alex9ufo 聰明人求知心切: WOKWI ESP32 DHT22 溫度濕度上下限設定 (MQTT 工具)

WOKWI ESP32 DHT22 溫度濕度上下限設定

溫度下限值：現在與「繼電器 1」處於 row 2。

溫度上限值：現在與「繼電器 3」處於 row 4。

濕度下限值：現在與「繼電器 4」處於 row 6。

濕度上限值：現在與「繼電器 6」處於 row 8。

字體顏色：當繼電器狀態切換為 ON 時，對應的 OFF/ON 字樣會變成紅色。

MQTT BOX

MQTTGO.io

Python+TKinter

ESP32 結合 MQTT 範例主要是實現物聯網數據的發布 (Publish) 和訂閱 (Subscribe)，例如透過 Arduino IDE 寫程式讓 ESP32 連上 WiFi，再連接 EMQX 提供的公開測試 MQTT broker, 範例包括讀取溫濕度感測器 (如 DHT11/DHT22) 將數據發布到特定主題 (Topic)，或接收控制指令並控制 LED RELAY 等，關鍵在於使用 PubSubClient 函式庫與 ESP-IDF 的 ESP-MQTT 範例來處理 TCP/SSL/WebSocket 連線和消息收發。

核心概念

MQTT Broker: 訊息的中介站 (例如 test.mosquitto.org)。
Topic: 訊息的分類主題 (例如 home/livingroom/temperature)。
Publish (發布者): 將感測器數據發送到 Topic。
Subscribe (訂閱者): 訂閱 Topic 接收消息。

參考 https://hackmd.io/@richardychen/IoT_wk15mqtt

Python 程式與 Wokwi Arduino IDE 程式

import tkinter as tk

from tkinter import font

import paho.mqtt.client as mqtt

# --- MQTT 配置 ---

BROKER = "mqttgo.io"

PORT = 1883

TOPICS = {

"temp": "alex9ufo/dht22/temp",

"humi": "alex9ufo/dht22/humi",

}

RELAY_TOPICS = [

"alex9ufo/relay1", "alex9ufo/relay2", "alex9ufo/relay3",

"alex9ufo/relay4", "alex9ufo/relay5", "alex9ufo/relay6"

]

class MQTTApp:

def __init__(self, root):

self.root = root

self.root.title("ESP32 監控系統")

self.root.geometry("700x500")

self.label_font = font.Font(size=12)

self.val_font = font.Font(size=12, weight="bold")

# 變數初始化

self.current_temp = tk.StringVar(value="--")

self.current_humi = tk.StringVar(value="--")

self.mqtt_status = tk.StringVar(value="斷線")

self.relay_status = [tk.StringVar(value="OFF") for _ in range(6)]

self.relay_labels = []

self.setup_ui()

self.client = mqtt.Client()

self.client.on_connect = self.on_connect

self.client.on_message = self.on_message

try:

self.client.connect(BROKER, PORT, 60)

self.client.loop_start()

except:

self.mqtt_status.set("連線失敗")

def setup_ui(self):

# 設定整體網格權重

for i in range(12): self.root.grid_rowconfigure(i, weight=1)

for i in range(4): self.root.grid_columnconfigure(i, weight=1)

# --- 第一行：目前溫濕度 ---

tk.Label(self.root, text="目前溫度:", font=self.label_font).grid(row=0, column=0, sticky="e")

tk.Label(self.root, textvariable=self.current_temp, font=self.val_font, fg="blue", relief="sunken", width=12).grid(row=0, column=1, padx=5)

tk.Label(self.root, text="目前濕度:", font=self.label_font).grid(row=0, column=2, sticky="e")

tk.Label(self.root, textvariable=self.current_humi, font=self.val_font, fg="blue", relief="sunken", width=12).grid(row=0, column=3, padx=5)

# --- 繼電器與設定值佈局 (依圖片位置) ---

pins = ["23", "22", "21", "19", "18", "5"]

# 1. 繼電器1 (23) 與溫度下限值 (Row 2)

tk.Label(self.root, text=f"繼電器1 ({pins[0]})狀態:", font=self.label_font).grid(row=2, column=0, sticky="e")

lbl1 = tk.Label(self.root, textvariable=self.relay_status[0], font=self.val_font, relief="sunken", width=12)

lbl1.grid(row=2, column=1, padx=5); self.relay_labels.append(lbl1)

tk.Label(self.root, text="溫度下限值:", font=self.label_font).grid(row=2, column=2, sticky="e")

self.ent_t_low = tk.Entry(self.root, width=15); self.ent_t_low.insert(0, "20"); self.ent_t_low.grid(row=2, column=3)

# 2. 繼電器2 (22) (Row 3)

tk.Label(self.root, text=f"繼電器2 ({pins[1]})狀態:", font=self.label_font).grid(row=3, column=0, sticky="e")

lbl2 = tk.Label(self.root, textvariable=self.relay_status[1], font=self.val_font, relief="sunken", width=12)

lbl2.grid(row=3, column=1, padx=5); self.relay_labels.append(lbl2)

# 3. 繼電器3 (21) 與溫度上限值 (Row 4)

tk.Label(self.root, text=f"繼電器3 ({pins[2]})狀態:", font=self.label_font).grid(row=4, column=0, sticky="e")

lbl3 = tk.Label(self.root, textvariable=self.relay_status[2], font=self.val_font, relief="sunken", width=12)

lbl3.grid(row=4, column=1, padx=5); self.relay_labels.append(lbl3)

tk.Label(self.root, text="溫度上限值:", font=self.label_font).grid(row=4, column=2, sticky="e")

self.ent_t_high = tk.Entry(self.root, width=15); self.ent_t_high.insert(0, "30"); self.ent_t_high.grid(row=4, column=3)

# --- 中間空行 (Row 5) ---

# 4. 繼電器4 (19) 與濕度下限值 (Row 6)

tk.Label(self.root, text=f"繼電器4 ({pins[3]})狀態:", font=self.label_font).grid(row=6, column=0, sticky="e")

lbl4 = tk.Label(self.root, textvariable=self.relay_status[3], font=self.val_font, relief="sunken", width=12)

lbl4.grid(row=6, column=1, padx=5); self.relay_labels.append(lbl4)

tk.Label(self.root, text="濕度下限值:", font=self.label_font).grid(row=6, column=2, sticky="e")

self.ent_h_low = tk.Entry(self.root, width=15); self.ent_h_low.insert(0, "40"); self.ent_h_low.grid(row=6, column=3)

# 5. 繼電器5 (18) (Row 7)

tk.Label(self.root, text=f"繼電器5 ({pins[4]})狀態:", font=self.label_font).grid(row=7, column=0, sticky="e")

lbl5 = tk.Label(self.root, textvariable=self.relay_status[4], font=self.val_font, relief="sunken", width=12)

lbl5.grid(row=7, column=1, padx=5); self.relay_labels.append(lbl5)

# 6. 繼電器6 (5) 與濕度上限值 (Row 8)

tk.Label(self.root, text=f"繼電器6 ({pins[5]})狀態:", font=self.label_font).grid(row=8, column=0, sticky="e")

lbl6 = tk.Label(self.root, textvariable=self.relay_status[5], font=self.val_font, relief="sunken", width=12)

lbl6.grid(row=8, column=1, padx=5); self.relay_labels.append(lbl6)

tk.Label(self.root, text="濕度上限值:", font=self.label_font).grid(row=8, column=2, sticky="e")

self.ent_h_high = tk.Entry(self.root, width=15); self.ent_h_high.insert(0, "70"); self.ent_h_high.grid(row=8, column=3)

# --- 底部：MQTT 連線狀態 ---

tk.Label(self.root, text="MQTT連線狀態:", font=self.label_font).grid(row=10, column=0, sticky="e")

tk.Label(self.root, textvariable=self.mqtt_status, font=self.val_font, fg="green", relief="sunken", width=12).grid(row=10, column=1, padx=5)

def on_connect(self, client, userdata, flags, rc):

if rc == 0:

self.mqtt_status.set("已連線")

client.subscribe(TOPICS["temp"])

client.subscribe(TOPICS["humi"])

def on_message(self, client, userdata, msg):

try:

val = float(msg.payload.decode())

if msg.topic == TOPICS["temp"]:

self.current_temp.set(f"{val} °C")

self.check_logic(val, "temp")

elif msg.topic == TOPICS["humi"]:

self.current_humi.set(f"{val} %")

self.check_logic(val, "humi")

except: pass

def check_logic(self, current_val, mode):

try:

if mode == "temp":

low, high = float(self.ent_t_low.get()), float(self.ent_t_high.get())

indices = [0, 1, 2]

else:

low, high = float(self.ent_h_low.get()), float(self.ent_h_high.get())

indices = [3, 4, 5]

states = ["OFF", "OFF", "OFF"]

if current_val < low: states[0] = "ON"

elif current_val > high: states[2] = "ON"

else: states[1] = "ON"

for i, idx in enumerate(indices):

self.relay_status[idx].set(states[i])

# 狀態為 ON 時顯示紅色

self.relay_labels[idx].config(fg="red" if states[i] == "ON" else "black")

self.client.publish(RELAY_TOPICS[idx], states[i])

except: pass

if __name__ == "__main__":

root = tk.Tk()

app = MQTTApp(root)

root.mainloop()

WOKWI程式

#include <WiFi.h>
#include <PubSubClient.h>
#include <DHTesp.h>

// --- 配置參數 ---
const char* ssid = "Wokwi-GUEST";     // Wokwi 專用 WiFi
const char* password = "";
const char* mqtt_server = "mqttgo.io";

// 定義接腳
const int DHT_PIN = 15;
const int RELAY_PINS[] = {23, 22, 21, 19, 18, 5};
const char* RELAY_TOPICS[] = {
  "alex9ufo/relay1", "alex9ufo/relay2", "alex9ufo/relay3",
  "alex9ufo/relay4", "alex9ufo/relay5", "alex9ufo/relay6"
};

DHTesp dhtSensor;
WiFiClient espClient;
PubSubClient client(espClient);

unsigned long lastMsg = 0;

void setup_wifi() {
  delay(10);
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);

  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nWiFi connected");
}

// 接收來自 Python (MQTT) 的指令
void callback(char* topic, byte* payload, unsigned int length) {
  String message;
  for (int i = 0; i < length; i++) {
    message += (char)payload[i];
  }
  
  Serial.print("Message arrived [");
  Serial.print(topic);
  Serial.print("] ");
  Serial.println(message);

  // 比對 Topic 並切換對應的繼電器接腳
  for (int i = 0; i < 6; i++) {
    if (String(topic) == RELAY_TOPICS[i]) {
      if (message == "ON") {
        digitalWrite(RELAY_PINS[i], HIGH);
      } else {
        digitalWrite(RELAY_PINS[i], LOW);
      }
    }
  }
}

void reconnect() {
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    String clientId = "ESP32Client-" + String(random(0xffff), HEX);
    if (client.connect(clientId.c_str())) {
      Serial.println("connected");
      // 訂閱所有繼電器 Topic
      for (int i = 0; i < 6; i++) {
        client.subscribe(RELAY_TOPICS[i]);
      }
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}

void setup() {
  Serial.begin(115200);
  
  // 初始化繼電器接腳為輸出
  for (int i = 0; i < 6; i++) {
    pinMode(RELAY_PINS[i], OUTPUT);
    digitalWrite(RELAY_PINS[i], LOW); // 預設關閉
  }

  dhtSensor.setup(DHT_PIN, DHTesp::DHT22);
  setup_wifi();
  client.setServer(mqtt_server, 1883);
  client.setCallback(callback);
}

void loop() {
  if (!client.connected()) {
    reconnect();
  }
  client.loop();

  // 每 2 秒讀取一次溫濕度並上傳
  unsigned long now = millis();
  if (now - lastMsg > 2000) {
    lastMsg = now;
    TempAndHumidity data = dhtSensor.getTempAndHumidity();

    if (isnan(data.temperature) || isnan(data.humidity)) {
      Serial.println("Failed to read from DHT sensor!");
      return;
    }

    // 發布溫度
    client.publish("alex9ufo/dht22/temp", String(data.temperature, 2).c_str());
    // 發布濕度
    client.publish("alex9ufo/dht22/humi", String(data.humidity, 2).c_str());

    Serial.print("Temp: "); Serial.print(data.temperature);
    Serial.print("C, Humi: "); Serial.print(data.humidity); Serial.println("%");
  }
}

alex9ufo 聰明人求知心切

2025年12月24日星期三

WOKWI ESP32 DHT22 溫度濕度上下限設定 (MQTT 工具)

沒有留言:

張貼留言

WOKWI 模擬 MFRC522 RFID Reader + 5個 Tag 發行到MQTT 上

2025年12月24日 星期三

WOKWI ESP32 DHT22 溫度濕度 上下限設定 (MQTT 工具)

沒有留言:

張貼留言

WOKWI 模擬 MFRC522 RFID Reader + 5個 Tag 發行到MQTT 上

2025年12月24日星期三

WOKWI ESP32 DHT22 溫度濕度上下限設定 (MQTT 工具)