alex9ufo 聰明人求知心切: 5月 2024

2024年5月18日星期六

ESP32 — MQTT 基本範例 (Node-Red)

ESP32 — MQTT 基本範例

介紹

本課程將展示WOKWI ESP32 模擬的基本MQTT協定使用

每兩秒向主題“alex9ufo/outTopic”發布“hello world”。
訂閱主題“alex9ufo/inTopic”，列印收到的所有訊息。
它假設接收到的有效負載是字串而不是二進位。
如果訂閱的訊息為“ON”，則點亮板載LED。
如果訂閱的訊息為“OFF”，則熄滅板載LED。

準備：

https://wokwi.com/projects/new/esp32 。 wokwi 註冊

Node-RED 安裝
Windows 作業系統源自於https://cumi.co/20221213/
1. 安裝Node.js主程式，下載安裝檔案，執行安裝。
2. 安裝完成之後開啟CMD，確認node及npm版本。
3. CMD輸入 npm install -g --unsafe-perm node-red 安裝Node-RED。
4. CMD輸入node-red啟動Node-RED。
5. 瀏覽器開啟網址http://127.0.0.1:1880。
6. 找到Node-Red設定目錄。
7. CMD輸入 node-red admin hash-pw，使用工具產生密碼加密。
8. 開啟Node-Red設定檔，adminAuth把註解移除，把加密的密碼貼上去。
9. 重新啟用node-red，瀏覽器打開node-red輸入設定之帳號密碼，即可登入。
[Node-RED] dashboard儀表板
node-red-dashboard
http://blog.3dgowl.com/node-red-dashboard%E5%84%80%E8%A1%A8%E6%9D%BF/
node-red-node-sqlite

安裝sqlite節點

因為 Node-RED 中預設未安裝它。

從主選單中，選擇選單->節點管理 (menu->manage palette)，然後使用節點管理配置框，選擇「安裝」標籤。在搜尋欄位中輸入 sqlite，您將看到類似於下面螢幕截圖的結果。

選擇node-red-node-sqlite並選擇安裝。

WOKWI設定：

sketch.ion程式。

#include <WiFi.h>

#include "PubSubClient.h"

// WiFi

char ssid[]="Wokwi-GUEST";

char pass[]="";

// MQTT Broker

const char *mqtt_broker = "broker.mqtt-dashboard.com";//"broker.emqx.io";//Public Broker

const char *mqtt_username = "hivemqtt";

const char *mqtt_password = "public";

const int mqtt_port = 1883;

// App Protcol ---> Port 

const char *topic_publish = "alex9ufo/outTopic";//Topic ESP32 Pusblish

const char *topic_subsrcibe = "alex9ufo/inTopic";//Topic ESp32 Subscribe

WiFiClient hamada;//WIFI Opject

PubSubClient client(hamada);//OOP

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

#define LED 2

bool ledState=false;

unsigned long lastMsg = 0;

#define MSG_BUFFER_SIZE (50)

char msg[MSG_BUFFER_SIZE];

int value = 0;

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 (client.connect(clientId.c_str())) {

      Serial.println("connected");

      // Once connected, publish an announcement...

      client.publish(topic_publish, "Hello world.....");

      client.subscribe(topic_subsrcibe);

    } else {

      Serial.print("failed, rc=");

      Serial.print(client.state());

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

      // Wait 5 seconds before retrying

      delay(5000);

}

}

}

void setup(){

   // Setting LED pin as output

    pinMode(LED, OUTPUT);

    digitalWrite(LED, LOW);  // Turn off the LED initially

    //Open a serial connection to display program results and establish a connection to the Wi-Fi network.

    // Set software serial baud to 115200;

    Serial.begin(115200);

    // Connecting to a Wi-Fi network

    WiFi.begin(ssid, pass);

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

        delay(500);

        Serial.println("Connecting to WiFi..");

}

        Serial.println("Connected to the Wi-Fi network");

    // Utilize PubSubClient to establish a connection with the MQTT broker.

    //connecting to a mqtt broker

    Serial.println("Before Connect MQTT");

    //Broker Configuration 

    client.setServer(mqtt_broker, mqtt_port);

   while (!client.connected()) {

        String client_id = "esp32-client-";

        client_id =client_id+ String(WiFi.macAddress());

        //consloe.log("x"+"y");//xy

        //ESP32-ID -----> esp32-client-macaddress

        //variable.c_str()--->char [] , String

        Serial.printf("The client %s connects to the public MQTT broker\n", client_id.c_str());

        if (client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {

            Serial.println("Public MQTT broker connected");

        } else {

            Serial.print("failed with state ");

            Serial.print(client.state());//1 , 2 , 5

            delay(2000);

}

}

    Serial.println("After Connect MQTT");

    client.publish(topic_publish, "Hello world.....");

    client.subscribe(topic_subsrcibe);

    client.setCallback(callback);

}

void loop() {

  if (!client.connected()) {

    reconnect();

}

  client.loop();

  unsigned long now = millis();

  if (now - lastMsg > 10000) {

    lastMsg = now;

    ++value;

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

    Serial.print("Publish message: ");

    Serial.println(msg);

    client.publish(topic_publish, msg);

}

}

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

  printPayload(topic, message, length);  

}

void printPayload(char* topic, byte* message, unsigned int length) {

  // Printing Received Message

  Serial.print("Message received on topic: ");

  Serial.println(topic);

  String messageTemp;

  for(int i=0; i<length; i+=1) {

    messageTemp += (char)message[i];

}

  if(String(topic) == "alex9ufo/inTopic"){

      Serial.println("alex9ufo/inTopic");

      if(messageTemp=="ON"){

        Serial.println("Led ON");

        digitalWrite(LED,HIGH);

}

      if(messageTemp=="OFF"){

        Serial.println("Led OFF");

        digitalWrite(LED,LOW);

}

}

  Serial.println(messageTemp);

}

diagram.json程式 (電路圖)。

{

  "version": 1,

  "author": "Anonymous maker",

  "editor": "wokwi",

  "parts": [

    { "type": "wokwi-esp32-devkit-v1", "id": "esp", "top": -321.7, "left": -168.2, "attrs": {} },

{

      "type": "wokwi-resistor",

      "id": "r1",

      "top": -225.6,

      "left": 37.85,

      "rotate": 90,

      "attrs": { "value": "1000" }

},

{

      "type": "wokwi-led",

      "id": "led1",

      "top": -310.8,

      "left": 32.6,

      "attrs": { "color": "red" }

}

],

  "connections": [

    [ "esp:TX0", "$serialMonitor:RX", "", [] ],

    [ "esp:RX0", "$serialMonitor:TX", "", [] ],

    [ "led1:C", "esp:GND.1", "black", [ "v0" ] ],

    [ "r1:1", "led1:A", "red", [ "h0" ] ],

    [ "esp:D2", "r1:2", "red", [ "h0" ] ]

],

  "dependencies": {}

}

Library manager --> Project Libaries --> Installed Libraries 。

Node-Red設定：

broker.mqtt-dashboard.com:1883/ws

一、安裝/刪除節點

二、匯入/匯出流程

一、安裝/刪除節點

1.點選右上角的三條橫線下拉選單→「節點管理」(圖1)

2.進入後可以看到已安裝的節點，在此可以禁用或刪除(圖2)

3.被刪除的節點可以再次重新安裝

4.切換至安裝頁面，上方可輸入關鍵字搜尋(圖3)

5.選取要得節點後按下右下角安裝即會進入安裝狀態

特別提醒：安裝和刪除時請確保Node-RED正確運作，切勿關閉或斷線，會造成系統異常而無法開啟和編輯

6.新增的節點將會出現於主畫面左側的節點區

二、匯入/匯出流程

1.點選右上角的三條橫線下拉選單→「匯入、匯出」(圖4)

(1)匯入：將外部檔案放入自己的Node-RED中編輯使用

(2)匯出：將自己的專案轉成jason或文字碼供他人使用

2.點選「匯入」→「匯入所選檔案」→「匯入」(圖5)

特別提醒：若匯入他人資料時本身沒有資料中的結點，Node-RED會無法辨識而跳出警示，需要針對該節點去新增安裝後重新匯入一次，始得正常使用

3.點選「匯出」→「現在的節點」→「下載」(圖6)

(1)按下下載後會匯出jason檔案，需要時再使用匯入功能即可取回資料至Node-RED中

(2)下載旁的「匯出到剪貼簿」會生成文字碼(記事本可開啟)，兩種都可以作為匯出的方式

(3)建議當專案完成後即可匯出檔案作為備份以免遺失

node-red

node-red 程式。

ESP32 — MQTT 基本範例 (MQTT Box)

介紹

本課程將展示WOKWI ESP32 模擬的基本MQTT協定使用。

每兩秒向主題“alex9ufo/outTopic”發布“hello world”。
訂閱主題“alex9ufo/inTopic”，列印收到的所有訊息。
它假設接收到的有效負載是字串而不是二進位。
如果訂閱的訊息為“ON”，則點亮板載LED。
如果訂閱的訊息為“OFF”，則熄滅板載LED。

準備：

https://wokwi.com/projects/new/esp32 。 wokwi 註冊

MQTTbox 下載安裝

WOKWI設定：

sketch.ion程式。

#include <WiFi.h>

#include "PubSubClient.h"

// WiFi

char ssid[]="Wokwi-GUEST";

char pass[]="";

// MQTT Broker

const char *mqtt_broker = "broker.mqtt-dashboard.com";//"broker.emqx.io";//Public Broker

const char *mqtt_username = "hivemqtt";

const char *mqtt_password = "public";

const int mqtt_port = 1883;

// App Protcol ---> Port 

const char *topic_publish = "alex9ufo/outTopic";//Topic ESP32 Pusblish

const char *topic_subsrcibe = "alex9ufo/inTopic";//Topic ESp32 Subscribe

WiFiClient hamada;//WIFI Opject

PubSubClient client(hamada);//OOP

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

#define LED 2

bool ledState=false;

unsigned long lastMsg = 0;

#define MSG_BUFFER_SIZE (50)

char msg[MSG_BUFFER_SIZE];

int value = 0;

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 (client.connect(clientId.c_str())) {

      Serial.println("connected");

      // Once connected, publish an announcement...

      client.publish(topic_publish, "Hello world.....");

      client.subscribe(topic_subsrcibe);

    } else {

      Serial.print("failed, rc=");

      Serial.print(client.state());

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

      // Wait 5 seconds before retrying

      delay(5000);

}

}

}

void setup(){

   // Setting LED pin as output

    pinMode(LED, OUTPUT);

    digitalWrite(LED, LOW);  // Turn off the LED initially

    //Open a serial connection to display program results and establish a connection to the Wi-Fi network.

    // Set software serial baud to 115200;

    Serial.begin(115200);

    // Connecting to a Wi-Fi network

    WiFi.begin(ssid, pass);

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

        delay(500);

        Serial.println("Connecting to WiFi..");

}

        Serial.println("Connected to the Wi-Fi network");

    // Utilize PubSubClient to establish a connection with the MQTT broker.

    //connecting to a mqtt broker

    Serial.println("Before Connect MQTT");

    //Broker Configuration 

    client.setServer(mqtt_broker, mqtt_port);

   while (!client.connected()) {

        String client_id = "esp32-client-";

        client_id =client_id+ String(WiFi.macAddress());

        //consloe.log("x"+"y");//xy

        //ESP32-ID -----> esp32-client-macaddress

        //variable.c_str()--->char [] , String

        Serial.printf("The client %s connects to the public MQTT broker\n", client_id.c_str());

        if (client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {

            Serial.println("Public MQTT broker connected");

        } else {

            Serial.print("failed with state ");

            Serial.print(client.state());//1 , 2 , 5

            delay(2000);

}

}

    Serial.println("After Connect MQTT");

    client.publish(topic_publish, "Hello world.....");

    client.subscribe(topic_subsrcibe);

    client.setCallback(callback);

}

void loop() {

  if (!client.connected()) {

    reconnect();

}

  client.loop();

  unsigned long now = millis();

  if (now - lastMsg > 10000) {

    lastMsg = now;

    ++value;

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

    Serial.print("Publish message: ");

    Serial.println(msg);

    client.publish(topic_publish, msg);

}

}

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

  printPayload(topic, message, length);  

}

void printPayload(char* topic, byte* message, unsigned int length) {

  // Printing Received Message

  Serial.print("Message received on topic: ");

  Serial.println(topic);

  String messageTemp;

  for(int i=0; i<length; i+=1) {

    messageTemp += (char)message[i];

}

  if(String(topic) == "alex9ufo/inTopic"){

      Serial.println("alex9ufo/inTopic");

      if(messageTemp=="ON"){

        Serial.println("Led ON");

        digitalWrite(LED,HIGH);

}

      if(messageTemp=="OFF"){

        Serial.println("Led OFF");

        digitalWrite(LED,LOW);

}

}

  Serial.println(messageTemp);

}

diagram.json程式 (電路圖)。

{

  "version": 1,

  "author": "Anonymous maker",

  "editor": "wokwi",

  "parts": [

    { "type": "wokwi-esp32-devkit-v1", "id": "esp", "top": -321.7, "left": -168.2, "attrs": {} },

{

      "type": "wokwi-resistor",

      "id": "r1",

      "top": -225.6,

      "left": 37.85,

      "rotate": 90,

      "attrs": { "value": "1000" }

},

{

      "type": "wokwi-led",

      "id": "led1",

      "top": -310.8,

      "left": 32.6,

      "attrs": { "color": "red" }

}

],

  "connections": [

    [ "esp:TX0", "$serialMonitor:RX", "", [] ],

    [ "esp:RX0", "$serialMonitor:TX", "", [] ],

    [ "led1:C", "esp:GND.1", "black", [ "v0" ] ],

    [ "r1:1", "led1:A", "red", [ "h0" ] ],

    [ "esp:D2", "r1:2", "red", [ "h0" ] ]

],

  "dependencies": {}

}

Library manager --> Project Libaries --> Installed Libraries 。

MQTTBox設定：

broker.mqtt-dashboard.com:1883/ws

mqtt / tcp

訂閱：文章 (Atom)

2024年5月18日 星期六

ESP32 — MQTT 基本範例 (Node-Red)

介紹

準備：

Windows 作業系統 源自於https://cumi.co/20221213/

node-red-dashboard

node-red-node-sqlite

ESP32 — MQTT 基本範例 (MQTT Box)

介紹

準備：

ESP32 — MQTT 基本範例 (Node-Red)

2024年5月18日星期六

Windows 作業系統源自於https://cumi.co/20221213/