Arduino_GSM900 Missed call based get Temperature & Humidity via SMS

With this project you get the value of temperature and humidity via a missed call.

when you try to make call to the inserted SIM no. in SIM900 module, the call is autamatically dissconeected and you will receive the SMS of cureent value of temperature and humidity.

I am using DHT11 module.

for more accurate data should use DHT22 module.

monitor the status of module on serial monitor.

For more details and inquiry: rishikeshucer@gmail.com

Requirement :

• Arduino UNO
• GSM900 Module
• 12 V/1A power supply for GSM module & 9 to 12 / 500 mA power for Arduino
• Working SIM with balance
• DHT11 Temperature & Humidity module (can be use DHT22 or other)
• Jumper wires

Details:

• Humidity and Temperature Sensor Module is based on the DHT-11 Sensor which is a very popular, ultralow cost digital temperature and humidity sensor. It uses a capacitive humidity sensor, and a thermistor to measure the surrounding air temperature. The result is available via a digital signal on the data pin (no analog input pins needed). Its fairly simple to use, but requires careful timing to grab data. The only real downside of this sensor is you can only get new data from it once every 2 seconds. But, for most applications this is not an issue at all. The DHT11 is a low cost version of the DHT-22 sensor. The more expensive DHT22 is more precise, more accurate and works in a wider temperature and humidity range.

Specifications:

• 3.0V to 5.5V Operating Voltage
• 1-2.5mA measuring current
• 100-150 µA standby current
• Humidity from 20-80% humidity readings with 5% accuracy
• 0-50°C temperature readings ±2°C accuracy
• Uses Single wire to send the data
• Size 28mm x 12mm x 8mm

Module Interface Description:

• VCC: connect to positive 3.3-5V
• GND: connect to negative
• S: Digital Output Signal

Library Link:

• SIM900.h

https://www.youtube.com/redirect?v=Y30iEOxl1To&event=video_description&q=https%3A%2F%2Fgithub.com%2Fadafruit%2FDHT-sensor-library&redir_token=89pRp-UJ_YU9vUXYHwaa_gKBEsJ8MTUwOTM4NDk3MEAxNTA5Mjk4NTcw

• DHT.h

https://www.youtube.com/redirect?v=Y30iEOxl1To&event=video_description&q=http%3A%2F%2Fwww.tinyosshop.com%2Fdatasheet%2FGSM_GPRS_GPS_Shield_GSMSHIELD.rar&redir_token=89pRp-UJ_YU9vUXYHwaa_gKBEsJ8MTUwOTM4NDk3MEAxNTA5Mjk4NTcw

Code:

#include "SIM900.h"

#include <SoftwareSerial.h>

#include "call.h"

#include <DHT.h>

#include "sms.h"

int gsmTx = 2; // TX- pin to Arduino Pin D2

int gsmRx = 3; // RX- pin to Arduino Pin D3

SMSGSM sms;

#define DHTPIN 7 //DHT Output Pin connect to Arduino Pin 7

#define DHTTYPE DHT11

CallGSM call;

boolean started=false;

char sms_text[160];

DHT dht(DHTPIN, DHTTYPE);

void setup()

{

pinMode(DHTPIN, INPUT);

dht.begin();

Serial.begin(9600);

if (gsm.begin(9600))

{

Serial.println("\nstatus=READY");

started=true;

}

else

Serial.println("\nstatus=IDLE");

}

void loop()

{

float humidity, temperature;

String smsText ="";

switch (call.CallStatus())

{

case CALL_NONE: // Nothing is happening

break;

case CALL_INCOM_VOICE : // Yes! Someone is calling us

Serial.println("RECEIVING1 CALL");

delay(1000);

call.HangUp();

delay(3000);

Serial.println("CALL1 HANGUP");

humidity = dht.readHumidity();

temperature = dht.readTemperature();

delay(2000);

smsText = "Temperature: "+String(temperature,1)+"C Humidity: "+String(humidity,1)+"%";

smsText.toCharArray(sms_text,160);

//Serial.println(smsText);

sms.SendSMS("+91XXXXXXXXXX",sms_text);// Set your mobile No. on which you receive the SMS

break;

case CALL_COMM_LINE_BUSY: // In this case the call would be established

Serial.println("TALKING. Line busy.");

break;

}

delay(1000);

}