Gps - Libelium Waspmote Technical Manual

25. GPS

Waspmote can integrate a GPS receiver which allows to know the exact location of the mote anytime. Thus, the
exact position of the mote can be obtained and even the current time and date, to synchronize the Waspmote
internal clock (RTC) with the real time. Besides, data can be geolocated on a map.
Figure: GPS module
The GPS module gives us information about:
latitude
•
longitude
•
altitude
•
speed
•
direction
•
date/time
•
ephemeris
•
The functions implemented in the API allow this information to be extracted simply, calling functions such as:
{
GPS.getAltitude();
GPS.getSpeed();
GPS.getLongitude();
GPS.getLatitude();
}
The GPS receiver uses the UART_1 to communicate with the microcontroller, sharing this UART with the GPRS,
3G, , NB-IoT / Cat-M or 4G modules. As up to 2 modules share this UART, a multiplexer has been enabled in order
to select the module with which we wish to communicate at any time. This is not a problem; since all actions are
sequential, in practice there is parallel availability of both devices.
The GPS starts up by default at 4800 bps. This speed can be increased using the library functions that have been
designed for controlling and managing the module.
The GPS receiver has 2 operational modes: NMEA (National Marine Electronic Association) mode and binary
mode. NMEA mode uses statements from this standard to obtain location, time and date. The binary mode is
based on the sending of structured frames to establish communication between the microcontroller and the GPS
receiver, i.e. to read/set ephemeris.
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GPS
v8.2