Weather Station and LCD 16x2 - DHT11

1#include <LiquidCrystal.h>
2#include "DHT.h"
3
4LiquidCrystal lcd(7, 8, 9, 10, 11, 12);
5DHT dht(2, DHT11);
6
7int buzzer = 4;      
8int ledVerte = 5;    
9int ledRouge = 6;    
10
11float seuilTemp = 28.0;
12float seuilHum  = 70.0;
13
14unsigned long previousBipMillis = 0;
15const long intervalBip = 500; // bip/pause 0,5s
16bool buzzerState = false;
17
18unsigned long previousLCDMillis = 0;
19const long intervalLCD = 2000; // rafraîchissement LCD 2s
20
21void setup() {
22  lcd.begin(16, 2);
23  dht.begin();
24  pinMode(buzzer, OUTPUT);
25  pinMode(ledVerte, OUTPUT);
26  pinMode(ledRouge, OUTPUT);
27}
28
29void loop() {
30  float humidite = dht.readHumidity();
31  float temperature = dht.readTemperature();
32
33  if (isnan(humidite) || isnan(temperature)) {
34    lcd.clear();
35    lcd.setCursor(0, 0);
36    lcd.print("Erreur capteur");
37    digitalWrite(ledVerte, LOW);
38    digitalWrite(ledRouge, LOW);
39    noTone(buzzer);
40    delay(2000);
41    return;
42  }
43
44  bool alerte = (humidite > seuilHum || temperature > seuilTemp);
45
46  // --- Gestion du buzzer ---
47  unsigned long currentMillis = millis();
48  if (alerte) {
49    digitalWrite(ledVerte, LOW);
50    digitalWrite(ledRouge, HIGH);
51
52    if (currentMillis - previousBipMillis >= intervalBip) {
53      previousBipMillis = currentMillis;
54      buzzerState = !buzzerState;
55      if (buzzerState) {
56        tone(buzzer, 1000); // bip
57      } else {
58        noTone(buzzer);     // pause
59      }
60    }
61  } else {
62    digitalWrite(ledVerte, HIGH);
63    digitalWrite(ledRouge, LOW);
64    noTone(buzzer);
65    previousBipMillis = currentMillis; // reset timer
66  }
67
68  // --- Rafraîchissement LCD toutes les 2s ---
69  if (currentMillis - previousLCDMillis >= intervalLCD) {
70    previousLCDMillis = currentMillis;
71
72    lcd.clear();
73    if (alerte) {
74      lcd.setCursor(0, 0);
75      lcd.print("!!! ALERTE !!!");
76      lcd.setCursor(0, 1);
77      lcd.print("OUVRIR FENETRE!");
78    } else {
79      lcd.setCursor(0, 0);
80      lcd.print("Temp = ");
81      lcd.print(temperature);
82      lcd.print((char)223);
83      lcd.print("C");
84
85      lcd.setCursor(0, 1);
86      lcd.print("Humid = ");
87      lcd.print(humidite);
88      lcd.print("%");
89    }
90  }
91}