RGPSD012 Semtech, RGPSD012 Datasheet - Page 9

• Manufacturer Part Number: RGPSD012
• Description: KIT EVAL FOR RGPSM002
• Manufacturer: Semtech
• Type: GPSr

Specifications of RGPSD012

• For Use With/related Products: RGPSM002
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

sending the appropriate proprietary NMEA commands defined in Section 5.4 below. Note these temporary settings will
be lost the next time the main supply VCC is turned off.
5.3
The RGPSM002 supports NMEA-0183. Brief descriptions of the output messages are provided below.
5.3.1
Semtech receivers use the standard output messages listed in Table 6:
After a reset condition occurs, as defined above, the default setting for NMEA sentences is GGA, GSA, GSV and RMC,
with update every second. This default setting can be modified in the Default Parameters Table (parameters #3 to #9) in
Flash, and can also be overridden with the PXEMaNM manufacturer specific sentence defined hereafter.
Note on Latitude and Longitude format in NMEA sentences
The standard, variable-length, NMEA format for Latitude is ddmm.mmmm, where “dd” are 2 digit characters for the
degrees, “mm” are 2 digit characters for the minutes, and the “.mmmm” are n digits for the decimal value of the minutes.
So 6 degree 9.789 minutes is represented by the string “0609.789”, “0609.7890”, or “0609.78900”. Similarly, the
standard, variable-length, NMEA format for Longitude is dddmm.mmmm, where “ddd” are 3 digit characters for the
degrees, “mm” are 2 digit characters for the minutes, and the “.mmmm” are n digits for the decimal value of the minutes.
So 45 degrees 6.129 minutes is represented by the string “04506.129”, “04506.1290”, or “04506.12900”
5.3.2
Description: This message reports the global positioning system fixed data, as shown in Table 7.
© Semtech 2005
NMEA STANDARD MESSAGE SET SPECIFICATION
NMEA Standard Sentences
GGA —Global Positioning System Fixed Data
Name
Message ID
UTC Position
Latitude
N/S Indicator
Longitude
E/W Indicator
Position Fix Indicator
Satellites Used
HDOP
MSL Altitude
Units
Geoid Separation
Units
Age of Diff. Corr.
Diff. Ref. Station ID
Checksum
<CR><LF>
1
does not support geoid corrections. Values are WGS-84 ellipsoid heights.
NMEA
GGA
GLL
GSA
GSV
RMC
VTG
ZDA
1
1
Message Description
Global positioning system fixed data
Geographic position – latitude/longitude
GNSS DOP and active satellites
GNSS satellites in view
Recommended minimum specific GNSS data
Course over ground and ground speed
Time & Date
Example
$GPGGA
161229.487
3723.2475
N
12158.3416
W
1
07
1.0
9.0
M
M
0000
*18
Table 6. NMEA-0183 Messages
Table 7. GGA Data Format
Units
Meters
Meters
Meters
Meters
Second
9
End of message termination
Description
GGA protocol header
hhmmss.sss
ddmm.mmmm
N = north or S = south
dddmm.mmmm
E = east or W = west
See Table 8
Range 0 to 12
Horizontal Dilution of Precision
Null fields when DGPS is not used
RGPSM002
GPS Receiver
www.semtech.com