Soil Moisture Measurement System

The following system measures the Soil Moisture percentage and it will be notified by two ways. i.e In section 6.2 measured quantity will be displayed on the LCD display, and in 6.3 it is sent to the given mobile phone number as an SMS.

6.1. Interfacing soil moisture sensor with Arduino

            In order to receive the sensed data from the soil moisture sensor to arduino, power supply of 5V is provided from arduino by connecting Vcc of sensor to 5V of arduino and GND of sensor to GND of arduino. Readings are retrieved at analog pin of arduino by connecting A0 of soil moisture sensor to any analog pin of arduino. Those retrieved values are displayed via LCD display or sent as SMS using GSM-SIM 900.

Soil moisture sensor	Arduino
Vcc	5V
Gnd	Gnd
A0	A0
D0	NC

6.2. Soil moisture sensor with LCD

6.2.1. Circuit diagram:

6.2.2. Arduino program:

#include <LiquidCrystal.h>

LiquidCrystal lcd(12, 11, 2, 3, 4, 5);

int soil=0;

// the setup routine runs once when you press reset:

void setup()

{

  // initialize serial communication at 9600 bits per second:

  Serial.begin(9600);

  lcd.begin(16,2);

}

// the loop routine runs over and over again forever:

void loop() {

  lcd.clear();

  // read the input on analog pin 0:

  int sensorValue = analogRead(A0);

  sensorValue = constrain(sensorValue, 485, 1023);

  // print out the value you read:

  //Serial.println(sensorValue);

  //map the value to a percentage

  soil = map(sensorValue, 485, 1023, 100, 0);

  // print out the soil water percentage you calculated:

  Serial.print(soil);

  Serial.println("%");

  lcd.print("Soil Moisture");

  lcd.setCursor(0, 1);

  lcd.print(soil);

  lcd.print("  %");

  delay(1000);        // delay in between reads for stability

}

6.2.3.  Output of the System                                            

6.3. Soil moisture sensor with GSM-SIM 900

6.3.1. Circuit diagram:

6.3.2. Arduino program:

int soil=0;

// the setup routine runs once when you press reset:

void setup() {

  // initialize serial communication at 9600 bits per second:

  Serial.begin(9600);

  Serial1.begin(9600); //Baud rate of the GSM/GPRS Module

  Serial1.print("\r");

}

// the loop routine runs over and over again forever:

void loop() {

  // read the input on analog pin 0:

  int sensorValue = analogRead(A0);

  sensorValue = constrain(sensorValue, 485, 1023);

  // print out the value you read:

  //Serial.println(sensorValue);

  //map the value to a percentage

  soil = map(sensorValue, 485, 1023, 100, 0);

  // print out the soil water percentage you calculated:

  Serial.print(soil);

  Serial.println("%");

  delay(1000);        // delay in between reads for stability

  Serial1.print("AT+CMGF=1\r");

  delay(1000);

  Serial1.print("AT+CMGS=\"+919542081456\"\r"); //Number to which you want to  send the SMS

  delay(1000);

  Serial1.print(soil); //The text of the message to be sent

  Serial1.print("%");

  delay(1000);

  Serial1.write(0x1A);

  delay(20000);

}

Please Let me know if you have any queries?