#include <WiFi.h>
#include <WiFiClient.h>
#include <PubSubClient.h>
#define ADC_IN A5
#define ADC_REF 3.3
const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* hostname = "broker.hivemq.com";
int GLED=18;
long previousMillisR= 0;
int intervalR= 500;
WiFiClient espClient;
PubSubClient client(espClient);
const char* espClientName = "esp32Client_Yaoyao198993";
int PORTNUM = 1883;
void setup_wifi()
{
WiFi.begin(ssid, password);
while(WiFi.status() != WL_CONNECTED )
{
delay(1000);
Serial.print(".");
}
Serial.println();
Serial.print("Connected to ");
Serial.println(ssid);
Serial.print("Given IP by the router to ESP32 is ");
Serial.println(WiFi.localIP());
}
void connectMQTT()
{
while(!client.connected() )
{
Serial.println("Connecting to MQTT ...");
if (client.connect(espClientName) ) //, mqttUser, mqttPassword) )
{
Serial.println("Connected");
MQTTSubscribe();
}
else
{
Serial.print("Failed with state ");
Serial.print(client.state() );
delay(2000);
}
}
}
void callback(String topic, byte* payload, unsigned int length)
{
String messageTemp;
Serial.print("Message received in topic: ");
Serial.print(topic);
Serial.print(" length is: ");
Serial.println(length);
Serial.print("Data received from broker: ");
for (int i = 0; i<length; i++)
{
Serial.print( (char)payload[i] );
messageTemp += (char)payload[i];
}
/// Handle your topics and payload here
// Example
if (topic == "Yaoyao/room/LED")
{
Serial.print("Changing room LED to ");
if (messageTemp == "Off")
{
digitalWrite(GLED, HIGH);
Serial.print("Off");
}
else if (messageTemp == "On")
{
digitalWrite(GLED, LOW);
Serial.print("On");
}
}
if (topic == "Yaoyao/room/analog")
{
Serial.println();
Serial.println("messageTemp");
}
}
void MQTTSubscribe()
{
// Subsccribe to your topics here
client.subscribe("Yaoyao/room/LED");
client.subscribe("Yaoyao/room/analog");
}
void setup_MQTT()
{
client.setServer(hostname, PORTNUM);
client.setCallback(callback);
}
void setup()
{
Serial.begin(9600);
delay(5000);
pinMode(GLED, OUTPUT);
digitalWrite(GLED, LOW);
setup_wifi();
setup_MQTT();
}
void loop()
{
if ( !client.connected() )
{
connectMQTT();
}
client.loop();
long currentMillisR = millis();
if ( currentMillisR- previousMillisR>= intervalR)
{
previousMillisR = currentMillisR;
int adcRes = analogRead( ADC_IN );
delay (10);
Serial.println(adcRes);
float voltage = (float) adcRes * ADC_REF/4095;
Serial.println( voltage );
char snum[5];
itoa (adcRes, snum, 10);
client.publish("Yaoyao/room/analog",snum);
}
}