after uploading thingsspeak code to arduino the data is not showing dynamically after providing power source and i need to connect arduino to run code again in serail monitor

I have written a thingspeak arduino code for mkr1000 and uploaded it but i had problem in sending data to thingspeak once i run the code in serial monitor the values appeared in thingsspeak website , and now i unpluged the arduino board from my pc and connected it to a battery and the values are not displaying in thingspeak website and i waited for morethan 2 minutes .Then i again connected the board to my pc and opened the serial monitor in arduino ide now i can see the data appearing in thingspeak website . Do i need to run serial monitor everytime when i want to send my sensor data to arduino. or can i upload the code and use a battery directly as power souce to send data to thingspeak.

/*

WriteSingleField

Description: Writes a value to a channel on ThingSpeak every 20 seconds.

Hardware: Arduino MKR1000

!!! IMPORTANT - Modify the secrets.h file for this project with your network connection and ThingSpeak channel details. !!!

Note:

- Requires WiFi101 library version 0.15.3 or newer.

- This example is written for a network using WPA encryption. For WEP or WPA, change the WiFi.begin() call accordingly.

ThingSpeak ( https://www.thingspeak.com ) is an analytic IoT platform service that allows you to aggregate, visualize, and

analyze live data streams in the cloud. Visit https://www.thingspeak.com to sign up for a free account and create a channel.

Documentation for the ThingSpeak Communication Library for Arduino is in the README.md folder where the library was installed.

See https://www.mathworks.com/help/thingspeak/index.html for the full ThingSpeak documentation.

For licensing information, see the accompanying license file.

Copyright 2020, The MathWorks, Inc.

*/

#include <WiFi101.h>

#include "secrets.h"

#include "ThingSpeak.h" // always include thingspeak header file after other header files and custom macros

char ssid[] = SECRET_SSID; // your network SSID (name)

char pass[] = SECRET_PASS; // your network password

int keyIndex = 0; // your network key Index number (needed only for WEP)

WiFiClient client;

unsigned long myChannelNumber = SECRET_CH_ID;

const char * myWriteAPIKey = SECRET_WRITE_APIKEY;

int number = 0;

#define sensorPin A1

void setup() {

Serial.begin(9600); // Initialize serial

while (!Serial) {

; // wait for serial port to connect. Needed for Leonardo native USB port only

}

ThingSpeak.begin(client); // Initialize ThingSpeak

}

void loop() {

// Connect or reconnect to WiFi

if(WiFi.status() != WL_CONNECTED){

Serial.print("Attempting to connect to SSID: ");

Serial.println(SECRET_SSID);

while(WiFi.status() != WL_CONNECTED){

WiFi.begin(ssid, pass); // Connect to WPA/WPA2 network. Change this line if using open or WEP network

Serial.print(".");

delay(1000);

}

Serial.println("\nConnected.");

}

int reading = analogRead(sensorPin);

// Convert the reading into voltage:

float voltage = reading * (5000 / 1024.0);

// Convert the voltage into the temperature in degree Celsius:

float temp = voltage / 100;

// Print the temperature in the Serial Monitor:

//Serial.print(temp);

//Serial.print(" \xC2\xB0"); // shows degree symbol

//Serial.println("C");

// Write to ThingSpeak. There are up to 8 fields in a channel, allowing you to store up to 8 different

// pieces of information in a channel. Here, we write to field 1.

int x = ThingSpeak.writeField(myChannelNumber, 1, temp, myWriteAPIKey);

if(x == 200){

Serial.println("Channel update successful.");

}

else{

Serial.println("Problem updating channel. HTTP error code " + String(x));

}

// change the value

number++;

if(number > 99){

number = 0;

}

delay(20000); // Wait 20 seconds to update the channel again

}

Answer 1

[Chetan]

Hello @NAGUBATHULA SATYA SRIRAM,

I understand you're trying to send data to ThingSpeak when the device is powered by a battery, but you're encountering some issues.

The MKR1000 should indeed be capable of transmitting data to ThingSpeak independently of a PC connection. The challenge you're facing seems to stem from the fact that the code is programmed to wait for a serial connection in the `setup()` function, which naturally only occurs when the device is connected to a PC.

To resolve this, please consider the following steps:

1. Adjust the Serial Initialization:

- You should either comment out or entirely remove the line containing `while (!Serial)` in your `setup()` function. This change will allow your MKR1000 to continue with the Wi-Fi connection process and ultimately send data to ThingSpeak without waiting for a serial connection.

2. Verify the Power Supply:

- Make sure that the battery is providing sufficient power for the MKR1000, with particular attention to the Wi-Fi module's requirements.

3. Enhance Wi-Fi Connection Logic:

- It's crucial to ensure that the Wi-Fi module initializes correctly upon startup. Consider placing a `WiFi.begin()` call before the `while(WiFi.status() != WL_CONNECTED)` loop in your `setup()` function to establish the Wi-Fi connection right away.

Here's a revised version of the `setup()` function:

void setup() {
%Initialize serial communication at 9600 baud (optional for debugging)
Serial.begin(9600);
%Comment out or remove the following line to prevent waiting for serial connection
%while (!Serial) {
%  Wait indefinitely for Serial to connect (only necessary for debugging)
 %  }
    
 %   Start the Wi-Fi connection process
   WiFi.begin(ssid, pass);
    
   %  Wait for Wi-Fi connection to establish
        while (WiFi.status() != WL_CONNECTED) {
            delay(1000); % Wait 1 second before retrying
    %  Optionally, add an LED blink or serial print here for status indication
      }
           
     %  Initialize ThingSpeak after Wi-Fi connection is established
     ThingSpeak.begin(client);
}

4. Use Conditional Debugging:

- If you still need serial debugging, you can wrap the debugging statements in an `if (Serial)` check, which will ensure they're only executed when a serial connection is available.

By implementing these modifications, the MKR1000 should be ready to send data to ThingSpeak when powered by a battery.

I hope this helps.