Hoy van a aprender cómo usar el protocolo MQTT en la
plataforma IOT (internet de las cosas) de Adafruit (io.adafruit.com). Vamos a ver como monitorear
entradas analógicas y digitales; y como controlar salidas analógicas y
digitales.
Código Fuente:
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include "Adafruit_MQTT.h"
#include "Adafruit_MQTT_Client.h"
/************************* Adafruit.io Setup *********************************/
#define AIO_SERVER "52.70.203.194" // io.adafruit.com
#define AIO_SERVERPORT 1883 // use 8883 for SSL
#define AIO_USERNAME "alealomar"
#define AIO_KEY "8902faa03d8b4dcdbfd2b66b3a725f26"
/************ Global State (you don't need to change this!) ******************/
// Create an ESP8266 WiFiClient class to connect to the MQTT server.
WiFiClient 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_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 temperatura = Adafruit_MQTT_Publish(&mqtt, AIO_USERNAME "/feeds/temperatura");
Adafruit_MQTT_Publish pulsador = Adafruit_MQTT_Publish(&mqtt, AIO_USERNAME "/feeds/pulsador");
// Setup a feed called 'onoff' for subscribing to changes to the button
Adafruit_MQTT_Subscribe salidaDigital = Adafruit_MQTT_Subscribe(&mqtt, AIO_USERNAME "/feeds/salidaDigital", MQTT_QOS_1);
Adafruit_MQTT_Subscribe salidaAnalogica = Adafruit_MQTT_Subscribe(&mqtt, AIO_USERNAME "/feeds/salidaAnalogica", MQTT_QOS_1);
/*************************** Sketch Code ************************************/
void digitalCallback(char *data, uint16_t len) {
Serial.print("Hey we're in a onoff callback, the button value is: ");
Serial.println(data);
String message = String(data);
message.trim();
if (message == "ON") {digitalWrite(12, HIGH);}
if (message == "OFF") {digitalWrite(12, LOW);}
}
void analogicaCallback(char *data, uint16_t len) {
Serial.print("Hey we're in a onoff callback, the button value is: ");
Serial.println(data);
String message = String(data);
message.trim();
analogWrite(13, message.toInt());
}
//-------------------VARIABLES GLOBALES--------------------------
int contconexion = 0;
const char *ssid = "----";
const char *password = "----";
unsigned long previousMillis = 0;
char charPulsador [15];
String strPulsador;
String strPulsadorUltimo;
//-------------------------------------------------------------------------
void setup() {
//prepara GPI13 y 12 como salidas
pinMode(13, OUTPUT); // D7 salida analógica
analogWrite(13, 0); // analogWrite(pin, value);
pinMode(12, OUTPUT); // D6 salida digital
digitalWrite(12, LOW);
// Entradas
pinMode(14, INPUT); // D5
// Inicia Serial
Serial.begin(115200);
Serial.println("");
// Conexión WIFI
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED and contconexion <50) { //Cuenta hasta 50 si no se puede conectar lo cancela
++contconexion;
delay(500);
Serial.print(".");
}
if (contconexion <50) {
//para usar con ip fija
IPAddress ip(192,168,1,156);
IPAddress gateway(192,168,1,1);
IPAddress subnet(255,255,255,0);
WiFi.config(ip, gateway, subnet);
Serial.println("");
Serial.println("WiFi conectado");
Serial.println(WiFi.localIP());
}
else {
Serial.println("");
Serial.println("Error de conexion");
}
salidaDigital.setCallback(digitalCallback);
salidaAnalogica.setCallback(analogicaCallback);
mqtt.subscribe(&salidaDigital);
mqtt.subscribe(&salidaAnalogica);
}
//--------------------------LOOP--------------------------------
void loop() {
MQTT_connect();
unsigned long currentMillis = millis();
if (currentMillis - previousMillis >= 2000) { //envia la temperatura cada 2 segundos
previousMillis = currentMillis;
int analog = analogRead(17);
float temp = analog*0.322265625;
Serial.print(F("\nSending temperatura val "));
Serial.print(temp);
Serial.print("...");
if (! temperatura.publish(temp)) {
Serial.println(F("Failed"));
} else {
Serial.println(F("OK!"));
}
}
if (digitalRead(14) == 0) {
strPulsador = "presionado";
} else {
strPulsador = "NO presionado";
}
if (strPulsador != strPulsadorUltimo) { //envia el estado del pulsador solamente cuando cambia.
strPulsadorUltimo = strPulsador;
strPulsador.toCharArray(charPulsador, 15);
Serial.print(F("\nSending pulsador val "));
Serial.print(strPulsador);
Serial.print("...");
if (! pulsador.publish(charPulsador)) {
Serial.println(F("Failed"));
} else {
Serial.println(F("OK!"));
}
delay(1000);
}
// this is our 'wait for incoming subscription packets and callback em' busy subloop
// try to spend your time here:
mqtt.processPackets(500);
// 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;
}
Serial.print("Connecting to MQTT... ");
uint8_t retries = 3;
while ((ret = mqtt.connect()) != 0) { // connect will return 0 for connected
Serial.println(mqtt.connectErrorString(ret));
Serial.println("Retrying MQTT connection in 10 seconds...");
mqtt.disconnect();
delay(10000); // wait 10 seconds
retries--;
if (retries == 0) {
// basically die and wait for WDT to reset me
while (1);
}
}
Serial.println("MQTT Connected!");
}
