Assistance Required

Need Help With My Project
1

Hello everyone, I’m currently working on a home automation project using LoRa. I am using Blynk which is connected to an esp8266 on the sender side.
i)Sender Circuit:

  • Microcontroller: ESP8266 (Wi-Fi module)
  • Wireless Communication: LoRa RA-02 module for long-range communication
  • Integration: Connected to a home automation app for remote operations

ii)Receiver Circuit:

  • Microcontroller: Arduino Uno
  • Sensors and Actuators:
    • DHT11 (Temperature and Humidity Sensor)
    • PIR Motion Sensor
    • 2-Channel Relay (to control a bulb and a fan)
      Wireless Communication:* LoRa RA-02 module receiving commands from the sender

However, I’ve encountered a problem with the relay control on the receiver side. It seems like the bulb and fan are not being switched on/off at all. I’ll be grateful for any pointers on where the problem could be

Sender:
#include <ESP8266WiFi.h>
#include <LoRa.h>

// WiFi network details
const char* ssid = " ";
const char* password = " ";

// Blynk authentication token
#define BLYNK_TEMPLATE_ID "TMPL2eJutAnKH"
#define BLYNK_TEMPLATE_NAME "LoRa Ra 02 with ESP8266"
#define BLYNK_AUTH_TOKEN "ZHais_e9FkAFjqzTVa-gX37mCt8dYfeU"

#include <BlynkSimpleEsp8266.h>

const int csPin = D8;
const int resetPin = D0;
const int irqPin = D2;

String temperature = "N/A";
String humidity = "N/A";
String motionState = "N/A";

void setup() {
 Serial.begin(9600);
 WiFi.begin(ssid, password);
 while (WiFi.status()!= WL_CONNECTED) {
   delay(500);
   Serial.print(".");
 }
 Serial.println("WiFi connected.");
 Serial.print("IP address: ");
 Serial.println(WiFi.localIP());
 
 // Initialize LoRa
 LoRa.setPins(csPin, resetPin, irqPin);
 if (!LoRa.begin(433E6)) {
   Serial.println("Starting LoRa failed!");
   while (1);
 }
 Serial.println("LoRa Initializing OK!");

 // Initialize Blynk
 Blynk.begin(BLYNK_AUTH_TOKEN, ssid, password);
}

void loop() {
 Blynk.run(); // Run Blynk

 int packetSize = LoRa.parsePacket();
 if (packetSize) {
   String received = "";
   while (LoRa.available()) {
     received += (char)LoRa.read();
   }
   Serial.print("Received from LoRa: "+received);
   parseLoRaMessage(received);
 }
}

void parseLoRaMessage(String received) {
 Serial.println("Received data from LoRa: " + received);

 if (received.startsWith("Temp:") && received.indexOf(",Humidity:")!= -1 && received.indexOf(",Motion:")!= -1) {
   int tempIndex = received.indexOf("Temp:") + 5;
   int humIndex = received.indexOf(",Humidity:");
   int motionIndex = received.indexOf(",Motion:");

   if (tempIndex!= -1 && humIndex!= -1 && motionIndex!= -1) {
     temperature = received.substring(tempIndex, humIndex);
     humidity = received.substring(humIndex + 10, motionIndex);
     int motionStateNum = received.substring(motionIndex + 8).toInt();
     motionState = (motionStateNum == 1)? "Yes" : "No";

     Serial.println("Temperature: " + temperature);
     Serial.println("Humidity: " + humidity);
     Serial.println("Motion State: " + motionState);
   } else {
     Serial.println("Error: Invalid format");
   }
 } else {
   Serial.println("Error: Invalid data format");
 }

 // Send sensor data to Blynk
 Blynk.virtualWrite(V0, temperature.toFloat()); // Virtual pin V0 for temperature
 Blynk.virtualWrite(V4, humidity.toFloat());    // Virtual pin V4 for humidity
 Blynk.virtualWrite(V3, motionState == "Yes"? 1 : 0); // Virtual pin V3 for motion state
}

BLYNK_WRITE(V1) {
 if (param.asInt() == 1) {
   Serial.println("Button 1 pressed");
   sendLoRaCommand("R1");
 }
}

BLYNK_WRITE(V2) {
 if (param.asInt() == 1) {
   Serial.println("Button 2 pressed");
   sendLoRaCommand("R2");
 }
}

void sendLoRaCommand(String command) {
 LoRa.beginPacket();
 LoRa.print(command);
 LoRa.endPacket();
 Serial.println("Sent LoRa command: " + command);
}

Receiver:
#include <SPI.h>
#include <LoRa.h>
#include <DHT.h>

// Define LoRa module pins
const int csPin = 10;       // LoRa radio chip select (NSS)
const int resetPin = 9;     // LoRa radio reset
const int irqPin = 2;       // Interrupt request pin (DIO0)

// Define relay pins
const int relayPinFan = 5;  // Relay for fan connected to GPIO 5
const int relayPinBulb = 6; // Relay for bulb connected to GPIO 6

// Define DHT sensor setup
#define DHTPIN 7            // DHT11 data pin
#define DHTTYPE DHT11       // DHT11 sensor type
DHT dht(DHTPIN, DHTTYPE);

// Define PIR Motion Sensor pin
const int pirPin = 8;       // PIR motion sensor pin

void setup() {
 Serial.begin(9600);
 pinMode(relayPinFan, OUTPUT);
 pinMode(relayPinBulb, OUTPUT);
 // Ensure relays are OFF by default if using Normally Open
 digitalWrite(relayPinFan, HIGH);
 digitalWrite(relayPinBulb, HIGH);

 // Initialize LoRa
 LoRa.setPins(csPin, resetPin, irqPin);
 if (!LoRa.begin(433E6)) {
   Serial.println("Starting LoRa failed!");
   while (1);
 }
 Serial.println("LoRa Receiver Ready");

 // Initialize DHT sensor
 dht.begin();

 // Initialize PIR motion sensor
 pinMode(pirPin, INPUT);
}

void loop() {
 // Read sensor data
 float humidity = dht.readHumidity();
 float temperature = dht.readTemperature();
 int motionDetected = digitalRead(pirPin);

 // Print sensor readings
 Serial.print("Temperature: ");
 Serial.print(temperature);
 Serial.print("°C, Humidity: ");
 Serial.print(humidity);
 Serial.print("%, Motion Detected: ");
 Serial.println(motionDetected ? "Yes" : "No");

 delay(1000);

 // Send sensor data via LoRa to transmitter
 sendSensorData(temperature, humidity, motionDetected);

 // Check for LoRa commands
 receiveLoRaCommand();
}

void sendSensorData(float temperature, float humidity, int motionDetected) {
 LoRa.beginPacket();
 LoRa.print("Temp:");
 LoRa.print(temperature);
 LoRa.print(",Humidity:");
 LoRa.print(humidity);
 LoRa.print(",Motion:");
 LoRa.println(motionDetected ? "1" : "0");
 LoRa.endPacket();
 Serial.println("Sent sensor data via LoRa");
}

void receiveLoRaCommand() {
 int packetSize = LoRa.parsePacket();
 if (packetSize) {
   String command = "";
   while (LoRa.available()) {
     command += (char)LoRa.read();
   }
   Serial.print("Received command via LoRa: ");
   Serial.println(command);
   relayControl(command);
 }
}

void relayControl(String command) {
 if (command == "R1") {
 // Handle command for Relay 1 (Fan)
 digitalWrite(relayPinFan, !digitalRead(relayPinFan));
 Serial.println("Received command for Relay 1 (Fan)");
} else if (command == "R2") {
 // Handle command for Relay 2 (Bulb)
 digitalWrite(relayPinBulb, !digitalRead(relayPinBulb));
 Serial.println("Received command for Relay 2 (Bulb)");
}

}
2

please edit your post, using the pencil icon at the bottom, and add triple backticks at the beginning and end of your code so that it displays correctly. Triple backticks look like this: ```

4

TBH, your code is a mess.
You’re creating a WiFi connection in your first sketch then begin Blynk.begin() so the WiFi stuff is redundant.

Your second sketch has a 1 second delay in the void loop, which is going to make the responsiveness to Blynk commands very laggy.

Instead of doing this…

You’d be far better reading the pin state first, then using the NOT (!) operator on the result, but first printing the value you’re getting so that you can properly debug the code. If you’re getting unexpected results then you can read the pin value afterwards and print that to your serial monitor too.

You have lots of serial print commands in there already though, but you’ve not given us any indication about which parts of your sketches are responding as expected, and which aren’t .
If you decide to post your serial outputs then do that as text, with triple backticks too. Bear in mind that to understand your serial output we’ll need to have some narrative to explain what we’re seeing and what actions you took (like pressing a button in Blynk) to make any sense of your data.

Pete.

6

I can’t help unless you provide more information about what your serial monitors are showing.

Pete.

10

You need to add a Serial.begin() statement.

Pete.

12

It would appear that this is the issue. You are expecting commands like “R1_ON” and “R1_OFF” and that’s not what you’re getting.

Pete.

14

I don’t know.
It’s clearly a LoRa isue, and I’d suggest that you do some experimentation, maybe with two simpler sketches, to identify a better way of handling the communication with your LoRa devices.

TBH, the use of LoRa in a home automation project is unusual. Presumably you’re doing this because of poor WiFi coverage within your home?

Pete.