WOKWI MQTT&Node-Red (Hello & LED)2

 WOKWI MQTT&Node-Red (Hello & LED)2

使用broker.mqtt-dashboard.com:1883 Broker

Node-red程式

[{"id":"65c9291b678a7fe2","type":"ui_button","z":"b7407e6e7f998627","name":"","group":"5144f4dd267bd26c","order":2,"width":0,"height":0,"passthru":false,"label":"ON","tooltip":"","color":"","bgcolor":"","className":"","icon":"","payload":"on","payloadType":"str","topic":"topic","topicType":"msg","x":270,"y":140,"wires":[["942c6d647680c36c","a8005058e1f66d3a"]]},{"id":"a9165405803b4d06","type":"ui_button","z":"b7407e6e7f998627","name":"","group":"5144f4dd267bd26c","order":4,"width":0,"height":0,"passthru":false,"label":"OFF","tooltip":"","color":"","bgcolor":"","className":"","icon":"","payload":"off","payloadType":"str","topic":"topic","topicType":"msg","x":270,"y":200,"wires":[["942c6d647680c36c","a8005058e1f66d3a"]]},{"id":"942c6d647680c36c","type":"mqtt out","z":"b7407e6e7f998627","name":"LED_control","topic":"alex9ufo/led","qos":"1","retain":"true","respTopic":"","contentType":"","userProps":"","correl":"","expiry":"","broker":"81c048e3.19d648","x":470,"y":180,"wires":[]},{"id":"b93a4b5ca566c65b","type":"mqtt in","z":"b7407e6e7f998627","name":"Hello","topic":"alex9ufo/hello","qos":"0","datatype":"auto-detect","broker":"81c048e3.19d648","nl":false,"rap":true,"rh":0,"inputs":0,"x":270,"y":280,"wires":[["e855db5b2a1f5de2","6ca497bb7dc10aaa"]]},{"id":"e855db5b2a1f5de2","type":"ui_text","z":"b7407e6e7f998627","group":"8ee67a2c0d1061e6","order":1,"width":0,"height":0,"name":"訂閱的訊息","label":"訂閱的訊息","format":"{{msg.payload}}","layout":"row-spread","className":"","x":490,"y":280,"wires":[]},{"id":"a8005058e1f66d3a","type":"debug","z":"b7407e6e7f998627","name":"debug 303","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":470,"y":120,"wires":[]},{"id":"6ca497bb7dc10aaa","type":"debug","z":"b7407e6e7f998627","name":"debug 304","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":490,"y":320,"wires":[]},{"id":"5144f4dd267bd26c","type":"ui_group","name":"LED Control2","tab":"f304c5db6c1258cc","order":5,"disp":true,"width":"6","collapse":false,"className":""},{"id":"81c048e3.19d648","type":"mqtt-broker","broker":"broker.mqtt-dashboard.com","port":"1883","clientid":"","autoConnect":true,"usetls":false,"protocolVersion":4,"keepalive":15,"cleansession":true,"birthQos":"0","willQos":"0","credentials":{}},{"id":"8ee67a2c0d1061e6","type":"ui_group","name":"TEXT","tab":"f304c5db6c1258cc","order":4,"disp":true,"width":"6","collapse":false,"className":""},{"id":"f304c5db6c1258cc","type":"ui_tab","name":"WOKWI_DHT22","icon":"dashboard","order":127,"disabled":false,"hidden":false}]

wokwi程式

#include <ArduinoMqttClient.h>

#include <WiFi.h>

///////please enter your sensitive data in the Secret tab/arduino_secrets.h

char ssid[] =  "Wokwi-GUEST"; // your network SSID (name)

char pass[] =  "" ;           // your network password (use for WPA, or use as key for WEP)

WiFiClient wifiClient;

MqttClient mqttClient(wifiClient);

//const char broker[] = "test.mosquitto.org";

const char broker[] = "broker.mqtt-dashboard.com";

int        port     = 1883;

const char Pubtopic1[]  = "alex9ufo/hello";

const char Subtopic2[]  = "alex9ufo/led";

const char willTopic[] = "alex9ufo/Starting";

//set interval for sending messages (milliseconds)

const long interval = 4000;

unsigned long previousMillis = 0;

int count = 0;

const int LED = 2;

char msg[50];

int value = 0;

//=======================================================================

void onMqttMessage(int messageSize) {

  // we received a message, print out the topic and contents

  Serial.println("Received a message with topic '");

  Serial.print(mqttClient.messageTopic());

  Serial.print("', length ");

  Serial.print(messageSize);

  Serial.println(" bytes:");

  String Topic= mqttClient.messageTopic();

  String message="";

  // use the Stream interface to print the contents

  while (mqttClient.available()) {

    //Serial.print((char)mqttClient.read());

    message += (char)mqttClient.read();

  }

  Serial.println(message);

  message.trim();

  Topic.trim();

  if (Topic=="alex9ufo/led") {

    if (message == "on") {

      digitalWrite(LED, LOW);  // Turn on the LED

      Serial.print("LED = on ");

    }

    if (message == "off" ) {

      digitalWrite(LED, HIGH); // Turn off the LED

      Serial.print("LED = off ");

    }

  }

  Serial.println();

  Serial.println();

}

//=======================================================================

//副程式  setup wifi

void setup_wifi() {

  delay(10);

  // We start by connecting to a WiFi network

  Serial.println();

  Serial.print("Connecting to ");

  Serial.println(ssid);     //print ssid

  WiFi.begin(ssid, pass);  //初始化WiFi 函式庫並回傳目前的網路狀態

  while (WiFi.status() != WL_CONNECTED) {

    delay(500);

    Serial.print(".");

  }   //假設 wifi 未連接 show ………

  Serial.println("");

  Serial.println("WiFi connected");

  Serial.println("IP address: ");

  Serial.println(WiFi.localIP());

}  

//=======================================================================

void setup() {

  //Initialize serial and wait for port to open:

  Serial.begin(115200);

  pinMode(LED, OUTPUT);     // Initialize the BUILTIN_LED pin as an output

  Serial.begin(115200);   // Initialize serial communications with the PC

  while (!Serial);    // Do nothing if no serial port is opened (added for Arduinos based on ATMEGA32U4)

 

  setup_wifi();

  Serial.println("You're connected to the network");

  Serial.println();

 

  String willPayload = "ESP32 Start working....!";

  bool willRetain = true;

  int willQos = 1;

  mqttClient.beginWill(willTopic, willPayload.length(), willRetain, willQos);

  mqttClient.print(willPayload);

  mqttClient.endWill();

  Serial.print("Attempting to connect to the MQTT broker: ");

  Serial.println(broker);

  if (!mqttClient.connect(broker, port)) {

    Serial.print("MQTT connection failed! Error code = ");

    Serial.println(mqttClient.connectError());

    while (1);

  }

  Serial.println("You're connected to the MQTT broker!");

  Serial.println();

  // set the message receive callback

  mqttClient.onMessage(onMqttMessage);

  Serial.print("Subscribing to topic: ");

  Serial.println(Subtopic2);

  // subscribe to a topic

  // the second parameter sets the QoS of the subscription,

  // the the library supports subscribing at QoS 0, 1, or 2

  int subscribeQos = 1;

  mqttClient.subscribe(Subtopic2, subscribeQos);

}

//=======================================================================

void loop() {

  // call poll() regularly to allow the library to send MQTT keep alive which

  // avoids being disconnected by the broker

  mqttClient.poll();

  unsigned long currentMillis = millis();

  if (currentMillis - previousMillis >= interval) {

    // save the last time a message was sent

    previousMillis = currentMillis;

    //record random value from A0, A1 and A2

    ++value;

    snprintf (msg, 75, "hello world #%ld", value);

    Serial.print("Publish message: ");

    Serial.println(msg);

    Serial.print("Sending message to topic: ");

    Serial.println(Pubtopic1);

    Serial.println(msg);

    // send message, the Print interface can be used to set the message contents

    mqttClient.beginMessage(Pubtopic1);

    mqttClient.print(msg);

    mqttClient.endMessage();

    Serial.println();

  }

}

WOKWI MQTT&Node-Red (Hello & LED)

 WOKWI MQTT&Node-Red  (Hello  & LED)

前篇的延伸 (node-red)

https://alex9ufoexploer.blogspot.com/2024/08/mqtt-basic2-wokwi-esp32-mqtt-box.html

const char broker[] = "test.mosquitto.org";

int        port     = 1883;

const char Pubtopic1[]  = "alex9ufo/hello";

const char Subtopic2[]  = "alex9ufo/led";

meaasge H : 亮 , L : 熄

WOKWI程式

#include <ArduinoMqttClient.h>

#include <WiFi.h>

///////please enter your sensitive data in the Secret tab/arduino_secrets.h

char ssid[] =  "Wokwi-GUEST"; // your network SSID (name)

char pass[] =  "" ;           // your network password (use for WPA, or use as key for WEP)

WiFiClient wifiClient;

MqttClient mqttClient(wifiClient);

const char broker[] = "test.mosquitto.org";

int        port     = 1883;

const char Pubtopic1[]  = "alex9ufo/hello";

const char Subtopic2[]  = "alex9ufo/led";

const char willTopic[] = "alex9ufo/Starting";

//set interval for sending messages (milliseconds)

const long interval = 8000;

unsigned long previousMillis = 0;

int count = 0;

const int LED = 2;

char msg[50];

int value = 0;

//=======================================================================

void onMqttMessage(int messageSize) {

  // we received a message, print out the topic and contents

  Serial.println("Received a message with topic '");

  Serial.print(mqttClient.messageTopic());

  Serial.print("', length ");

  Serial.print(messageSize);

  Serial.println(" bytes:");

  String Topic= mqttClient.messageTopic();

  String message="";

  // use the Stream interface to print the contents

  while (mqttClient.available()) {

    //Serial.print((char)mqttClient.read());

    message += (char)mqttClient.read();

  }

  Serial.println(message);

  message.trim();

  Topic.trim();

  if (Topic=="alex9ufo/led") {

    if (message == "H") {

      digitalWrite(LED, LOW);  // Turn on the LED

      Serial.print("LED = on ");

    }

    if (message == "L" ) {

      digitalWrite(LED, HIGH); // Turn off the LED

      Serial.print("LED = off ");

    }

  }

  Serial.println();

  Serial.println();

}

//=======================================================================

//副程式  setup wifi

void setup_wifi() {

  delay(10);

  // We start by connecting to a WiFi network

  Serial.println();

  Serial.print("Connecting to ");

  Serial.println(ssid);     //print ssid

  WiFi.begin(ssid, pass);  //初始化WiFi 函式庫並回傳目前的網路狀態

  while (WiFi.status() != WL_CONNECTED) {

    delay(500);

    Serial.print(".");

  }   //假設 wifi 未連接 show ………

  Serial.println("");

  Serial.println("WiFi connected");

  Serial.println("IP address: ");

  Serial.println(WiFi.localIP());

}  

//=======================================================================

void setup() {

  //Initialize serial and wait for port to open:

  Serial.begin(115200);

  pinMode(LED, OUTPUT);     // Initialize the BUILTIN_LED pin as an output

  Serial.begin(115200);   // Initialize serial communications with the PC

  while (!Serial);    // Do nothing if no serial port is opened (added for Arduinos based on ATMEGA32U4)

 

  setup_wifi();

  Serial.println("You're connected to the network");

  Serial.println();

 

  String willPayload = "ESP32 Start working....!";

  bool willRetain = true;

  int willQos = 1;

  mqttClient.beginWill(willTopic, willPayload.length(), willRetain, willQos);

  mqttClient.print(willPayload);

  mqttClient.endWill();

  Serial.print("Attempting to connect to the MQTT broker: ");

  Serial.println(broker);

  if (!mqttClient.connect(broker, port)) {

    Serial.print("MQTT connection failed! Error code = ");

    Serial.println(mqttClient.connectError());

    while (1);

  }

  Serial.println("You're connected to the MQTT broker!");

  Serial.println();

  // set the message receive callback

  mqttClient.onMessage(onMqttMessage);

  Serial.print("Subscribing to topic: ");

  Serial.println(Subtopic2);

  // subscribe to a topic

  // the second parameter sets the QoS of the subscription,

  // the the library supports subscribing at QoS 0, 1, or 2

  int subscribeQos = 1;

  mqttClient.subscribe(Subtopic2, subscribeQos);

}

//=======================================================================

void loop() {

  // call poll() regularly to allow the library to send MQTT keep alive which

  // avoids being disconnected by the broker

  mqttClient.poll();

  unsigned long currentMillis = millis();

  if (currentMillis - previousMillis >= interval) {

    // save the last time a message was sent

    previousMillis = currentMillis;

    //record random value from A0, A1 and A2

    ++value;

    snprintf (msg, 75, "hello world #%ld", value);

    Serial.print("Publish message: ");

    Serial.println(msg);

    Serial.print("Sending message to topic: ");

    Serial.println(Pubtopic1);

    Serial.println(msg);

    // send message, the Print interface can be used to set the message contents

    mqttClient.beginMessage(Pubtopic1);

    mqttClient.print(msg);

    mqttClient.endMessage();

    Serial.println();

  }

}

WOKWI MQTT&Node-Red (DHT22 & 16*2 LCD & LED)

WOKWI MQTT&Node-Red  (DHT22 & 16*2 LCD & LED)

前一篇的延伸

https://alex9ufoexploer.blogspot.com/2024/10/wokwi-mqtt-dht22-162-lcd-led.html

MQTT相關資料

const char* mqtt_server = "broker.mqttgo.io";

//const char* mqtt_server = "test.mosquitto.org";

const char Pubtopic1[]  = "alex9ufo/temp";

const char Pubtopic2[]  = "alex9ufo/hum";

const char Subtopic1[]  = "alex9ufo/command";

WOKWI程式

#include <WiFi.h>

#include <PubSubClient.h>

#include <LiquidCrystal_I2C.h>

#include "DHTesp.h"

const int DHT_PIN = 15;

const int LED = 2;

DHTesp dhtSensor;

#define I2C_ADDR    0x27

#define LCD_COLUMNS 20

#define LCD_LINES   4

LiquidCrystal_I2C lcd(I2C_ADDR, LCD_COLUMNS, LCD_LINES);

// Update these with values suitable for your network.

const char* ssid =  "Wokwi-GUEST";   // your network SSID (name)

const char* password = "";   // your network password

//const char* mqtt_server = "broker.mqttdashboard.com";// choose your mqtt server

const char* mqtt_server = "broker.mqttgo.io";

//const char* mqtt_server = "test.mosquitto.org";

const char Pubtopic1[]  = "alex9ufo/temp";

const char Pubtopic2[]  = "alex9ufo/hum";

const char Subtopic1[]  = "alex9ufo/command";

WiFiClient espClient;

PubSubClient client(espClient);

long lastMsg = 0;

char msg[50];

int value = 0;

//=========================================================

void callback(char* topic, byte* payload, unsigned int length)

{

  Serial.print("Command from MQTT broker is : [");

  Serial.print(topic);

  Serial.print("]");

  Serial.println();

  Serial.print(" publish data is:");

  lcd.clear();

  String message="";

  {

    for(int i=0;i<length;i++)

    {

      Serial.print((char)payload[i]);  

      message +=(char)payload[i];

      lcd.setCursor(0, 0);

      lcd.print("alex9ufo LCD"); // Start Print text to Line 1

      lcd.setCursor(i, 1);

      lcd.write((char)payload[i]);

    }

  }

 

  //Serial.println(message);

  message.trim();

  if (message == "on") {

      digitalWrite(LED, LOW);  // Turn on the LED

      Serial.print("LED = on ");

  }

  if (message == "off" ) {

      digitalWrite(LED, HIGH); // Turn off the LED

      Serial.print("LED = off ");

  }

  Serial.println();

} //end callback

//=========================================================

void reconnect() {

  // Loop until we're reconnected

  while (!client.connected())

  {

    Serial.print("Attempting MQTT connection...");

    // Create a random client ID

    String clientId = "ESP32Client-";

    clientId += String(random(0xffff), HEX);

    // Attempt to connect

    //if you MQTT broker has clientID,username and password

    //please change following line to    if (client.connect(clientId,userName,passWord))

    if (client.connect(clientId.c_str()))

    {

      Serial.println("connected");

      //once connected to MQTT broker, subscribe command if any

      //client.subscribe("alex9ufo/Command");

      client.subscribe(Subtopic1);

    } else {

      Serial.print("failed, rc=");

      Serial.print(client.state());

      Serial.println(" try again in 5 seconds");

      // Wait 6 seconds before retrying

      delay(6000);

    }

  }

} //end reconnect()

//=========================================================

void setup_wifi() {

   delay(100);

  // We start by connecting to a WiFi network

    Serial.print("Connecting to ");

    Serial.println(ssid);

    WiFi.begin(ssid, password);

    while (WiFi.status() != WL_CONNECTED)

    {

      delay(500);

      Serial.print(".");

    }

  randomSeed(micros());

  Serial.println("");

  Serial.println("WiFi connected");

  Serial.println("IP address: ");

  Serial.println(WiFi.localIP());

}

//=========================================================

void setup() {

  Serial.begin(115200);

 

  pinMode(LED, OUTPUT);     // Initialize the BUILTIN_LED pin as an output

  dhtSensor.setup(DHT_PIN, DHTesp::DHT22);

  setup_wifi();

  client.setServer(mqtt_server, 1883);

 

  // Init

  lcd.init();

  lcd.backlight();

  // Print something

  lcd.setCursor(3, 0);

  lcd.print("Welcome to");

  lcd.setCursor(2, 1);

  lcd.print("lcd display");

  lcd.setCursor(5, 2);

  lcd.print("Simulator");

  lcd.setCursor(7, 3);

  lcd.print("Enjoy!");

}

void loop() {

    if (!client.connected()) {

    reconnect();

  }

  client.setCallback(callback);

  client.loop();

  unsigned long now = millis();

  if (now - lastMsg > 5000) {

    lastMsg = now;

    TempAndHumidity  data = dhtSensor.getTempAndHumidity();

    String temp = String(data.temperature, 2);

    Serial.print("Temperature: ");

    Serial.println(temp);

    client.publish("alex9ufo/temp", temp.c_str());

   

    String hum = String(data.humidity, 1);

    Serial.print("Humidity: ");

    Serial.println(hum);

    client.publish("alex9ufo/hum", hum.c_str());

  }

}

Node-Red程式

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WOKWI MQTT (DHT22 & 16*2 LCD & LED)

 WOKWI  MQTT (DHT22 & 16*2 LCD & LED)

const char* mqtt_server = "broker.mqttgo.io";

const char Pubtopic1[]  = "alex9ufo/temp";

const char Pubtopic2[]  = "alex9ufo/hum";

const char Subtopic1[]  = "alex9ufo/command";

WOKWI程式

#include <WiFi.h>

#include <PubSubClient.h>

#include <LiquidCrystal_I2C.h>

#include "DHTesp.h"

const int DHT_PIN = 15;

const int LED = 2;

DHTesp dhtSensor;

#define I2C_ADDR    0x27

#define LCD_COLUMNS 20

#define LCD_LINES   4

LiquidCrystal_I2C lcd(I2C_ADDR, LCD_COLUMNS, LCD_LINES);

// Update these with values suitable for your network.

const char* ssid =  "Wokwi-GUEST";   // your network SSID (name)

const char* password = "";   // your network password

//const char* mqtt_server = "broker.mqttdashboard.com";// choose your mqtt server

const char* mqtt_server = "broker.mqttgo.io";

//const char* mqtt_server = "test.mosquitto.org";

const char Pubtopic1[]  = "alex9ufo/temp";

const char Pubtopic2[]  = "alex9ufo/hum";

const char Subtopic1[]  = "alex9ufo/command";

WiFiClient espClient;

PubSubClient client(espClient);

long lastMsg = 0;

char msg[50];

int value = 0;

//=========================================================

void callback(char* topic, byte* payload, unsigned int length)

{

  Serial.print("Command from MQTT broker is : [");

  Serial.print(topic);

  Serial.print("]");

  Serial.println();

  Serial.print(" publish data is:");

  lcd.clear();

  String message="";

  {

    for(int i=0;i<length;i++)

    {

      Serial.print((char)payload[i]);  

      message +=(char)payload[i];

      lcd.setCursor(0, 0);

      lcd.print("alex9ufo LCD"); // Start Print text to Line 1

      lcd.setCursor(i, 1);

      lcd.write((char)payload[i]);

    }

  }

 

  //Serial.println(message);

  message.trim();

  if (message == "on") {

      digitalWrite(LED, LOW);  // Turn on the LED

      Serial.print("LED = on ");

  }

  if (message == "off" ) {

      digitalWrite(LED, HIGH); // Turn off the LED

      Serial.print("LED = off ");

  }

  Serial.println();

} //end callback

//=========================================================

void reconnect() {

  // Loop until we're reconnected

  while (!client.connected())

  {

    Serial.print("Attempting MQTT connection...");

    // Create a random client ID

    String clientId = "ESP32Client-";

    clientId += String(random(0xffff), HEX);

    // Attempt to connect

    //if you MQTT broker has clientID,username and password

    //please change following line to    if (client.connect(clientId,userName,passWord))

    if (client.connect(clientId.c_str()))

    {

      Serial.println("connected");

      //once connected to MQTT broker, subscribe command if any

      //client.subscribe("alex9ufo/Command");

      client.subscribe(Subtopic1);

    } else {

      Serial.print("failed, rc=");

      Serial.print(client.state());

      Serial.println(" try again in 5 seconds");

      // Wait 6 seconds before retrying

      delay(6000);

    }

  }

} //end reconnect()

//=========================================================

void setup_wifi() {

   delay(100);

  // We start by connecting to a WiFi network

    Serial.print("Connecting to ");

    Serial.println(ssid);

    WiFi.begin(ssid, password);

    while (WiFi.status() != WL_CONNECTED)

    {

      delay(500);

      Serial.print(".");

    }

  randomSeed(micros());

  Serial.println("");

  Serial.println("WiFi connected");

  Serial.println("IP address: ");

  Serial.println(WiFi.localIP());

}

//=========================================================

void setup() {

  Serial.begin(115200);

 

  pinMode(LED, OUTPUT);     // Initialize the BUILTIN_LED pin as an output

  dhtSensor.setup(DHT_PIN, DHTesp::DHT22);

  setup_wifi();

  client.setServer(mqtt_server, 1883);

 

  // Init

  lcd.init();

  lcd.backlight();

  // Print something

  lcd.setCursor(3, 0);

  lcd.print("Welcome to");

  lcd.setCursor(2, 1);

  lcd.print("lcd display");

  lcd.setCursor(5, 2);

  lcd.print("Simulator");

  lcd.setCursor(7, 3);

  lcd.print("Enjoy!");

}

void loop() {

    if (!client.connected()) {

    reconnect();

  }

  client.setCallback(callback);

  client.loop();

  unsigned long now = millis();

  if (now - lastMsg > 5000) {

    lastMsg = now;

    TempAndHumidity  data = dhtSensor.getTempAndHumidity();

    String temp = String(data.temperature, 2);

    Serial.print("Temperature: ");

    Serial.println(temp);

    client.publish("alex9ufo/temp", temp.c_str());

   

    String hum = String(data.humidity, 1);

    Serial.print("Humidity: ");

    Serial.println(hum);

    client.publish("alex9ufo/hum", hum.c_str());

  }

}

數位媒體課程

數位媒體課程

源自於 嘉義縣立永慶高級中學

https://www.ycsh.cyc.edu.tw/modules/tad_web/news.php?WebID=2&NewsID=16

數位媒體課程

課程名稱：BRICKS 互動式AI數位看板		適合對象：高中(職)學生
單元一	認識Node-RED&MQTT&Opendata&JSON格式	時間：57分		觀賞影片
單元二	Node-RED安裝與功能介紹&LINE Notify	時間：132分		觀賞影片
單元三	Node-RED進階應用與串接MQTT&數位面板	時間：178分		觀賞影片
教學資料下載：PPT簡報   Node-RED軟體下載   程式範例(AQI管理)   LINE Notify   程式範例(MQTT資料傳輸測試)   程式範例(MQTT數位儀表板練習)   練習圖片   MicrosoftEdge下載 備註:程式範例下載請在文字上方按下滑鼠右鍵->>另存連結為...     即可順利下載到電腦中