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/*
* ESP8266 (Adafruit HUZZAH) Mosquitto MQTT Publish Example
* Thomas Varnish (https://github.com/tvarnish), (https://www.instructables.com/member/Tango172)
* Made as part of my MQTT Instructable - "How to use MQTT with the Raspberry Pi and ESP8266"
*/
#include <Bounce2.h> // Used for "debouncing" the pushbutton
#include <ESP8266WiFi.h> // Enables the ESP8266 to connect to the local network (via WiFi)
#include <PubSubClient.h> // Allows us to connect to, and publish to the MQTT broker
const int ledPin = 0; // This code uses the built-in led for visual feedback that the button has been pressed
const int buttonPin = 13; // Connect your button to pin #13
// WiFi
// Make sure to update this for your own WiFi network!
const char* ssid = "TP-LINK_7224";
const char* wifi_password = "RFID7890";
// MQTT
// Make sure to update this for your own MQTT Broker!
const char* mqtt_server = "192.168.58.117";
const char* mqtt_topic = "Flash_Message";
const char* mqtt_topic_sub = "flash";
const char* mqtt_username = "pi";
const char* mqtt_password = "pi123";
// The client id identifies the ESP8266 device. Think of it a bit like a hostname (Or just a name, like Greg).
const char* clientID = "ESP01";
// Initialise the Pushbutton Bouncer object
Bounce bouncer = Bounce();
// Initialise the WiFi and MQTT Client objects
WiFiClient wifiClient;
PubSubClient client(mqtt_server, 1883, wifiClient); // 1883 is the listener port for the Broker
void ReceivedMessage(char* topic, byte* payload, unsigned int length) {
// Output the first character of the message to serial (debug)
Serial.println((char)payload[0]);
// Handle the message we received
// Here, we are only looking at the first character of the received message (payload[0])
// If it is 0, turn the led off.
// If it is 1, turn the led on.
if ((char)payload[0] == 'E' && (char)payload[1] == 'S' && (char)payload[2] == 'P' && (char)payload[3] == '0' && (char)payload[4] == '1' ) {
digitalWrite(ledPin, HIGH);
delay(4000);// Notice for the HUZZAH Pin 0, HIGH is OFF and LOW is ON. Normally it is the other way around.
digitalWrite(ledPin, LOW);
}
if ((char)payload[0] == '0') {
digitalWrite(ledPin, LOW);
delay(1000);
}
}
void setup() {
pinMode(ledPin, OUTPUT);
pinMode(buttonPin, INPUT);
// Switch the on-board LED off to start with
digitalWrite(ledPin, HIGH);
// Setup pushbutton Bouncer object
bouncer.attach(buttonPin);
bouncer.interval(5);
// Begin Serial on 115200
// Remember to choose the correct Baudrate on the Serial monitor!
// This is just for debugging purposes
Serial.begin(115200);
Serial.print("Connecting to ");
Serial.println(ssid);
// Connect to the WiFi
WiFi.begin(ssid, wifi_password);
// Wait until the connection has been confirmed before continuing
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
// Debugging - Output the IP Address of the ESP8266
Serial.println("WiFi connected");
Serial.print("IP address: ");
Serial.println(WiFi.localIP());
client.setCallback(ReceivedMessage);
// Connect to MQTT Broker
// client.connect returns a boolean value to let us know if the connection was successful.
// If the connection is failing, make sure you are using the correct MQTT Username and Password (Setup Earlier in the Instructable)
if (client.connect(clientID, mqtt_username, mqtt_password)) {
client.subscribe(mqtt_topic_sub);
Serial.println("Connected to MQTT Broker!");
}
else {
Serial.println("Connection to MQTT Broker failed...");
}
}
bool Connect() {
// Connect to MQTT Server and subscribe to the topic
if (client.connect(clientID, mqtt_username, mqtt_password)) {
client.subscribe(mqtt_topic_sub);
return true;
}
else {
return false;
}
}
void loop() {
// Update button state
// This needs to be called so that the Bouncer object can check if the button has been pressed
bouncer.update();
if (bouncer.rose()) {
// Turn light on when button is pressed down
// (i.e. if the state of the button rose from 0 to 1 (not pressed to pressed))
digitalWrite(ledPin, LOW);
if (!client.connected()) {
Connect();
}
// PUBLISH to the MQTT Broker (topic = mqtt_topic, defined at the beginning)
// Here, "Button pressed!" is the Payload, but this could be changed to a sensor reading, for example.
if (client.publish(mqtt_topic, "Button pressed!")) {
Serial.println("Button pushed and message sent!");
}
// Again, client.publish will return a boolean value depending on whether it succeded or not.
// If the message failed to send, we will try again, as the connection may have broken.
else {
Serial.println("Message failed to send. Reconnecting to MQTT Broker and trying again");
client.connect(clientID, mqtt_username, mqtt_password);
delay(10); // This delay ensures that client.publish doesn't clash with the client.connect call
client.publish(mqtt_topic, "Button pressed!");
}
}
else if (bouncer.fell()) {
// Turn light off when button is released
// i.e. if state goes from high (1) to low (0) (pressed to not pressed)
digitalWrite(ledPin, HIGH);
}
client.loop();
}