This project involves using an Arduino board to interface with a GPS module and an RTC (Real-Time Clock) module to calculate and measure the time difference between the two time sources. The GPS provides an accurate UTC time, while the RTC (DS3231) provides local time stored on the board. The project calculates the difference in seconds between the GPS time and RTC time and prints the result every 10 seconds to the Serial Monitor.

  1. Arduino Board (e.g., Arduino Nano)

    • Used as the central controller for the project. It processes data from both the GPS and RTC modules.

  2. GPS Module (e.g., u-blox NEO-8M)

    • Provides UTC time data. This is a satellite-based time source, offering a very high degree of accuracy.

    • The GPS module communicates with the Arduino via the library, using two pins for communication (TX and RX).

  3. RTC Module (DS3231)

    • A Real-Time Clock module that provides local time (set by the user) and keeps track of time accurately even when the Arduino is powered off.

    • Communicates with the Arduino via I2C (SDA and SCL pins).

  4. Wiring and Pin Connections

    • GPS Module to Arduino:

      • RX pin of GPS to pin 4 on Arduino (configured for software serial reception).

      • TX pin of GPS to pin 3 on Arduino (configured for software serial transmission).

    • RTC Module to Arduino:

      • SDA pin of RTC to pin A4 (SDA) on Arduino Nano.

      • SCL pin of RTC to pin A5 (SCL) on Arduino Nano.

How It Works:

  1. GPS Module Interaction:

    • The GPS module is used to get the current UTC time (in hours, minutes, and seconds).

    • The GPS module sends $GPRMC NMEA sentences, from which we extract the time data.

    • The extracted time is converted into seconds since midnight to facilitate easy comparison.

  2. RTC Module Interaction:

    • The DS3231 RTC module keeps track of the local time.

    • The time from the RTC is retrieved in seconds (from midnight) to be compared with the GPS time.

  3. Time Difference Calculation:

    • The Arduino receives both GPS time and RTC time.

    • It calculates the difference between the two times, which indicates the offset (in seconds) between the GPS and RTC.

    • The time difference is printed to the Serial Monitor.

  4. Output:

    • Every 10 seconds, the time difference between the GPS and RTC modules is calculated and displayed on the Serial Monitor in seconds.

    • The serial output shows the GPS time, RTC time, and the time difference.