Weather Monitoring System using PIC Microcontroller

Introduction

In today's world, monitoring environmental conditions such as temperature, humidity, and atmospheric pressure is crucial for various applications, including agriculture, home automation, and industrial control systems. A weather monitoring system helps gather data and analyze weather patterns, which can be vital for decision-making processes. This article will guide you through building a simple yet effective weather monitoring system using a PIC microcontroller.

of the System

The weather monitoring system we will create utilizes a PIC microcontroller to interface with sensors that measure temperature, humidity, and atmospheric pressure. The data collected from these sensors will be displayed on an LCD screen and can also be stored or transmitted wirelessly for remote monitoring.

Components Required

1. PIC Microcontroller (e.g., PIC16F877A) - This microcontroller will serve as the brain of the system, processing the data received from the sensors.

2. DHT11/DHT22 Sensor - Used for measuring temperature and humidity.

3. BMP180/BMP280 Sensor - Used for measuring atmospheric pressure.

4. 16x2 LCD Display - Displays the collected data for easy viewing.

5. Resistors, Capacitors, and Potentiometer - Basic components for interfacing and setting up the circuit.

6. Breadboard and Connecting Wires - For assembling the components.

7. Power Supply - To power the circuit.

Circuit Diagram

Below is a basic circuit diagram illustrating how the components are connected to the PIC microcontroller:

[Include a simple circuit diagram here. Since text is limited, imagine a typical setup where the DHT11 sensor is connected to one of the digital pins, the BMP180 sensor communicates via I2C, and the LCD is connected to another set of digital pins. You can use Proteus or Fritzing to create the actual circuit diagram.]

Working Principle

The PIC microcontroller is programmed to read data from the DHT11/DHT22 sensor for temperature and humidity and from the BMP180/BMP280 sensor for atmospheric pressure. The collected data is then processed and displayed on the 16x2 LCD screen. The microcontroller continuously monitors these parameters, providing real-time weather updates.

Step-by-Step Implementation

Step 1: Setting Up the Environment

Before starting with the hardware, ensure you have the necessary software tools installed:

• MPLAB X IDE - Integrated Development Environment for writing and debugging code for PIC microcontrollers.

• XC8 Compiler - A compiler for converting C code into a hex file that the PIC microcontroller can understand.

Step 2: Writing the Code

Start by initializing the PIC microcontroller and setting up the necessary peripherals.

Code Outline:

#include <xc.h>

#include "lcd.h"       // Include LCD library

#include "DHT11.h"     // Include DHT11 library

#include "BMP180.h"    // Include BMP180 library

#define _XTAL_FREQ 20000000  // Define the crystal frequency (20MHz)

// Configuration bits for PIC16F877A

#pragma config FOSC = HS   // High-Speed Oscillator

#pragma config WDTE = OFF  // Watchdog Timer Disabled

#pragma config PWRTE = OFF // Power-up Timer Disabled

#pragma config BOREN = ON  // Brown-out Reset Enabled

#pragma config LVP = OFF   // Low Voltage Programming Disabled

#pragma config CPD = OFF   // Data EEPROM Memory Code Protection Disabled

#pragma config WRT = OFF   // Flash Program Memory Write Enable

#pragma config CP = OFF    // Flash Program Memory Code Protection Disabled

void main(void) {

    // Initialize the LCD

    Lcd_Init();

    Lcd_Clear();

    // Initialize the DHT11 sensor

    DHT11_Init();

    // Initialize the BMP180 sensor

    BMP180_Init();

    // Variable declarations

    float temperature, humidity, pressure;

    while(1) {

        // Read temperature and humidity from DHT11

        temperature = DHT11_ReadTemperature();

        humidity = DHT11_ReadHumidity();

        // Read pressure from BMP180

        pressure = BMP180_ReadPressure();

        // Display the data on LCD

        Lcd_Set_Cursor(1, 1);

        Lcd_Write_String("Temp: ");

        Lcd_Write_Float(temperature);

        Lcd_Write_String("C");

        Lcd_Set_Cursor(2, 1);

        Lcd_Write_String("Hum: ");

        Lcd_Write_Float(humidity);

        Lcd_Write_String("%");

        Lcd_Set_Cursor(3, 1);

        Lcd_Write_String("Pres: ");

        Lcd_Write_Float(pressure);

        Lcd_Write_String("hPa");

        __delay_ms(2000);  // Wait for 2 seconds before the next reading

    }

}

Step 3: Interfacing the Sensors

• DHT11/DHT22 Sensor: Connect the VCC and GND pins of the DHT11 sensor to the power supply. The data pin should be connected to one of the digital I/O pins of the PIC microcontroller (e.g., RA0).

• BMP180/BMP280 Sensor: Since this sensor uses I2C communication, connect the SDA and SCL pins to the respective I2C pins on the PIC microcontroller (e.g., RC3 for SCL and RC4 for SDA).

• LCD Display: Connect the LCD to the microcontroller following standard LCD interfacing techniques, ensuring the data pins (D4-D7) and control pins (RS, RW, EN) are correctly wired.

Step 4: Compiling and Uploading the Code

• Write the code in MPLAB X IDE.

• Compile the code using the XC8 compiler to generate a hex file.

• Upload the hex file to the PIC microcontroller using a programmer (e.g., PICkit 3).

Step 5: Testing the System

Power up the circuit and observe the LCD screen. It should display the current temperature, humidity, and atmospheric pressure. Ensure the readings are accurate by comparing them with a standard weather monitoring device.

Applications

• Home Automation: Monitor indoor environmental conditions for a smart home setup.

• Agriculture: Track weather conditions to optimize irrigation and crop management.

• Industrial Monitoring: Maintain ideal environmental conditions in sensitive manufacturing processes.

Conclusion

Building a weather monitoring system using a PIC microcontroller is an excellent way to get hands-on experience with microcontroller programming and sensor interfacing. This project can be expanded by adding more sensors, storing data for long-term analysis, or integrating wireless communication for remote monitoring. The system's versatility makes it applicable in numerous fields, from home automation to industrial control.

By following the steps outlined in this article, you can successfully create your own weather monitoring system and tailor it to your specific needs.

Want us to guide you through your project or make the project for you ?

Order Projects

Create Various Projects

Check out our Free Arduino Projects Playlist - Arduino Projects 

Check out our Free Raspberry Pi Projects Playlist - Raspberry Pi Projects 

Check out our Free TinkerCAD Projects Playlist - TinkerCAD Projects 

Check out our Free IoT Projects Playlist - IoT Projects 

Check out our Free Home Automation Projects Playlist - Home Automation Projects 

Check out our Free NodeMCu Projects Playlist - NodeMCu Projects