data stops after 6-7 transmissions

Hi team I am Shashank Verma, I am using arduino r4 wifi to send data on thing speak. I am uploading real time data of temp, humidity, Gas conc, and AQI catagory. I am using Thingspeak free account and only sending data in every 2 min. but the transmission of data stops after 7-8 data upload. please help me in this i am builing this project in public intrest.

the public channel url is " https://thingspeak.com/channels/2606075"

Uploads starts again as soon as i restart arduino.

the arduino code i am using is as follows

"#include <DHT.h>
#include <WiFi.h>
#include <ArduinoHttpClient.h>
#include "ArduinoGraphics.h"
#include "Arduino_LED_Matrix.h"
// Define the pin and type for the DHT sensor
#define DHTPIN 2
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE); // Initialize DHT sensor
// Initialize the LED matrix
ArduinoLEDMatrix matrix;

// Replace with your network credentials
const char* ssid = "BSNL123";
const char* password = "yyyyyyyy";
const char* api_key = "xxxxxxxxxxxxxxxx";
const char* thingspeak_server = "api.thingspeak.com";
const int analogPin = A0;
const float slope = 0.1;
const float intercept = 0.5;
// Initialize the WiFi server on port 80
WiFiServer wifiServer(80);

// Timing variables for various updates
unsigned long lastMatrixUpdate = 0;
const unsigned long matrixUpdateInterval = 25000; // 25 seconds
unsigned long lastSerialUpdate = 0;
const unsigned long serialUpdateInterval = 55000; // 55 seconds

unsigned long lastThingSpeakUpdate = 0;
const unsigned long thingSpeakUpdateInterval = 60000; // 1 minute

unsigned long lastWebDataSent = 0;
const unsigned long webDataUpdateInterval = 10000; // 10 seconds to handle page refresh

// Function to determine AQI category and numeric value
void getAQICategory(float concentration, String &category, int &numericValue) {
if (concentration <= 50) {
    category = "Good";
    numericValue = 1;
    } else if (concentration <= 100) {
        category = "Satisfactory";
        numericValue = 2;
        } else if (concentration <= 200) {
            category = "Moderate";
            numericValue = 3;
            } else if (concentration <= 300) {
                category = "Poor";
                numericValue = 4;
                } else if (concentration <= 400) {
                    category = "Very Poor";
                    numericValue = 5;
                    } else {
                        category = "Severe";
                        numericValue = 6;
                        }
                    }
                    
                    void connectToWiFi() {
                    WiFi.begin(ssid, password);
                    Serial.print("Connecting to Wi-Fi");
                    int attempts = 0;
                    while (WiFi.status() != WL_CONNECTED && attempts < 20) {
                        delay(500);
                        Serial.print(".");
                        attempts++;
                        }
                        
                        if (WiFi.status() == WL_CONNECTED) {
                            Serial.println();
                            Serial.println("Connected to Wi-Fi");
                            Serial.print("IP Address: ");
                            Serial.println(WiFi.localIP());
                            } else {
                                Serial.println();
                                Serial.println("Failed to connect to Wi-Fi");
                                }
                            }
                            
                            void reconnectToThingSpeak() {
                            Serial.println("Reconnecting to ThingSpeak...");
                            delay(10000); // Wait before attempting to reconnect
                            }
                            
                            void setup() {
                            Serial.begin(115200);
                            dht.begin();
                            matrix.begin();
                            matrix.beginDraw();
                            matrix.stroke(0xFFFFFFFF);
                            const char text[] = "Temp & Humidity";
                            matrix.textFont(Font_4x6);
                            matrix.beginText(0, 1, 0xFFFFFF);
                            matrix.println(text);
                            matrix.endText();
                            matrix.endDraw();
                            delay(2000);
                            connectToWiFi();
                            
                            // Start the server
                            wifiServer.begin();
                            }
                            void loop() {
                            unsigned long currentMillis = millis();
                            
                            if (WiFi.status() != WL_CONNECTED) {
                                connectToWiFi();
                                }
                                // Read temperature and humidity from the DHT22 sensor
                                float temperature = dht.readTemperature(); // in Celsius
                                float humidity = dht.readHumidity();       // in percentage
                                // Check if the reading is valid
                                    if (isnan(temperature) || isnan(humidity)) {
                                        Serial.println("Failed to read from DHT sensor!");
                                        return;
                                        }
                                        // Convert temperature to Fahrenheit
                                        float ftemp = temperature;
                                        
                                        // Read analog value from MQ135
                                        int sensorValue = analogRead(analogPin);
                                        float gasConcentration = (slope * sensorValue) + intercept;  // Convert to gas concentration
                                        String aqiCategory;
                                        int aqiCategoryNumeric;
                                        getAQICategory(gasConcentration, aqiCategory, aqiCategoryNumeric); // Get AQI category and numeric value
                                        
                                        // Display data on the LED matrix
                                        if (currentMillis - lastMatrixUpdate >= matrixUpdateInterval) {
                                            matrix.beginDraw();
                                            matrix.clear();
                                            matrix.stroke(0xFFFFFFFF);
                                            
                                            matrix.textScrollSpeed(90);
                                            matrix.textFont(Font_5x7);
                                            matrix.beginText(0, 1, 0xFFFFFF);
                                            matrix.println("Temp: " + String(ftemp, 1) + " C");
                                            matrix.endText(SCROLL_LEFT);
                                            delay(2000);
                                            
                                            matrix.clear();
                                            matrix.beginText(0, 1, 0xFFFFFF);
                                            matrix.println("Hum: " + String(humidity, 1) + " %");
                                            matrix.endText(SCROLL_LEFT);
                                            delay(2000);
                                            
                                            matrix.clear();
                                            matrix.beginText(0, 1, 0xFFFFFF);
                                            matrix.println("AQI: " + aqiCategory);
                                            matrix.endText(SCROLL_LEFT);
                                            delay(2000);
                                            
                                            matrix.endDraw();
                                            lastMatrixUpdate = currentMillis;
                                            }
                                            
                                            // Display data on the serial monitor
                                            if (currentMillis - lastSerialUpdate >= serialUpdateInterval) {
                                                Serial.print("Temperature: ");
                                                Serial.print(ftemp);
                                                Serial.println(" C");
                                                Serial.print("Humidity: ");
                                                Serial.print(humidity);
                                                Serial.println(" %");
                                                Serial.print("MQ135 Analog Value: ");
                                                Serial.println(sensorValue);
                                                Serial.print("Gas Concentration (ppm): ");
                                                Serial.println(gasConcentration);
                                                Serial.print("AQI Category: ");
                                                Serial.println(aqiCategory);
                                                
                                                lastSerialUpdate = currentMillis;
                                                }

  // Handle Wi-Fi client connections and send data to the local LAN
  WiFiClient client = wifiServer.available();
  if (client) {
    Serial.println("Client connected");

    // Read the client's request
    String request = client.readStringUntil('\r');
    client.flush();
    // Check if it's time to update the web data
    if (currentMillis - lastWebDataSent >= webDataUpdateInterval) {
      // Send the HTTP response
      client.print("HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\n");
      client.print("<!DOCTYPE HTML><html><head><title>Air Quality Monitor</title></head><body>");
      client.print("<h1>Temperature and Humidity</h1>");
      client.print("<p>Temperature: ");
      client.print(ftemp);
      client.print(" &deg;C</p>");
      client.print("<p>Humidity: ");
      client.print(humidity);
      client.print(" %</p>");
      client.print("<p>AQI: ");
      client.print(aqiCategory);
      client.print("</p>");
      client.print("<p>Gas Concentration: ");
      client.print(gasConcentration);
      client.print(" ppm</p>");
      client.print("</body></html>");
      lastWebDataSent = currentMillis; // Update the time of the last data sent
      Serial.println("Data sent to client");
    } else {
      // Inform the client that the data has not changed
      client.print("HTTP/1.1 304 Not Modified\r\nContent-Type: text/html\r\n\r\n");
      client.print("<!DOCTYPE HTML><html><head><title>Air Quality Monitor</title></head><body>");
      client.print("<h1>Temperature and Humidity</h1>");
      client.print("<p>Data not updated. Please refresh the page to get new data.</p>");
      client.print("</body></html>");
    }
    
    delay(1000);
    client.stop();
    Serial.println("Client disconnected");
  }
  // Send data to ThingSpeak
  if (currentMillis - lastThingSpeakUpdate >= thingSpeakUpdateInterval) {
    bool success = false;
    int retryCount = 0;
    const int maxRetries = 3;
    while (retryCount < maxRetries && !success) {
      if (WiFi.status() == WL_CONNECTED) {
        WiFiClient wifiClient;
        HttpClient httpClient = HttpClient(wifiClient, thingspeak_server, 80);
        httpClient.setTimeout(20000); // Set a timeout of 20 seconds
        String url = "/update?api_key=" + String(api_key) +
                     "&field1=" + String(temperature) +
                     "&field2=" + String(humidity) +
                     "&field3=" + String(gasConcentration) +
                     "&field4=" + String(aqiCategoryNumeric); // Send AQI category as numeric
        httpClient.get(url);
        int statusCode = httpClient.responseStatusCode();
        String response = httpClient.responseBody();

        if (statusCode == 200) {
          Serial.println("Data sent to ThingSpeak");
          success = true;
        } else {
          Serial.print("Error sending data to ThingSpeak. Status code: ");
          Serial.println(statusCode);
          Serial.println("Response: ");
          Serial.println(response);
          retryCount++;
          delay(5000); // Wait before
          retrying
          }
        } else {
            reconnectToThingSpeak();
            }
        }
        if (!success) {
            Serial.println("Failed to send data after multiple attempts.");
            }
            lastThingSpeakUpdate = currentMillis;
            }
            }

[Rena Berman]

(Answers Dev) Restored edit

Answer 1

[Christopher Stapels]

I recomend using the ThingSpeak library - it takes care of much of the network connectivity for you.

Are you sure its not one of your sensors that is causing the code to stop running? You could try posting static values with no sensors to test this

Network connectivity is my guess for your issue. The wifi library has a function to write RSSI, you can also log that you your channel to see how strong the signal is. Also try moving your device closer to the access point or try connecting to a different network.

As far as I can read it, your code seems fine, and your channel does not seem to show evisence of posting too fast.

Thanks for sharing your cool project, please let us know if you figure out the issue.

[Shashank]

thanks for your response. tried testing with this random data without sensors still data transmission stops after 7-8 successfull transmissions. i fail to understand the reason. plaese help in finding the solution.

#include <WiFi.h>
#include <ArduinoHttpClient.h>

// Replace with your network credentials and ThingSpeak API key
const char* ssid = "BSNL123";
const char* password = "xxxxxxxxx";
const char* api_key = "xxxxxxxxxxxxxxx";
const char* thingspeak_server = "api.thingspeak.com";

// Timing variables for sending data
unsigned long lastThingSpeakUpdate = 0;
const unsigned long thingSpeakUpdateInterval = 60000; // 1 minute

void connectToWiFi() {
  WiFi.begin(ssid, password);
  Serial.print("Connecting to Wi-Fi");

  int attempts = 0;
  while (WiFi.status() != WL_CONNECTED && attempts < 20) {
    delay(500);
    Serial.print(".");
    attempts++;
  }

  if (WiFi.status() == WL_CONNECTED) {
    Serial.println();
    Serial.println("Connected to Wi-Fi");
    Serial.print("IP Address: ");
    Serial.println(WiFi.localIP());
  } else {
    Serial.println();
    Serial.println("Failed to connect to Wi-Fi");
  }
}

void setup() {
  Serial.begin(115200);
  connectToWiFi();
}

void loop() {
  unsigned long currentMillis = millis();

  // Send random data to ThingSpeak every minute
  if (currentMillis - lastThingSpeakUpdate >= thingSpeakUpdateInterval) {
    if (WiFi.status() == WL_CONNECTED) {
      WiFiClient wifiClient;
      HttpClient httpClient = HttpClient(wifiClient, thingspeak_server, 80);

      int randomData = random(0, 101); // Generate random number between 0 and 100

      String url = "/update?api_key=" + String(api_key) + "&field1=" + String(randomData);
      httpClient.get(url);

      int statusCode = httpClient.responseStatusCode();
      String response = httpClient.responseBody();

      if (statusCode == 200) {
        Serial.println("Data sent to ThingSpeak");
        Serial.print("Random Data: ");
        Serial.println(randomData);
      } else {
        Serial.print("Error sending data to ThingSpeak. Status code: ");
        Serial.println(statusCode);
        Serial.println("Response: ");
        Serial.println(response);
      }
    } else {
      connectToWiFi();
    }

    lastThingSpeakUpdate = currentMillis;
  }
}

[Christopher Stapels]

you have the connection attempts at 20, Im wondering if that means your network strength is too low.

I would try moving to a stronger network.

Alos, for this:

while (WiFi.status() != WL_CONNECTED && attempts < 20) {
    delay(500);
    Serial.print(".");
    attempts++;
    }
    

I have found that 500 is not long enough to connect when the network is weak, I recomend increasing this time to a few seconds.

    delay(4000); //perhaps    

[Shashank]

thanks a lot sir. problem is solved now thanks for your support and guidance.