#include <WiFi.h>
#include <PubSubClient.h>
#include <DHTesp.h>
#include <Stepper.h>
#include <ESP32Servo.h>
/* NOTE:
As Gas Sensor is not available in Wokwi platform.
Slide Potentiometer is used instead of Gas Sensor, to variably set level of gas leakage.*/
#define DHTPIN 15
#define GAS_LEVEL 34 // Slide Potentiometer
#define buzzer 13
#define LED 5
const int servoPin = 12;
Servo valve;
DHTesp dhtsensor;
Stepper stepper(1000, 19,21,22,23);
void callback(char* subscribetopic, byte* payload, unsigned int payloadLength);
#define ORG "h9eaiu"
#define DEVICE_TYPE "abcde"
#define DEVICE_ID "12345"
#define TOKEN "12345678"
String data3;
float h, t, g;
int pos=0;
boolean valve_open=true;
//-------- Customise the above values --------
char server[] = ORG ".messaging.internetofthings.ibmcloud.com";
char publishTopic[] = "iot-2/evt/Data/fmt/json";
char subscribetopic[] = "iot-2/cmd/test/fmt/String";
char authMethod[] = "use-token-auth";
char token[] = TOKEN;
char clientId[] = "d:" ORG ":" DEVICE_TYPE ":" DEVICE_ID;
//-----------------------------------------
WiFiClient wifiClient;
PubSubClient client(server, 1883, callback ,wifiClient);
void setup()
{
Serial.begin(115200);
dhtsensor.setup(DHTPIN,DHTesp::DHT22);
stepper.setSpeed(100);
valve.attach(servoPin);
pinMode(GAS_LEVEL, INPUT);
pinMode(buzzer,OUTPUT);
delay(10);
Serial.println();
wificonnect();
mqttconnect();
valve.write(90);
}
void loop()
{
try
{
int duration = random(100, 1000); // Generate a random duration between 100 and 1000 milliseconds
int frequency = random(100, 10000); // Generate a random frequency between 100 and 10000 Hz
TempAndHumidity data=dhtsensor.getTempAndHumidity();
t=data.temperature;
h=data.humidity;
g=map(int(analogRead(GAS_LEVEL)), 0, 4095, 200, 2000);
Serial.print("temperature:");
Serial.println(t);
Serial.print("Humidity:");
Serial.println(h);
Serial.print("Gas Level:");
Serial.println(g);
if(g>500 || t>49)
{
tone(buzzer, 1000);
stepper.step(1000);
valve.write(180);
}
else
{
valve.write(90);
noTone(buzzer);
}
PublishData(t, h, g);
delay(1000);
if (!client.loop())
{
mqttconnect();
}
}
catch(const std::exception& e)
{
Serial.println("Exception occurred:");
Serial.println(e.what());
//handling the exception here
}
}
/*.....................................retrieving to Cloud...............................*/
void PublishData(float temp, float humid, float gas_level)
{
mqttconnect();
String payload = "{\"temperature\":";
payload += temp;
payload += "," "\"humidity\":";
payload += humid;
payload += "," "\"gas_level\":";
payload += gas_level;
payload += "}";
Serial.print("Sending payload: ");
Serial.println(payload);
if (client.publish(publishTopic, (char*) payload.c_str()))
{
Serial.println("Publish ok");
} else
{
Serial.println("Publish failed");
}
}
void mqttconnect()
{
if (!client.connected())
{
Serial.print("Reconnecting client to ");
Serial.println(server);
while (!!!client.connect(clientId, authMethod, token))
{
Serial.print(".");
delay(500);
}
initManagedDevice();
Serial.println();
}
}
void wificonnect()
{
Serial.println();
Serial.print("Connecting to ");
WiFi.begin("Wokwi-GUEST", "", 6);
while (WiFi.status() != WL_CONNECTED)
{
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
}
void initManagedDevice()
{
if (client.subscribe(subscribetopic))
{
Serial.println((subscribetopic));
Serial.println("subscribe to cmd OK");
} else {
Serial.println("subscribe to cmd FAILED");
}
}
void callback(char* subscribetopic, byte* payload, unsigned int payloadLength)
{
Serial.print("callback invoked for topic: ");
Serial.println(subscribetopic);
for (int i = 0; i < payloadLength; i++)
{
data3 += (char)payload[i];
}
Serial.println("data: "+ data3);
data3="";
}