How to Use EM408_CON: Examples, Pinouts, and Specs

The EM408_CON is a compact, high-performance GPS receiver module manufactured by GlobalSat (Part ID: EM-408). This module is designed for seamless integration into a wide range of electronic projects, offering precise positioning data with support for multiple satellite systems, including GPS, WAAS, and EGNOS. Its small form factor and robust performance make it ideal for applications such as navigation, asset tracking, and location-based services.

• Vehicle navigation systems
• Personal tracking devices
• Drones and UAVs
• IoT devices requiring geolocation
• Outdoor sports and fitness equipment

The EM408_CON module has a 6-pin interface for power, communication, and control. Below is the pinout:

1. Power Supply: Connect the VCC pin to a regulated 3.3V or 5.0V power source and the GND pin to the ground of your circuit.
2. UART Communication:
   • Connect the TXD pin of the EM408_CON to the RX pin of your microcontroller or UART interface.
   • Connect the RXD pin of the EM408_CON to the TX pin of your microcontroller or UART interface.
3. PPS Signal: The PPS pin outputs a 1 Hz pulse for precise timing applications. This is optional and can be left unconnected if not used.
4. Antenna: Attach an active GPS antenna to the module's antenna connector for optimal satellite reception.

• Ensure the module has a clear view of the sky for accurate GPS signal reception.
• Avoid placing the module near sources of electromagnetic interference (e.g., high-frequency circuits or motors).
• Configure the baud rate and update rate as needed using NMEA commands.
• Use a level shifter if interfacing with a 5V microcontroller to avoid damaging the module's 3.3V UART pins.

Below is an example of how to connect the EM408_CON to an Arduino UNO and read GPS data:

#include <SoftwareSerial.h>

// Define RX and TX pins for SoftwareSerial
SoftwareSerial gpsSerial(10, 11); // RX = Pin 10, TX = Pin 11

void setup() {
  Serial.begin(9600); // Initialize Serial Monitor
  gpsSerial.begin(4800); // Initialize GPS module at 4800 bps
  Serial.println("EM408_CON GPS Module Initialized");
}

void loop() {
  // Check if data is available from the GPS module
  while (gpsSerial.available()) {
    char c = gpsSerial.read(); // Read one character from GPS
    Serial.print(c); // Print the character to Serial Monitor
  }
}

• The default baud rate of the EM408_CON is 4800 bps. Adjust the gpsSerial.begin() value if you change the baud rate.
• Use an external GPS antenna for better signal reception.

1. No GPS Data Output

   • Cause: Incorrect wiring or baud rate mismatch.
   • Solution: Double-check the connections and ensure the baud rate matches the module's configuration.

2. Poor GPS Signal

   • Cause: Obstructed view of the sky or interference.
   • Solution: Place the module outdoors or near a window with a clear view of the sky. Use an active GPS antenna.

3. Module Not Powering On

   • Cause: Insufficient power supply.
   • Solution: Ensure the power source provides a stable 3.3V to 5.0V and sufficient current (at least 50 mA).

4. PPS Signal Not Detected

   • Cause: PPS pin not connected or misconfigured.
   • Solution: Verify the PPS pin connection and check the module's configuration.

• Q: Can the EM408_CON be used indoors?
  A: While the module can operate indoors, GPS signal reception may be weak or unavailable. Use it outdoors or near a window for best results.

• Q: How do I change the baud rate?
  A: The baud rate can be changed using specific NMEA configuration commands. Refer to the manufacturer's documentation for details.

• Q: Is the module compatible with 5V logic?
  A: The module's UART pins operate at 3.3V logic. Use a level shifter if interfacing with a 5V microcontroller.

• Q: What is the purpose of the PPS pin?
  A: The PPS (Pulse Per Second) pin provides a precise 1 Hz timing signal, useful for time synchronization in applications like time servers.

This concludes the documentation for the EM408_CON GPS module. For further details, refer to the manufacturer's datasheet or contact GlobalSat support.