin1, freq_PWM, resolution_PWM);
  ledcAttachChannel(PWM_Pin1, freq_PWM, resolution_PWM, channel_PWM1);
  ledcAttach(PWM_Pin2, freq_PWM, resolution_PWM);
  ledcAttachChannel(PWM_Pin2, freq_PWM, resolution_PWM, channel_PWM2);
  ledcWrite(PWM_Pin1, 25);
  delay(500);
  ledcWrite(PWM_Pin2, 25);
  delay(500);
  //Start the service
  server.begin();
}

void loop() {
  //Check whether the client has been connected to the network server
  //When the client establishes a connection with the server, the "server.available()" function returns a WiFiClient object for client-side communication.
  WiFiClient client = server.available();
  if (client) {
    Serial.println("New client connected");
    while (client.connected()) {
      //Determine whether the server sends data
      if (client.available()) {
        request = client.readStringUntil('s');
        Serial.print("Received message: ");
        Serial.println(request);
      }
      //Obtain all sensor data
      getSensorsData();
      //Put all the data into "dataBuffer"
      dataBuffer = "";
      dataBuffer += String(Rainwater);
      dataBuffer += ",";
      dataBuffer += String(gas);
      dataBuffer += ",";
      dataBuffer += String(pir);
      dataBuffer += ",";
      dataBuffer += String(t);
      dataBuffer += ",";
      dataBuffer += String(h);
      //Send the data to the server and then transfer it to the application.
      if (millis() - prevTask >= 1000) {  // Execute every second
        prevTask = millis();
        client.print(dataBuffer);
      }

      delay(500);

      //LED
      if (request == "a") {
        digitalWrite(led_y, HIGH);
      } else if (request == "A") {
        digitalWrite(led_y, LOW);
      }

      //window servo
      if (request == "b") {
        ledcWrite(PWM_Pin1, 100); //The high level of 20ms is approximately 2.5ms, that is, 2.5/20*1024, and the servo rotates at the specified Angle.
        delay(500);
      } else if (request == "B") {
        ledcWrite(PWM_Pin1, 25);  //The high level of 20ms is approximately 0.5ms, that is, 0.5/20*1024, and the servo rotates at the specified Angle.
        delay(500);
      }

      //buzzer plays music
      if (request == "c") {
        birthday();
        buzzer.playTone(0,0);
      } else if (request == "C") {
        buzzer.playTone(0,0);
      }

      //The buzzer sounds
      if (request == "d") {
        buzzer.playTone(392,250);
      } else if (request == "D") {
        buzzer.playTone(0,0);
      }

      //door servo
      if (request == "e") {
        ledcWrite(PWM_Pin2, 120);
        delay(500);
      } else if (request == "E") {
        ledcWrite(PWM_Pin2, 25);
        delay(500);
      }

      //fan
      if (request == "f") {
        digitalWrite(fanPin2, LOW); //pwm = 0
        analogWrite(fanPin1, 100); //LEDC channel 5 is bound to the specified left motor output PWM value as 100.
      } else if (request == "F") {
        digitalWrite(fanPin2, LOW); //pwm = 0
        analogWrite(fanPin1, 0); //LEDC channel 5 is bound to the specified left motor output PWM value as 0.
      }

      //SK6812RGB turns on and off its red light
      if (request == "g") {
        colorWipe(strip.Color(255,   0,   0), 50);
      } else if (request == "G") {
        colorWipe(strip.Color(0,   0,   0), 50);
      }

      //SK6812RGB turns on and off its orange light
      if (request == "h") {
        colorWipe(strip.Color(200,   100,   0), 50);
      } else if (request == "H") {
        colorWipe(strip.Color(0,   0,   0), 50);
      }

      //SK6812RGB turns on and off its yellow light
      if (request == "i") {
        colorWipe(strip.Color(200,   200,   0), 50);
      } else if (request == "I") {
        colorWipe(strip.Color(0,   0,   0), 50);
      }

      //SK6812RGB turns on and off its green light
      if (request == "j") {
        colorWipe(strip.Color(0,   255,   0), 50);
      } else if (request == "J") {
        colorWipe(strip.Color(0,   0,   0), 50);
      }

      //SK6812RGB turns on and off its blue-green light
      if (request == "k") {
        colorWipe(strip.Color(0,   100,   255), 50);
      } else if (request == "K") {
        colorWipe(strip.Color(0,   0,   0), 50);
      }

      //SK6812RGB turns on and off its blue light
      if (request == "l") {
        colorWipe(strip.Color(0,   0,   255), 50);
      } else if (request == "L") {
        colorWipe(strip.Color(0,   0,   0), 50);
      }

      //SK6812RGB turns on and off its purple light
      if (request == "m") {
        colorWipe(strip.Color(100,   0,   255), 50);
      } else if (request == "M") {
        colorWipe(strip.Color(0,   0,   0), 50);
      }

      //SK6812RGB turns on and off its white light
      if (request == "n") {
        colorWipe(strip.Color(255,   255,   255), 50);
      } else if (request == "N") {
        colorWipe(strip.Color(0,   0,   0), 50);
      }

      //SK6812RGB-sfx1
      if (request == "o") {
        rainbow(10);
      } else if (request == "O") {
        colorWipe(strip.Color(0,   0,   0), 50);
      }

      //SK6812RGB-sfx2
      if (request == "p") {
        theaterChaseRainbow(50);
      } else if (request == "P") {
        colorWipe(strip.Color(0,   0,   0), 50);
      }
      request = "";
    }
    Serial.println("Client disconnected");
  }
}

void getSensorsData() {
   //Obtain data
   int chk = DHT11.read(DHT11PIN);
   t = DHT11.temperature;
   h = DHT11.humidity;

   //steam sensor
   Rainwater = analogRead(waterPin); //read steam sensor analog value and assign it to variable Rainwater

   //gas sensor
   gas = digitalRead(gasPin); //read gas sensor analog value and assign it to variable gas

   //PIR motion sensor
   pir = digitalRead(pyroelectric); //read PIR motion sensor analog value and assign it to variable gas
}

//Convert the data into percentages
String dataHandle(int data) {
  // Convert the analog values to percentages
  int percentage = (data / 4095.0) * 100;
  // If the converted percentage is greater than 100, output 10.
  percentage = percentage > 100 ? 100 : percentage;
  // Six characters are used to store a hexadecimal string, with one serving as the terminator
  char hexString[3];
  // Convert the hexadecimal value to a 6-bit hexadecimal string and add leading zeros in front: 0 represents 00, 1 represents 01...
  sprintf(hexString, "%02X", percentage);

  return hexString;
}

void birthday()
{
  buzzer.playTone(294,250);  //The four parameters are frequency, delay, etc
  buzzer.playTone(440,250);
  buzzer.playTone(392,250);
  buzzer.playTone(532,250);
  buzzer.playTone(494,250);
  buzzer.playTone(392,250);
  buzzer.playTone(440,250);
  buzzer.playTone(392,250);
  buzzer.playTone(587,250);
  buzzer.playTone(532,250);
  buzzer.playTone(392,250);
  buzzer.playTone(784,250);
  buzzer.playTone(659,250);
  buzzer.playTone(532,250);
  buzzer.playTone(494,250);
  buzzer.playTone(440,250);
  buzzer.playTone(698,250);
  buzzer.playTone(659,250);
  buzzer.playTone(532,250);
  buzzer.playTone(587,250);
  buzzer.playTone(532,500);
  buzzer.playTone(0,0);  //off
}

void colorWipe(uint32_t color, int wait) {
  for(int i=0; i<strip.numPixels(); i++) { // For each pixel in the strip...
    strip.setPixelColor(i, color);         // Set the color of the pixels (in RAM)
    strip.show();                          // Update the stripe to match
    delay(wait);                           // delay
  }
}

// The rainbow circulates along the entire band. Transfer the delay time (in milliseconds) between frames.
void rainbow(int wait) {
  for(long firstPixelHue = 0; firstPixelHue < 5*65536; firstPixelHue += 256) {
    for(int i=0; i<strip.numPixels(); i++) { // For each pixel in strip...
      int pixelHue = firstPixelHue + (i * 65536L / strip.numPixels());
      strip.setPixelColor(i, strip.gamma32(strip.ColorHSV(pixelHue)));
    }
    strip.show(); // Update strip content
    delay(wait);  // delay
  }
}

// Rainbow-enhanced Marquise-style. Transfer delay time (milliseconds) between frames
void theaterChaseRainbow(int wait) {
  int firstPixelHue = 0;     // The first pixel starts from red (hue 0).
  for(int a=0; a<30; a++) {  // Repeat 30 times...
    for(int b=0; b<3; b++) { // 'b' counts from 0 to 2...
      strip.clear();         // Set all pixels in RAM to 0(off)
      // 'c' is counted starting from 'b' and increments in units of 3...
      for(int c=b; c<strip.numPixels(); c += 3) {
        int      hue   = firstPixelHue + c * 65536L / strip.numPixels();
        uint32_t color = strip.gamma32(strip.ColorHSV(hue)); // color -> RGB
        strip.setPixelColor(c, color); // Set the value of pixel c to color
      }
      strip.show();                // Update strip content
      delay(wait);                 // delay
      firstPixelHue += 65536 / 90; // The color wheel of one cycle exceeds 90 frames
    }
  }
}

3. Test Result

⚠️ Note: The mobile phone or tablet must be connected to the ESP32 development board via the same WiFi. Otherwise, it will not be able to access the control page. Also, when the ESP32 development board uses the WiFi function, it consumes a lot of power. An external DC power supply is required to meet its power demand for operation. If the power demand is not met, the ESP32 board will keep resetting, resulting in the code not running normally.

A. Enter the IP address in the APP (The allocated IP address will be displayed on the LCD1602 or in the serial monitor window of the IDE.)

B. Click “CONNECT” to connect to the IP address.

C. The successful connection is indicated by the word “Connected” popping up. Please pay attention to it.

D. After the IP address is connected, click the corresponding button on the APP interface to control the corresponding sensor module to work.

image71