Circuit Documentation

Summary

This circuit is designed to read GPS data from a NEO 6M module and send the current location to a designated phone number via a SIM800L module when a button is pressed twice within a short interval. The circuit is controlled by an Arduino UNO microcontroller.

Component List

SIM800L

• Description: GSM/GPRS module used for sending SMS.
• Pins: NET, VCC, RST, RXD, TXD, GND, RING, DTR, MIC+, MIC-, SPK+, SPK-

Arcade Button (white)

• Description: A simple push button used to trigger the location sending.
• Pins: NO, COM

Arduino UNO

• Description: Microcontroller used to control the circuit.
• Pins: UNUSED, IOREF, Reset, 3.3V, 5V, GND, Vin, A0, A1, A2, A3, A4, A5, SCL, SDA, AREF, D13, D12, D11, D10, D9, D8, D7, D6, D5, D4, D3, D2, D1, D0

Battery 18650

• Description: Power source for the circuit.
• Pins: +, -

Resistor

• Description: 240 Ohms resistor used for current limiting.
• Pins: pin1, pin2
• Properties: Resistance: 240 Ohms

GPS NEO 6M

• Description: GPS module used to get the current location.
• Pins: VCC, RX, TX, GND

Wiring Details

SIM800L

• VCC: Connected to Battery 18650 (+)
• RXD: Connected to Arduino UNO (D12)
• TXD: Connected to Arduino UNO (D11)
• GND: Connected to Battery 18650 (-)

Arcade Button (white)

• NO: Connected to Resistor (pin1)
• COM: Connected to Arduino UNO (3.3V)

Arduino UNO

• D12: Connected to SIM800L (RXD)
• D11: Connected to SIM800L (TXD)
• GND: Connected to Resistor (pin1) and GPS NEO 6M (GND)
• 3.3V: Connected to Arcade Button (COM)
• 5V: Connected to GPS NEO 6M (VCC)
• D3: Connected to GPS NEO 6M (RX)
• D4: Connected to GPS NEO 6M (TX)
• D5: Connected to Resistor (pin2)

Battery 18650

• +: Connected to SIM800L (VCC)
• -: Connected to SIM800L (GND)

Resistor

• pin1: Connected to Arduino UNO (GND) and Arcade Button (NO)
• pin2: Connected to Arduino UNO (D5)

GPS NEO 6M

• VCC: Connected to Arduino UNO (5V)
• RX: Connected to Arduino UNO (D3)
• TX: Connected to Arduino UNO (D4)
• GND: Connected to Arduino UNO (GND)

Code Documentation

/*
 * This Arduino Sketch reads GPS data from a NEO 6M module and sends the current
 * location to a designated phone number via a SIM800L module when a button is
 * pressed twice within a short interval.
 */

#include <SoftwareSerial.h>

// Pin definitions
#define GPS_RX_PIN 3
#define GPS_TX_PIN 4
#define SIM800L_RX_PIN 12
#define SIM800L_TX_PIN 11
#define BUTTON_PIN 5

// Create software serial ports
SoftwareSerial gpsSerial(GPS_TX_PIN, GPS_RX_PIN);
SoftwareSerial sim800lSerial(SIM800L_TX_PIN, SIM800L_RX_PIN);

// Variables for button press detection
unsigned long lastButtonPressTime = 0;
unsigned long buttonPressInterval = 500; // 500 ms
int buttonPressCount = 0;

void setup() {
  // Initialize serial communication
  Serial.begin(9600);
  gpsSerial.begin(9600);
  sim800lSerial.begin(9600);

  // Initialize button pin
  pinMode(BUTTON_PIN, INPUT);

  // Initialize SIM800L
  initializeSIM800L();
}

void loop() {
  // Check for button press
  if (digitalRead(BUTTON_PIN) == HIGH) {
    unsigned long currentTime = millis();
    if (currentTime - lastButtonPressTime < buttonPressInterval) {
      buttonPressCount++;
    } else {
      buttonPressCount = 1;
    }
    lastButtonPressTime = currentTime;
  }

  // If button is pressed twice, send location
  if (buttonPressCount == 2) {
    String location = getGPSLocation();
    sendLocationSMS(location);
    buttonPressCount = 0;
  }
}

void initializeSIM800L() {
  // Send initialization commands to SIM800L
  sim800lSerial.println("AT");
  delay(1000);
  sim800lSerial.println("AT+CMGF=1"); // Set SMS to text mode
  delay(1000);
}

String getGPSLocation() {
  String gpsData = "";
  while (gpsSerial.available()) {
    char c = gpsSerial.read();
    gpsData += c;
  }
  // Parse GPS data to extract location
  // This is a simplified example, actual parsing will depend on GPS data format
  String latitude = "N/A";
  String longitude = "N/A";
  int latIndex = gpsData.indexOf("$GPGGA");
  if (latIndex != -1) {
    latitude = gpsData.substring(latIndex + 18, latIndex + 27);
    longitude = gpsData.substring(latIndex + 30, latIndex + 40);
  }
  return "Lat: " + latitude + ", Lon: " + longitude;
}

void sendLocationSMS(String location) {
  sim800lSerial.print("AT+CMGS=\"+9779861806001\""); // Replace with actual phone number
  delay(1000);
  sim800lSerial.print(location);
  delay(1000);
  sim800lSerial.write(26); // ASCII code for CTRL+Z to send SMS
  delay(1000);
}

This code initializes the GPS and SIM800L modules, reads GPS data, and sends the location via SMS when the button is pressed twice within a short interval.