MDEV-GPS-RM datasheet(9/27 Pages) LINX

9 / 27 page

–

NMEA Output Messages

The following sections outline the data structures of the various NMEA

messages that are supported by the module. By default, the NMEA

commands are output at 9,600bps, 8 data bits, 1 start bit, 1 stop bit, and

no parity.

Six messages are output at a 1Hz rate by default. The ZDA message is

supported, but disabled by default. These messages are shown in Figure 8.

Details of each message and examples are given in the following sections.

NMEA Output Messages

Name

Description

GGA

Contains the essential fix data which provide location and accuracy

GLL

Contains just position and time

GSA

Contains data on the Dilution of Precision (DOP) and which satellites are used

GSV

Contains the satellite location relative to the receiver and its signal to noise

ratio. Each message can describe 4 satellites so multiple messages may be

output depending on the number of satellites being tracked.

RMC

Contains the minimum data of time, position, speed and course

VTG

Contains the course and speed over the ground

ZDA

Contains the date and time

Figure 8: NMEA Output Messages

GGA – Global Positioning System Fix Data

Figure 9 contains the values for the following example:

$GPGGA,053740.000,2503.6319,N,12136.0099,E,1,08,1.1,63.8,M,15.2,M,,0000*64

Global Positioning System Fix Data Example

Name

Example

Units

Description

Message ID

$GPGGA

GGA protocol header

UTC Time

053740.000

hhmmss.sss

Latitude

2503.6319

ddmm.mmmm

N/S Indicator

N=north or S=south

Longitude

12136.0099

dddmm.mmmm

E/W Indicator

E=east or W=west

Position Fix Indicator

See Figure 10

Satellites Used

Range 0 to 33

HDOP

1.1

Horizontal Dilution of Precision

MSL Altitude

63.8

meters

Units

meters

Geoid Separation

15.2

meters

Units

meters

Age of Diff. Corr.

second

Null fields when DGPS is not used

Diff. Ref. Station

0000

Checksum

*64

End of message termination

Position Indicator Values

Value

Description

Fix not available or invalid

GPS SPS Mode, fix valid

2–5

Not supported

Dead Reckoning Mode, fix valid (requires external hardware)

Figure 9: Global Positioning System Fix Data Example

Figure 10: Position Indicator Values

Note: The GLL and VTG messages are enabled by default on modules

with date code 1612 and later. They were disabled by default on earlier

modules.

MDEV-GPS-RM Datasheet(PDF) 9 Page - Linx Technologies

MDEV-GPS-RM Datasheet(HTML) 9 Page - Linx Technologies

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27

Datasheet Download

Link URL