Upload DHT11 sensor values using GSM 900 | Arduino | Forum

AT
AT+CPIN?
AT+CREG?
AT+CGATT?
AT+CIPSHUT
AT+CIPSTATUS
ATAT+CSTT="myApn"
AT+CIICR
AT+CIFSR
AT+CIPSPRT=0
AT+CIPSTART="TCP","api.thingspeak.com","80"
AT+CIPSEND
Temperature = 23.00
GET https://api.thingspeak.com/update?api_key=QT7O3U5O8HFEFBY8&

SEND OK
359

This is what I am seeing on the serial monitor as I added:

Serial.print("Temperature = ");
Serial.println(DHT.temperature);

But the value I am seeing on thingspeak is 325.

cstapels said

Sorry, I repeated the same mistake I pointed out in your code above!

I meant for you to print str, not temp.

Can you add Serial.println(str) and share the output?

Hello no need to apologize, I am really grateful for the help and advice.

I added the Serial.println(str) and this is what I got on the serial monitor:

CONNECT OKAT+CIPSEND

GET https://api.thingspeak.com/update?api_key=QT7O3U5O8HFEFBY8&field1=01.00

Temperature = 25.00

GET https://api.thingspeak.com/update?api_key=QT7O3U5O8HFEFBY8&

#include <SoftwareSerial.h>
#include <String.h>
#include <dht.h>
int sensorPin = 0; // set the input pin for the potentiometer
int sensorValue = 0;

dht DHT;

#define DHT11_PIN A0

SoftwareSerial gprsSerial(7,8);

 

float temp=0.0;

void setup()
{
gprsSerial.begin(9600); // the GPRS baud rate
Serial.begin(9600); // the GPRS baud rate

delay(1000);
}

void loop()
{
temp=analogRead(A0);
temp=temp*0.4887;
delay(2);

if (gprsSerial.available())
Serial.write(gprsSerial.read());

gprsSerial.println("AT");
delay(1000);

gprsSerial.println("AT+CPIN?");
delay(1000);

gprsSerial.println("AT+CREG?");
delay(1000);

gprsSerial.println("AT+CGATT?");
delay(1000);

gprsSerial.println("AT+CIPSHUT");
delay(1000);

gprsSerial.println("AT+CIPSTATUS");
delay(2000);

gprsSerial.println("AT+CIPMUX=0");
delay(2000);

ShowSerialData();

gprsSerial.println("AT+CSTT=\"myApn\"");//start task and setting the APN,
delay(1000);

ShowSerialData();

gprsSerial.println("AT+CIICR");//bring up wireless connection
delay(3000);

ShowSerialData();

gprsSerial.println("AT+CIFSR");//get local IP adress
delay(2000);

ShowSerialData();

gprsSerial.println("AT+CIPSPRT=0");
delay(3000);

ShowSerialData();

gprsSerial.println("AT+CIPSTART=\"TCP\",\"api.thingspeak.com\",\"80\"");//start up the connection
delay(6000);

ShowSerialData();

gprsSerial.println("AT+CIPSEND");//begin send data to remote server
delay(4000);
ShowSerialData();

String str="GET https://api.thingspeak.com/update?api_key=QT7O3U5O8HFEFBY8&field1=0" + String(temp);
Serial.println(str);
gprsSerial.println(str);//begin send data to remote server
delay(4000);
ShowSerialData();

gprsSerial.println((char)26);//sending
delay(5000);//waitting for reply, important! the time is base on the condition of internet
gprsSerial.println();

ShowSerialData();

gprsSerial.println("AT+CIPSHUT");//close the connection
delay(100);
ShowSerialData();
}
void ShowSerialData()
{
while(gprsSerial.available()!=0)
Serial.write(gprsSerial.read());

 

int chk = DHT.read11(DHT11_PIN);
Serial.print("Temperature = ");
Serial.println(DHT.temperature);
Serial.print("Humidity = ");
Serial.println(DHT.humidity);
delay(5000);
sensorValue = analogRead(sensorPin);
delay(1000);
Serial.print("sensor = " );
Serial.println(sensorValue);
sensorValue = analogRead(sensorPin);
delay(5000);
Serial.print("sensor = " );
Serial.println(sensorValue);
}

This is the new code I uploaded and I placed the Serial.print("Temperature = "); code lines to the end of the code.

After using this code, the serial monitor shows this:

OK
CONNECT OKTemperature = 28.00
Humidity = 74.00
sensor = 1023
sensor = 1023
AT+CIPSEND
Temperature = 28.00
Humidity = 75.00
sensor = 1023
sensor = 1023
GET https://api.thingspeak.com/update?api_key=QT7O3U5O8HFEFBY8&field1=0499.94
GET https://api.thingspeak.com/update?api_key=QT7O3U5O8HFEFBY8&Temperature = 28.00
Humidity = 74.00
sensor = 1023
sensor = 1023
SEND OK
523Temperature = 28.00
Humidity = 74.00
sensor = 1023
sensor = 1023
CLOSED
Temperature = -999.00
Humidity = -999.00

 Based on what you said you were not seeing, I am now able to see:

GET https://api.thingspeak.com/update?api_key=QT7O3U5O8HFEFBY8&field1=0499.94
GET https://api.thingspeak.com/update?api_key=QT7O3U5O8HFEFBY8&Temperature = 28.00

as shown above. The problem is that the 28 value is not uploaded to thingspeak but the value I am seeing seems to be the 499.94.

String str="GET https://api.thingspeak.com/update?api_key=QT7O3U5O8HFEFBY8&field1="+String(DHT.temperature)+"?api_key=QT7O3U5O8HFEFBY8&field2="+String(DHT.humidity) ;

With more trial and error I got the two values to upload simultaneously. thanks once again for all the advice

Ok thanks, I will give the shorter version a try.