Changes
MQTT
,Ajout second exemple PubSubClient
Notre sonoff va s'instancier sur le réseau en contactant le broker dont nous lui avons donné l'adresse IP en souscrivant au service (topic) /sonoff. Quand un objet publiera une donnée 1 sur le topic /sonoff la lampe s'allumera et s'étendra à la réception d'un 0
=== Publier ===
Sur un smartphone Android -par exemple - on peut pourra charger l'application '''MQTT Dash''', se raccorder au Broker mis en place par François et créer un service de bouton on/off qui publiera sur le topic /sonoff et enverra des ordres d'allumage (1) ou d'extinction (0).Cette application permet de publier et de souscrire à tout type de services.
== Un exemple d'utilisation avec un SonOff en commande d'éclairage ==
Les Sonoff sont de petits interrupteurs construits autour d'un ESP8266 et d'un relais 10A.
Les PIN exposées du dispositif permettent de le reflasher pour commander le relais en souscrivant à un service n/off. (une pin-GPIO14) reste disponible pour y connecter un capteur et donc publier cette information.
=== Raccordement pour flashage ===
Pour le raccorder, il faut un petit dispositif UART<->USB celui du FabLab (permet de travailler en 3.3v ce qui est pratique pour cet usage.
Pour le flasher il faut appuyer sur le long bouton reset avant la mise sous tension (par l'USB).
[[File:Sonoff.png | 400 px]]
=== Le code en service ===
J'ai utilisé la librairie d'Adafruit que j'ai testée aussi en SSL/TLS, mais je vais essayer PubSubClient de Nick O'Leary qui a bonne réputation.
<nowiki>
/***************************************************
}
Serial.println("MQTT Connected!");
}
</nowiki>
=== Le code avec PubSubClient ===
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/*
Basic ESP8266 MQTT example
This sketch demonstrates the capabilities of the pubsub library in combination
with the ESP8266 board/library.
It connects to an MQTT server then:
- publishes "hello world" to the topic "outTopic" every two seconds
- subscribes to the topic "inTopic", printing out any messages
it receives. NB - it assumes the received payloads are strings not binary
- If the first character of the topic "inTopic" is an 1, switch ON the ESP Led,
else switch it off
It will reconnect to the server if the connection is lost using a blocking
reconnect function. See the 'mqtt_reconnect_nonblocking' example for how to
achieve the same result without blocking the main loop.
To install the ESP8266 board, (using Arduino 1.6.4+):
- Add the following 3rd party board manager under "File -> Preferences -> Additional Boards Manager URLs":
http://arduino.esp8266.com/stable/package_esp8266com_index.json
- Open the "Tools -> Board -> Board Manager" and click install for the ESP8266"
- Select your ESP8266 in "Tools -> Board"
*/
#include <WiFi.h>
#include <PubSubClient.h>
// Update these with values suitable for your network.
const char* ssid = "FIXME-NAT";
const char* password = "XXXXXXXXXXX";
const char* mqtt_server = "62.220.135.221";
const char* broker_user = "fixme"
const char* broker_passwd = "YYYYYYYYYYY"
const char* client_key_uniq = "Achanger1234" // Doit différer d'un client à l'autre
WiFiClient espClient;
PubSubClient client(espClient);
long lastMsg = 0;
char msg[50];
int value = 0;
void setup() {
pinMode(BUILTIN_LED, OUTPUT); // Initialize the BUILTIN_LED pin as an output
Serial.begin(115200);
setup_wifi();
client.setServer(mqtt_server, 1883);
client.setCallback(callback);
}
void setup_wifi() {
delay(10);
// We start by connecting to a WiFi network
Serial.println();
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
}
void callback(char* topic, byte* payload, unsigned int length) {
Serial.print("Message arrived [");
Serial.print(topic);
Serial.print("] ");
for (int i = 0; i < length; i++) {
Serial.print((char)payload[i]);
}
Serial.println();
// Switch on the LED if an 1 was received as first character
if ((char)payload[0] == '1') {
digitalWrite(BUILTIN_LED, LOW); // Turn the LED on (Note that LOW is the voltage level
// but actually the LED is on; this is because
// it is acive low on the ESP-01)
} else {
digitalWrite(BUILTIN_LED, HIGH); // Turn the LED off by making the voltage HIGH
}
}
void reconnect() {
// Loop until we're reconnected
while (!client.connected()) {
Serial.print("Attempting MQTT connection...");
// Attempt to connect
if (client.connect(client_key_uniq,broker_user,broker_passwd)) {
Serial.println("connected");
// Once connected, publish an announcement...
//client.publish("outTopic", "hello world");
// ... and resubscribe
client.subscribe("inTopic");
} else {
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" try again in 5 seconds");
// Wait 5 seconds before retrying
delay(5000);
}
}
}
void loop() {
if (!client.connected()) {
reconnect();
}
client.loop();
/*
long now = millis();
if (now - lastMsg > 2000) {
lastMsg = now;
++value;
snprintf (msg, 75, "hello world #%ld", value);
Serial.print("Publish message: ");
Serial.println(msg);
// client.publish("outTopic", msg);
*/
}
}
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