alex9ufo 聰明人求知心切: 2021

2021年12月31日星期五

ESP32 Web Server with Slider & MQTT : Control LED Brightness (PWM)

// Import required libraries

#include <WiFi.h>

#include <AsyncTCP.h>

#include <ESPAsyncWebServer.h>

//================MQTT=====================

#include <PubSubClient.h> //MQTT

// Replace with your network credentials

//const char* ssid = "REPLACE_WITH_YOUR_SSID";

//const char* password = "REPLACE_WITH_YOUR_PASSWORD";

const char* ssid = "TOTOLINK_A3002MU";

const char* password = "24063173";

//================MQTT=====================

const char* mqtt_server = "broker.mqtt-dashboard.com" ; //MQTT

// Set web server port number to 80

const int output = 2;

String sliderValue = "0";

// setting PWM properties

const int freq = 5000;

const int ledChannel = 0;

const int resolution = 8;

const char* PARAM_INPUT = "value";

// Create AsyncWebServer object on port 80

AsyncWebServer server(80);

//================MQTT=====================

WiFiClient espClient;

PubSubClient client(espClient);

long lastMsg = 0;

char msg[50];

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

const char index_html[] PROGMEM = R"rawliteral(

<!DOCTYPE HTML><html>

<head>

<title>ESP Web Server</title>

<style>

html {font-family: Arial; display: inline-block; text-align: center;}

h2 {font-size: 2.3rem;}

p {font-size: 1.9rem;}

body {max-width: 400px; margin:0px auto; padding-bottom: 25px;}

.slider { -webkit-appearance: none; margin: 14px; width: 360px; height: 25px; background: #FFD65C;

outline: none; -webkit-transition: .2s; transition: opacity .2s;}

.slider::-webkit-slider-thumb {-webkit-appearance: none; appearance: none; width: 35px; height: 35px; background: #003249; cursor: pointer;}

.slider::-moz-range-thumb { width: 35px; height: 35px; background: #003249; cursor: pointer; }

</style>

</head>

<body>

<h2>ESP Web Server</h2>

<p><span id="textSliderValue">%SLIDERVALUE%</span></p>

function updateSliderPWM(element) {

var sliderValue = document.getElementById("pwmSlider").value;

document.getElementById("textSliderValue").innerHTML = sliderValue;

console.log(sliderValue);

var xhr = new XMLHttpRequest();

xhr.open("GET", "/slider?value="+sliderValue, true);

xhr.send();

}

</script>

</body>

</html>

)rawliteral";

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

// Replaces placeholder with button section in your web page

String processor(const String& var){

//Serial.println(var);

if (var == "SLIDERVALUE"){

return sliderValue;

}

return String();

}

//================MQTT=====================

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

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

Serial.print(topic);

Serial.print(". Message: ");

String messageTemp;

for (int i = 0; i < length; i++) {

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

messageTemp += (char)message[i];

}

Serial.println();

// Feel free to add more if statements to control more GPIOs with MQTT

// If a message is received on the topic esp32/output, you check if the message is either "on" or "off".

// Changes the output state according to the message

if (String(topic) == "alex9ufo/esp32/slider/input") {

Serial.print("Changing output to ");

sliderValue = messageTemp;

ledcWrite(ledChannel, sliderValue.toInt());

}

loop_mqtt();

}

//================MQTT=====================

void reconnect() {

// Loop until we're reconnected

while (!client.connected()) {

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

// Attempt to connect

if (client.connect("ESP32Client")) {

Serial.println("connected");

// Subscribe

client.subscribe("alex9ufo/esp32/slider/input");

} else {

Serial.print("failed, rc=");

Serial.print(client.state());

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

// Wait 5 seconds before retrying

delay(5000);

}

//================MQTT=====================

void loop_mqtt(){

if (!client.connected()) {

reconnect();

}

client.loop();

long now = millis();

if (now - lastMsg > 5000) {

lastMsg = now;

}

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

void setup(){

// Serial port for debugging purposes

Serial.begin(115200);

// configure LED PWM functionalitites

ledcSetup(ledChannel, freq, resolution);

// attach the channel to the GPIO to be controlled

ledcAttachPin(output, ledChannel);

ledcWrite(ledChannel, sliderValue.toInt());

// Connect to Wi-Fi

WiFi.begin(ssid, password);

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

delay(1000);

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

}

// Print ESP Local IP Address

Serial.println(WiFi.localIP());

// Route for root / web page

server.on("/", HTTP_GET, [](AsyncWebServerRequest *request){

request->send_P(200, "text/html", index_html, processor);

});

// Send a GET request to <ESP_IP>/slider?value=<inputMessage>

server.on("/slider", HTTP_GET, [] (AsyncWebServerRequest *request) {

String inputMessage;

// GET input1 value on <ESP_IP>/slider?value=<inputMessage>

if (request->hasParam(PARAM_INPUT)) {

inputMessage = request->getParam(PARAM_INPUT)->value();

sliderValue = inputMessage;

ledcWrite(ledChannel, sliderValue.toInt());

}

else {

inputMessage = "No message sent";

}

Serial.println(inputMessage);

request->send(200, "text/plain", "OK");

});

// Start server

server.begin();

//================MQTT=====================

client.setServer(mqtt_server, 1883);

client.setCallback(callback);

}

void loop() {

loop_mqtt();

}

[{"id":"b3e673b9a2a27073","type":"ui_slider","z":"9459afd070c7170a","name":"","label":"slider","tooltip":"","group":"fc89dc38.347898","order":34,"width":"16","height":"6","passthru":true,"outs":"end","topic":"topic","topicType":"msg","min":0,"max":"255","step":1,"className":"","x":290,"y":100,"wires":[["5c189735a713b0b4"]]},{"id":"5c189735a713b0b4","type":"mqtt out","z":"9459afd070c7170a","name":"","topic":"alex9ufo/esp32/slider/input","qos":"1","retain":"","respTopic":"","contentType":"","userProps":"","correl":"","expiry":"","broker":"3d43a51a.c133a2","x":540,"y":100,"wires":[]},{"id":"fc89dc38.347898","type":"ui_group","name":"LED show","tab":"ec4c23e9246d7836","order":1,"disp":true,"width":16,"collapse":false,"className":""},{"id":"3d43a51a.c133a2","type":"mqtt-broker","name":"broker.mqtt-dashboard.com","broker":"broker.mqtt-dashboard.com","port":"1883","clientid":"","usetls":false,"protocolVersion":"4","keepalive":"60","cleansession":true,"birthTopic":"","birthQos":"0","birthRetain":"false","birthPayload":"","birthMsg":{},"closeTopic":"","closePayload":"","closeMsg":{},"willTopic":"","willQos":"0","willRetain":"false","willPayload":"","willMsg":{},"sessionExpiry":""},{"id":"ec4c23e9246d7836","type":"ui_tab","name":"Home","icon":"dashboard","disabled":false,"hidden":false}]

2021年12月27日星期一

ESP32 Web Server & MQTT &Node-RED

ESP32 Web Server & MQTT &Node-RED

#include <WiFi.h>

//================MQTT=====================

#include <PubSubClient.h> //MQTT

// Replace with your network credentials

//const char* ssid = "REPLACE_WITH_YOUR_SSID";

//const char* password = "REPLACE_WITH_YOUR_PASSWORD";

const char* ssid = "TOTOLINK_A3002MU";

const char* password = "24063173";

//================MQTT=====================

const char* mqtt_server = "broker.mqtt-dashboard.com" ; //MQTT

// Set web server port number to 80

WiFiServer server(80);

// Variable to store the HTTP request

String header;

//================MQTT=====================

WiFiClient espClient;

PubSubClient client(espClient);

long lastMsg = 0;

char msg[50];

// Auxiliar variables to store the current output state

String output26State = "off";

String output27State = "off";

// Assign output variables to GPIO pins

const int output26 = 26;

const int output27 = 27;

// Current time

unsigned long currentTime = millis();

// Previous time

unsigned long previousTime = 0;

// Define timeout time in milliseconds (example: 2000ms = 2s)

const long timeoutTime = 2000;

//================MQTT=====================

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

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

Serial.print(topic);

Serial.print(". Message: ");

String messageTemp;

for (int i = 0; i < length; i++) {

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

messageTemp += (char)message[i];

}

Serial.println();

// Feel free to add more if statements to control more GPIOs with MQTT

// If a message is received on the topic esp32/output, you check if the message is either "on" or "off".

// Changes the output state according to the message

if (String(topic) == "alex96ufo/esp32/input/26") {

Serial.print("Changing output to ");

if(messageTemp == "on"){

Serial.println("on");

output26State = "on";

digitalWrite(output26, HIGH);

}

else if(messageTemp == "off"){

Serial.println("off");

output26State = "off";

digitalWrite(output26, LOW);

}

if (String(topic) == "alex96ufo/esp32/input/27") {

Serial.print("Changing output to ");

if(messageTemp == "on"){

Serial.println("on");

output27State = "on";

digitalWrite(output27, HIGH);

}

else if(messageTemp == "off"){

Serial.println("off");

output27State = "off";

digitalWrite(output27, LOW);

}

loop_mqtt();

}

//================MQTT=====================

void reconnect() {

// Loop until we're reconnected

while (!client.connected()) {

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

// Attempt to connect

if (client.connect("ESP32Client")) {

Serial.println("connected");

// Subscribe

client.subscribe("alex9ufo/esp32/input/26");

client.subscribe("alex9ufo/esp32/input/27");

} else {

Serial.print("failed, rc=");

Serial.print(client.state());

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

// Wait 5 seconds before retrying

delay(5000);

}

//================MQTT=====================

void loop_mqtt(){

if (!client.connected()) {

reconnect();

}

client.loop();

long now = millis();

if (now - lastMsg > 5000) {

lastMsg = now;

char tempString26[4];

char tempString27[4];

output26State.toCharArray(tempString26, 4);

output27State.toCharArray(tempString27, 4);

// Convert the value to a char array

client.publish("alex96ufo/esp32/output/26", tempString26);

client.publish("alex96ufo/esp32/output/27", tempString27);

}

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

void setup() {

Serial.begin(115200);

// Initialize the output variables as outputs

pinMode(output26, OUTPUT);

pinMode(output27, OUTPUT);

// Set outputs to LOW

digitalWrite(output26, LOW);

digitalWrite(output27, LOW);

// Connect to Wi-Fi network with SSID and password

Serial.print("Connecting to ");

Serial.println(ssid);

WiFi.begin(ssid, password);

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

delay(500);

Serial.print(".");

}

// Print local IP address and start web server

Serial.println("");

Serial.println("WiFi connected.");

Serial.println("IP address: ");

Serial.println(WiFi.localIP());

server.begin();

//================MQTT=====================

client.setServer(mqtt_server, 1883);

client.setCallback(callback);

}

void loop(){

loop_mqtt();

WiFiClient client = server.available(); // Listen for incoming clients

if (client) { // If a new client connects,

currentTime = millis();

previousTime = currentTime;

Serial.println("New Client."); // print a message out in the serial port

String currentLine = ""; // make a String to hold incoming data from the client

while (client.connected() && currentTime - previousTime <= timeoutTime) { // loop while the client's connected

currentTime = millis();

if (client.available()) { // if there's bytes to read from the client,

char c = client.read(); // read a byte, then

Serial.write(c); // print it out the serial monitor

header += c;

if (c == '\n') { // if the byte is a newline character

// if the current line is blank, you got two newline characters in a row.

// that's the end of the client HTTP request, so send a response:

if (currentLine.length() == 0) {

// HTTP headers always start with a response code (e.g. HTTP/1.1 200 OK)

// and a content-type so the client knows what's coming, then a blank line:

client.println("HTTP/1.1 200 OK");

client.println("Content-type:text/html");

client.println("Connection: close");

client.println();

// turns the GPIOs on and off

if (header.indexOf("GET /26/on") >= 0) {

Serial.println("GPIO 26 on");

output26State = "on";

digitalWrite(output26, HIGH);

} else if (header.indexOf("GET /26/off") >= 0) {

Serial.println("GPIO 26 off");

output26State = "off";

digitalWrite(output26, LOW);

} else if (header.indexOf("GET /27/on") >= 0) {

Serial.println("GPIO 27 on");

output27State = "on";

digitalWrite(output27, HIGH);

} else if (header.indexOf("GET /27/off") >= 0) {

Serial.println("GPIO 27 off");

output27State = "off";

digitalWrite(output27, LOW);

}

// Display the HTML web page

client.println("<!DOCTYPE html><html>");

client.println("<head><meta name=\"viewport\" content=\"width=device-width, initial-scale=1\">");

client.println("<link rel=\"icon\" href=\"data:,\">");

// CSS to style the on/off buttons

// Feel free to change the background-color and font-size attributes to fit your preferences

client.println("<style>html { font-family: Helvetica; display: inline-block; margin: 0px auto; text-align: center;}");

client.println(".button { background-color: #4CAF50; border: none; color: white; padding: 16px 40px;");

client.println("text-decoration: none; font-size: 30px; margin: 2px; cursor: pointer;}");

client.println(".button2 {background-color: #555555;}</style></head>");

// Web Page Heading

client.println("<body><h1>ESP32 Web Server</h1>");

// Display current state, and ON/OFF buttons for GPIO 26

client.println("<p>GPIO 26 - State " + output26State + "</p>");

// If the output26State is off, it displays the ON button

if (output26State=="off") {

client.println("<p><a href=\"/26/on\"><button class=\"button\">ON</button></a></p>");

} else {

client.println("<p><a href=\"/26/off\"><button class=\"button button2\">OFF</button></a></p>");

}

// Display current state, and ON/OFF buttons for GPIO 27

client.println("<p>GPIO 27 - State " + output27State + "</p>");

// If the output27State is off, it displays the ON button

if (output27State=="off") {

client.println("<p><a href=\"/27/on\"><button class=\"button\">ON</button></a></p>");

} else {

client.println("<p><a href=\"/27/off\"><button class=\"button button2\">OFF</button></a></p>");

}

client.println("</body></html>");

// The HTTP response ends with another blank line

client.println();

// Break out of the while loop

break;

} else { // if you got a newline, then clear currentLine

currentLine = "";

}

} else if (c != '\r') { // if you got anything else but a carriage return character,

currentLine += c; // add it to the end of the currentLine

}

// Clear the header variable

header = "";

// Close the connection

client.stop();

Serial.println("Client disconnected.");

Serial.println("");

}

2021年12月23日星期四

MySQL Tutorial

https://www.mysqltutorial.org/

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alex9ufo 聰明人求知心切

2021年12月31日星期五

ESP32 Web Server with Slider & MQTT : Control LED Brightness (PWM)

2021年12月27日星期一

ESP32 Web Server & MQTT &Node-RED

2021年12月23日星期四

MySQL Tutorial

Getting Started

Getting Started with MySQL

MySQL Tutorial for Developers

MySQL Basics

MySQL Stored Procedures

MySQL Triggers

MySQL Views

MySQL Index

MySQL Full-Text Search

MySQL Tips

MySQL Programming Interfaces

PHP MySQL Tutorial

MySQL Node.js

MySQL JDBC Tutorial

Python MySQL Tutorial

Perl MySQL Tutorial

MySQL Tutorial for Database Administrators

MySQL Administration

MySQL Functions

MySQL Aggregate Functions

MySQL Comparison Functions

MySQL Control Flow Functions and Expressions

MySQL Date Functions

MySQL String Functions

MySQL Window Functions

MySQL Math Functions

MySQL Tutorial References

Messaging API作為替代方案

2021年12月31日 星期五

2021年12月27日 星期一

2021年12月23日 星期四

Getting Started

MySQL Tutorial for Developers

MySQL Programming Interfaces

MySQL Tutorial for Database Administrators

MySQL Functions

MySQL Tutorial References

2021年12月31日星期五

2021年12月27日星期一

2021年12月23日星期四