subscribe to mutible mqtt topics
Posted: Sat Dec 31, 2016 7:17 amHello
I like to create a neopixel (24 ledring) gauge with an esp8266 with mqtt.
Like to use pubsubclient to subscribe to 4 topics
1) color1 (string) hex color (first color)
2) color2 (string) hex color (second color
3) gauge (int) value
4 mode (string) gauge mode (different mode types like fading color, etc...
But i have no idea how to get pubsubclient subscribe to 4 mqtt topics.
Can anyone set me in a good direction
Like to use this script
I like to create a neopixel (24 ledring) gauge with an esp8266 with mqtt.
Like to use pubsubclient to subscribe to 4 topics
1) color1 (string) hex color (first color)
2) color2 (string) hex color (second color
3) gauge (int) value
4 mode (string) gauge mode (different mode types like fading color, etc...
But i have no idea how to get pubsubclient subscribe to 4 mqtt topics.
Can anyone set me in a good direction
Like to use this script
Code: Select all
#include <ESP8266WiFi.h>
#include <PubSubClient.h>
// Update these with values suitable for your network.
const char* ssid = "........";
const char* password = "........";
const char* mqtt_server = "broker.mqtt-dashboard.com";
WiFiClient espClient;
PubSubClient client(espClient);
long lastMsg = 0;
char msg[50];
int value = 0;
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("ESP8266Client")) {
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 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 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);
}
}