MQTT demo code
// includes gauge feedback to input button
// Load Basic OTA first to enable wireless uploads
// Following is Adafruit MQTT example modified for wireless upload
//Corrected error in example code for button. As shown below should be Adafruit_MQTT_Subscribe onoffbutton = Adafruit_MQTT_Subscribe(&mqtt, AIO_USERNAME "/feeds/onoffbutton"); Error in code had only /feeds/onoff" which doesn't work.
/********************************************************
Adafruit MQTT Library ESP8266 Example
Must use ESP8266 Arduino from:
https://github.com/esp8266/Arduino
Works great with Adafruit's Huzzah ESP board & Feather
----> https://www.adafruit.com/product/2471
----> https://www.adafruit.com/products/2821
Adafruit invests time and resources providing this open source code,
please support Adafruit and open-source hardware by purchasing
products from Adafruit!
Written by Tony DiCola for Adafruit Industries.
MIT license, all text above must be included in any redistribution
****************************************************/
#include <ArduinoOTA.h> // Enable OTA programming 1 of 3 lines
WiFiServer server(80);
#include <ESP8266WiFi.h>
#include "Adafruit_MQTT.h"
#include "Adafruit_MQTT_Client.h"
/************************* WiFi Access Point *********************************/
#define WLAN_SSID "your SSID"
#define WLAN_PASS "your router password"
/************************* Adafruit.io Setup *********************************/
#define AIO_SERVER "io.adafruit.com"
#define AIO_SERVERPORT 1883 // use 8883 for SSL
#define AIO_USERNAME "***your username from Adafruit.io***"
#define AIO_KEY "***your Active Key from Adafruit.io***"
/************ Global State (you don't need to change this!) ******************/
// Create an ESP8266 WiFiClient class to connect to the MQTT server.
WiFiClient client;
// or... use WiFiFlientSecure for SSL
//WiFiClientSecure client;
// Setup the MQTT client class by passing in the WiFi client and MQTT server and login details.
Adafruit_MQTT_Client mqtt(&client, AIO_SERVER, AIO_SERVERPORT, AIO_USERNAME, AIO_KEY);
/****************************** Feeds ***************************************/
// Setup a feed called 'photocell' for publishing.
// Notice MQTT paths for AIO follow the form: <username>/feeds/<feedname>
Adafruit_MQTT_Publish photocell = Adafruit_MQTT_Publish(&mqtt, AIO_USERNAME "/feeds/photocell");
// Setup a feed called 'onoff' for subscribing to changes.
Adafruit_MQTT_Subscribe onoffbutton = Adafruit_MQTT_Subscribe(&mqtt, AIO_USERNAME "/feeds/onoffbutton");
/*************************** Sketch Code ************************************/
// Bug workaround for Arduino 1.6.6, it seems to need a function declaration
// for some reason (only affects ESP8266, likely an arduino-builder bug).
void MQTT_connect();
void setup() {
ArduinoOTA.begin(); // Enable OTA programming 2 of 3 lines
server.begin();
String Strreceive;
pinMode(D4, OUTPUT); // Initialize the LED_BUILTIN pin as an output
WiFi.begin(WLAN_SSID, WLAN_PASS);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
}
// Setup MQTT subscription for onoff feed.
mqtt.subscribe(&onoffbutton);
}
uint32_t x=0;
uint32_t oldx=0;
void loop() {
delay(500); //Reduce rate of messages. Use RTC later instead
ArduinoOTA.handle(); // Enable OTA programming 3 of 3 lines
// Ensure the connection to the MQTT server is alive (this will make the first
// connection and automatically reconnect when disconnected). See the MQTT_connect
// function definition further below.
MQTT_connect();
// this is our 'wait for incoming subscription packets' busy subloop
// try to spend your time here
Adafruit_MQTT_Subscribe *subscription;
while ((subscription = mqtt.readSubscription(100))) {
if (subscription == &onoffbutton) {
String(Strreceive) = (char *)onoffbutton.lastread;
}
}
String(StrON) = "ON";
String(StrOFF) = "OFF";
String(Strreceive) = (char *)onoffbutton.lastread;
if (Strreceive == StrON) digitalWrite(D4, LOW);// Turn the LED on (Note that LOW turns LED ON
if (Strreceive == StrOFF) digitalWrite(D4, HIGH);// Turn the LED off (Note that HIGH turns LED OFF
if (Strreceive == StrON) x=50;
if (Strreceive == StrOFF) x=0;
// Now we can publish stuff!
if (x != oldx){ // only publish on change
oldx = x;
photocell.publish(x); // Publish command
}
// ping the server to keep the mqtt connection alive
// NOT required if you are publishing once every KEEPALIVE seconds
/*
if(! mqtt.ping()) {
mqtt.disconnect();
}
*/
}
// Function to connect and reconnect as necessary to the MQTT server.
// Should be called in the loop function and it will take care if connecting.
void MQTT_connect() {
int8_t ret;
// Stop if already connected.
if (mqtt.connected()) {
return;
}
uint8_t retries = 3;
while ((ret = mqtt.connect()) != 0) { // connect will return 0 for connected
mqtt.disconnect();
delay(5000); // wait 5 seconds
retries--;
if (retries == 0) {
// basically die and wait for WDT to reset me
while (1);
}
}
}