Last active
April 2, 2019 11:09
-
-
Save li2hub/f4b24b6635dc432689e60dd044e73494 to your computer and use it in GitHub Desktop.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
#include <ESP8266WiFi.h> | |
#include <PubSubClient.h> | |
const char* ssid = "YOUR_SSID"; | |
const char* password = "YOUR_PASSWORD"; | |
const char* mqtt_server = "192.168.XX.XXX";// Your Raspberry Pi IP address | |
WiFiClient espClient; | |
PubSubClient client(espClient); | |
long lastMsg = 0; | |
char msg[50]; | |
int value = 0; | |
void setup() { | |
pinMode(LED_BUILTIN, 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("ESP8266Client")) { | |
Serial.println("connected"); | |
// ... and resubscribe | |
client.subscribe("led_topic"); | |
} 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=analogRead(A0); | |
snprintf (msg, 75, "%ld", value); | |
Serial.print("Publish message: "); | |
Serial.println(msg); | |
client.publish("sensor_data", msg); | |
} | |
} |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment