#include <ESP8266WiFi.
h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <WiFiManager.h> // Wi-Fi Manager Library
// === Blynk Credentials ===
#define BLYNK_AUTH_TOKEN "OE4uEpVBopIfPSIcSiayGrnRNzWrGaIh"
#define BLYNK_TEMPLATE_ID "TMPL241NE-FxW"
#define BLYNK_TEMPLATE_NAME "Gas detector dashboard "
#include <BlynkSimpleEsp8266.h>
#include <ESP8266HTTPClient.h>
// === OLED ===
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);
#define MQ6_PIN A0
#define buzzer D5
String name = "LPG/Butane Detector";
// Gas level thresholds in PPM
const int SAFE_LEVEL = 600; // Clean air
const int WARNING_LEVEL = 1000; // Mild leak
const int DANGER_LEVEL = 2000; // Serious leak
unsigned long warmUpStartTime;
const unsigned long warmUpDuration = 60000; // 1 minute warm-up
WiFiManager wm; // Initialize WiFiManager
char auth[] = BLYNK_AUTH_TOKEN;
// === IFTTT Webhook ===
const String IFTTT_KEY = "mHGMCjmy3HmxEw8Xt371CNughQraAWPDnyFSDfilKVS";
const String IFTTT_EVENT = "gas_alert";
// Gas level categories for IFTTT logic
enum GasLevelCategory { LEVEL_SAFE, LEVEL_DETECTED, LEVEL_WARNING, LEVEL_DANGER };
GasLevelCategory lastLevel = LEVEL_SAFE;
void setup() {
WiFi.mode(WIFI_STA); // explicitly set mode, esp defaults to STA+AP
Serial.begin(115200);
pinMode(buzzer, OUTPUT);
digitalWrite(buzzer, LOW);
if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
Serial.println(F("SSD1306 allocation failed"));
while (true); // Halt if display fails to initialize
}
// Show "Starting AP Mode..." on OLED
display.clearDisplay();
display.setTextSize(1);
display.setTextColor(WHITE);
display.setCursor(10, 0);
display.println("Welcome, Starting up...");
display.display();
WiFi.mode(WIFI_STA);
delay(500);
WiFi.hostname("GAS DETECTOR");
wm.setConfigPortalBlocking(false);
//wm.setConfigPortalTimeout(60);
if(wm.autoConnect("GAS || CONFIG PORTAL")){
Serial.println("connected...yeey :)");
}
else {
Serial.println("Configportal running");
}
Blynk.config(auth);
Blynk.connect();
// Once the Wi-Fi configuration is done, show the appropriate message
display.clearDisplay();
display.setTextSize(1);
display.setTextColor(WHITE);
display.setCursor(10, 0);
display.println("OTA Configured!");
display.display();
warmUpStartTime = millis(); // Track the start of the warm-up phase
display.clearDisplay();
printTitle(); // Display title and initialize screen
display.display();
}
void loop() {
wm.process(); // Handle WiFiManager process
Blynk.run();
int rawVal = analogRead(MQ6_PIN); // Read MQ6 sensor value
int ppm = map(rawVal, 0, 1023, 0, 10000); // Map value to PPM (approximate)
// Print raw value and PPM to Serial Monitor for debugging
Serial.print("Raw: ");
Serial.print(rawVal);
Serial.print(" | Approx PPM: ");
Serial.println(ppm);
// Clear the display and re-print title
display.clearDisplay();
printTitle();
unsigned long currentTime = millis();
if (currentTime - warmUpStartTime < warmUpDuration) { // Warm-up phase
printWarming(ppm);
digitalWrite(buzzer, LOW); // No alarm during warm-up
} else { // After warm-up phase
printGasValue(ppm);
printGasLevel(ppm);
updateBlynk(ppm); // Only send ppm value to Blynk
sendIFTTT(ppm); // Send IFTTT alerts if gas level changes
}
display.display(); // Update display
delay(500); // Small delay for display refresh
}
// === Display Functions ===
void printTitle() {
display.setTextSize(1);
display.setTextColor(WHITE);
display.setCursor(22, 0);
display.println("Gas Leak Detector");
display.setCursor(5, 15);
display.println(name);
}
void printWarming(int ppm) {
display.setTextSize(1);
display.setCursor(0, 35);
display.println("Warming up...");
display.setCursor(0, 50);
display.print("Sensor: ");
display.print(ppm);
display.print(" ppm");
}
void printGasValue(int ppm) {
display.setTextSize(2);
display.setCursor(20, 25);
display.print(ppm);
display.print(" ppm");
}
void printGasLevel(int ppm) {
display.setTextSize(1);
display.setCursor(10, 55);
if (ppm < SAFE_LEVEL) {
display.println("Air is clean.");
digitalWrite(buzzer, LOW); // No alarm for safe levels
} else if (ppm < WARNING_LEVEL) {
display.println("Gas Detected!");
beepBuzzer(); // Short beep for detected gas
} else if (ppm < DANGER_LEVEL) {
display.println("Warning! Gas High");
beepBuzzer(); // Short beep for warning levels
} else {
display.println("DANGER! Gas Leak!");
continuousBeep(); // Continuous beep for dangerous levels
}
}
// === Buzzer Functions ===
void beepBuzzer() {
digitalWrite(buzzer, HIGH);
delay(100); // Short beep
digitalWrite(buzzer, LOW);
}
void continuousBeep() {
digitalWrite(buzzer, HIGH); // Continuous beep
}
// === Blynk Update ===
void updateBlynk(int ppm) {
Blynk.virtualWrite(V0, ppm);
}
// === IFTTT Webhook ===
void sendIFTTT(int ppm) {
if (WiFi.status() != WL_CONNECTED) return;
GasLevelCategory currentLevel;
if (ppm < SAFE_LEVEL) {
currentLevel = LEVEL_SAFE;
} else if (ppm < WARNING_LEVEL) {
currentLevel = LEVEL_DETECTED;
} else if (ppm < DANGER_LEVEL) {
currentLevel = LEVEL_WARNING;
} else {
currentLevel = LEVEL_DANGER;
}
if (currentLevel != lastLevel) { // Only send if gas level category changed
HTTPClient http;
String url = "http://maker.ifttt.com/trigger/" + IFTTT_EVENT + "/with/key/" +
IFTTT_KEY;
String value1, value2 = String(ppm), value3;
switch (currentLevel) {
case LEVEL_SAFE:
value1 = "Safe Air";
value3 = "Air is clean. No action needed.";
break;
case LEVEL_DETECTED:
value1 = "Gas Detected!";
value3 = "Ventilate the room.";
break;
case LEVEL_WARNING:
value1 = "WARNING!";
value3 = "Evacuate area. Avoid sparks.";
break;
case LEVEL_DANGER:
value1 = "DANGER!";
value3 = "Major leak! Call emergency services.";
break;
}
String payload = "{\"value1\":\"" + value1 + "\",\"value2\":\"" + value2 +
"\",\"value3\":\"" + value3 + "\"}";
http.begin(url);
http.addHeader("Content-Type", "application/json");
int httpResponseCode = http.POST(payload);
Serial.print("IFTTT Response: ");
Serial.println(httpResponseCode);
http.end();
lastLevel = currentLevel;
}
}
