Interfacing the GPS module

The GPS I plan to interface is an EM-406A module that I had laying around. I want to mount the GPS module away from the Arduboat box, so I had to extend the cable. I cut off the connector cable socket in the other end of the GPS, and soldered on a shielded extension cable with a length of about 150 cm.

Before integrating the GPS with the Arduino Mega, I wanted to test it on my Arduino Duemillanove. I connected the pins on the GPS to my Arduino Duemillanove in the following way:

• Pin 1+5: Ground (I connected this also the the cable shielding)
• Pin 2: +5V
• Pin 3: A4
• Pin 4: Not used
• Pin 5: Not used
• Pin 6 (grey cable): Not used

I then created a small Arduino that simply prints the incoming data to the screen:

#include <SoftwareSerial.h>

SoftwareSerial _gpsSerial(4,5);

void setup()

{

  Serial.begin(4800);

  _gpsSerial.begin(4800);

}

void loop()

{

  if (_gpsSerial.available())

  {

    Serial.write(_gpsSerial.read());

  }

}

I uploaded the program to the Arduino Duemillanove, and started the Arduino Serial Monitor, ensuring that the baudrate was set to 4800 in the monitor window. I placed the GPS module near my window, to ensure a good receiption. In the beginning I received almost empty NMEA strings from the GPS module, but after a few minutes the GPS was calibrated correctly, and started outputting data as expected: