GPS

GPS stands for Global Positioning System.

A GPS module receives signals from several GPS satellites orbiting the earth, and determines the modules' location in longitude and latitude.

Typical GPS modules output what is known as an NMEA (National Marine Electronic Association) string at 4800 baud. They follow this format:

$GPGLL,1234.56,S,1357.91,W,25516.36,A  Where: 1234.56     is the longitude S                     is indication of North/South of the equator 1357.91      is the latitude W                   is indication of East/West of the prime meridian 25516.36  is the current time, (02 hours : 55 minutes : 16 seconds . 36 miliseconds) reference to zulu time A                    Data valid