RGPSM202
SlimGPS™ Receiver
RGPSM202
SlimGPS™ - GPS Receiver
OEM Module
GENERAL DESCRIPTION
KEY FEATURES
The RGPSM202 SlimGPS features the well
®
established FirstGPS architecture. This autonomous
GPS receiver solution provides high performances in
terms of position and speed accuracy as well as
sensitivity and tracking capabilities in urban conditions.
•
Small low profile form factor and low cost solution.
Surface mount, ready-to-plug solution. Drop-in
direct digital interface
•
Sensitivity to -143 dBm tracking
•
Position accuracy: < 5m CEP (50%) without SA
(horizontal)
•
Warm Start is under 32 seconds (50%)
•
Hot Start is under 12 seconds (50%)
•
Ultra low power: 25 mA @ 3V full power, 3
additional low power modes
•
Embedded ARM7TDMI
•
Ready-to-plug solution, fully autonomous PVT
solution. Easily integrated into existing systems
•
On-board RAM for GPS navigation data, on-board
Flash memory back-up
The solution enables small form factor package. It is
designed to simplify the embedded system integration
process.
These modules are based on the Semtech XE1610
Ultra Low Power GPS chipset.
APPLICATIONS
•
In-vehicle navigation systems
•
Car accessories
•
Asset management/tracking
•
Fleet management
•
PPS output
•
Palmtop, Laptop, PDA
•
Bidirectional NMEA interface
•
Location Based Services enabled devices
•
•
Handheld receivers
Real Time Clock with separate back-up power
supply
REFERENCE
RGPSM202 – 16M Flash version
Rev 1 August 2005
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1
RGPSM202
SlimGPS™ Receiver
Table of Contents
FIRSTGPS ARCHITECTURE HIGHLIGHTS................................................................................................................3
1.1
Industry Leading GPS Performance......................................................................................................................3
1.2
Low Power .............................................................................................................................................................3
1.3
RGPSM202 SlimGPS Receiver Highlights............................................................................................................3
2 FUNCTIONAL BLOCK DIAGRAM ................................................................................................................................3
1
3
PIN DESCRIPTION.......................................................................................................................................................4
4
TECHNICAL CHARACTERISTICS...............................................................................................................................4
4.1
Specifications.........................................................................................................................................................4
4.2
Physical Characteristics.........................................................................................................................................5
4.3
Mechanical Interface..............................................................................................................................................5
4.4
Production Issues ..................................................................................................................................................6
4.4.1
Proposed Customer Solder Profile.................................................................................................................6
INTERFACE DEFINITION, PRINCIPLES OF OPERATION ........................................................................................6
5.1
Data/RF Interface...................................................................................................................................................6
5.2
Operating Modes ...................................................................................................................................................8
5.2.1
Operating the GPS receiver in a basic “stand-alone” configuration...............................................................8
5.2.2
Operating the GPS receiver in a basic “serial, bidirectional” configuration....................................................9
5.3
NMEA Standard Message Set Specification .......................................................................................................10
5.3.1
NMEA Standard Sentences..........................................................................................................................10
5.3.2
GGA —Global Positioning System Fixed Data ............................................................................................10
5.3.3
GLL—Geographic Position - Latitude/Longitude..........................................................................................11
5.3.4
GSA—GNSS DOP and Active Satellites......................................................................................................11
5.3.5
GSV—GNSS Satellites in View ....................................................................................................................12
5.3.6
RMC—Recommended Minimum Specific GNSS Data ................................................................................13
5.3.7
VTG—Course Over Ground and Ground Speed .........................................................................................13
5.3.8
ZDA—Time & Date .......................................................................................................................................14
5.3.9
GPQ—NMEA Sentence Query.....................................................................................................................14
5.4
NMEA Specific Sentences...................................................................................................................................15
5.4.1
DI – Diagnostic Message..............................................................................................................................15
5.4.2
TF—Quick Test ............................................................................................................................................15
5.4.3
NM – Sentence Mask and Automatic Output Rate ......................................................................................16
5.4.4
PS – Pulse-Per-Second Configuration .........................................................................................................17
5.4.5
PT – Port Configuration ................................................................................................................................17
5.4.6
RT – Reset the Receiver / Start-Stop FirstGPS ...........................................................................................17
5.4.7
VR – Version Information .............................................................................................................................18
5.4.8
GS – Geodetic System Configuration ..........................................................................................................18
5.4.9
LP – Power Save Mode................................................................................................................................19
5.4.10 TR – Transparent Mode ..............................................................................................................................19
5.5
GPS Data Back-up ..............................................................................................................................................22
5.6
Real Time clock ...................................................................................................................................................22
5.7
Split Search Mode................................................................................................................................................22
5.8
Hardware Reset and System Watchdog .............................................................................................................22
DEFAULT SETTINGS.................................................................................................................................................23
6.1
GPS Engine Configuration...................................................................................................................................24
6.1.1
Receiver configuration..................................................................................................................................24
6.1.2
Filter configuration ........................................................................................................................................24
6.1.3
Offset configuration ......................................................................................................................................24
6.1.4
Application settings.......................................................................................................................................24
APPLICATION INFORMATION ..................................................................................................................................24
7.1
Active Antenna.....................................................................................................................................................24
EXHIBIT A ...................................................................................................................................................................25
5
6
7
8
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RGPSM202
SlimGPS™ Receiver
1
FIRSTGPS ARCHITECTURE HIGHLIGHTS
1.1
-
INDUSTRY LEADING GPS PERFORMANCE
Builds on high performance FirstGPS core
Satellite signal tracking engine to perform GPS acquisition and tracking functions without CPU intervention
Sensitivity: to -143 dBm tracking, urban canyon capability
Position accuracy: < 5m CEP (50%) without SA (horizontal)
Warm Start is under 32 seconds (50%)
Hot Start is under 12 seconds (50%)
Timing output accuracy: +/- 100 ns
1.2
LOW POWER
- Ultra low power integrated circuit design, optimized RF and DSP architectures, 25 mA @ 3V tracking/doing fixes
- Further power saving thanks to different power down modes
o Active – power save – RF section, GPS engine, and MCU turned ON, active antenna turned OFF
o Low-power – RF section and GPS engine turned OFF, MCU clock turned ON
o Power down - RF section, GPS engine, and MCU clock turned OFF, main power supply OFF, RTC
running on the back-up supply
1.3
RGPSM202 SLIMGPS RECEIVER HIGHLIGHTS
Embedded AT91 MCU, ARM7TDMI-based
Small form factor
Low cost
Ready-to-plug solution, fully autonomous PVT solution. Easily integrated into existing systems
High signal acquisition & tracking performances
On-board RAM for GPS navigation data. On-board Flash memory (BBFlash) is used to back-up data such as the
Almanac
PPS output
On-board RTC can be supplied by a separate back-up power supply if the main supply is turned off.
Application software can be customized for high volume applications (Flash memory)
-
2
FUNCTIONAL BLOCK DIAGRAM
ANT
Q LPF
RF+
BP
FILTER
BP
FILTER
RF-
XE1610-OEMPVT
APPLICATION
I
RF
DOWNCONVERTER
LNA
Active Antenna
I LPF
Q
MCLKI
SCLK
GPS
BASEBAND
PROCESSOR
RX
TX
API
PVT
BOARD
INTERFACE
FirstGPS
SOFTWARE
RTOS
TCXO
RGPSM202
XE1610-OEMPVT
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RGPSM202
SlimGPS™ Receiver
3
PIN DESCRIPTION
PIN
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
NAME
TDI
TCK
TDO
TMS
RXDA
DGND
TXDA
VCC
DGND
RFGND
RFGND
RFGND
RFGND
RF IN
RFGND
DELPOSN
DGND
VBKP
PPS
DGND
DGND
POSFIX (BT1)
ALMRDY (BT0)
BTM
I
I
O
I
I
O
I
I
O
O
O
I
DESCRIPTION
JTAG pin
JTAG pin
JTAG pin
JTAG pin
Serial Receive Data input
Digital Ground
Serial Transmit Data output
DC Input Power Supply
Digital Ground
RF Ground
RF Ground
RF Ground
RF Ground
RF Input
RF Ground
Delete Initial Position
Digital Ground
RTC Battery back-up
Pulse Per Second output
Digital Ground
Digital Ground
Searching/Position fix indicator / Board Test Mode Sel
Almanac complete & valid / Board Test Mode Sel
Board Test Mode
Table 1 – Pin description
4
4.1
TECHNICAL CHARACTERISTICS
SPECIFICATIONS
Description
Min.
Receiver
Max.
L1, C/A code
Correlators/Channels
Update Rate
Typ.
32/8
1/minute
Satellite Reacquisition Time
1/second
1/second
1 second
HotStart
12 seconds (50%)
Warm Start
32 seconds (50%)
Cold Start
120 seconds (50%)
Tracking Sensitivity
-173 dBW
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RGPSM202
SlimGPS™ Receiver
Description
Min.
Typ.
Power Consumption (VCC) @ 3 V
• Active mode, searching & tracking
• Active - power save mode
• Low-power mode
• Power down mode
Max.
25 mA
20 mA
2.2 mA
2 uA
Voltage Supply VCC
3V
Back Up Voltage Supply VRTCBK
3.3V
1.0V
Output Protocol
3.65V
3.65V
NMEA 0183, v3.0
Position Accuracy
• Horizontal, SA off
• DGPS corrected
Timing output accuracy PPS output (rising edge)
Input voltage – data interface
Low
High
Output voltage, VCC = 3V, I = 2 mA
Low
High
5 meters CEP (50%)
1 meter
- 100 nanosec.
100 nanosec.
0.8V
2.0V
0.4V
2.6V
Table 2 – Electrical specifications
4.2 PHYSICAL CHARACTERISTICS
The dimensions of the RGPSM202 are 38 x 26.5 x 3 mm (approx. 1.49” x 1.04” x 0.12”) drop-in module. Weight is < 6
grams. This device has an operating temperature range between -40 and +85°C
4.3 MECHANICAL INTERFACE
Surface mount, compatible with an SMD assembly line. The figure below shows the foot print for the module. This is a top
view. The pin #1 is on top left. All dimensions in millimeters.
Figure 1 – Footprint for the module
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RGPSM202
SlimGPS™ Receiver
Figure 2 Pad positions and pad details
4.4 PRODUCTION ISSUES
The RGPSM202 module PCB is 1mm thick FR4 board. Its pin out uses castellation joints. It contains BGA components,
has a shield around the edge. It is designed for a secondary re-flowed in customers manufacturing process.
4.4.1
Proposed Customer Solder Profile
The customer solder profile choice is dictated by the solder profile used in the assembly process of the RGPSM202
module. In the Customer Solder Profile, it is recommended to use a solder content of 63% Tin and 37% lead, with a peak
temperature of 200°C, but not exceeding 205°C maximum.
5
INTERFACE DEFINITION, PRINCIPLES OF OPERATION
5.1 DATA/RF INTERFACE
VCC – This is the main power supply
DGND – These are the power and signal ground pins for the digital / MCU section
RFGND – These are the power and signal ground pins for the RF section
VBKP – This is the back-up supply for the on-board hardware Real Time Clock
RXDA – Serial Receive data. This input pin has a pull-up resistor.
TXDA – Serial Transmit data
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RGPSM202
SlimGPS™ Receiver
PPS - The PPS output pin is Pulse per Second highly accurate timing signal generated by the on-board GPS baseband
processor. The PPS signal is available only when the receiver does position fixes. Otherwise its output level is “low”. After
a reset condition, the setting for this port is defined in the Default Parameters Table *, parameter #1. This setting can be
modified with the PXEMaPS manufacturer specific NMEA sentence defined hereafter.
1 second
~ 83 ms.
(*) see the Default Settings section below
Figure 3 – PPS timing diagram
The rising edge of the PPS signal is synchronous with the GPS time.
POSFIX – When in Active mode, this output indicates if the GPS receiver is in search mode (“high”/”low” square wave at
1Hz) or doing position fixes (“low”).
ALMRDY – When in Active mode, this output indicates the on-board Almanac status. Upon start up and whenever the
Almanac data are tested invalid or not up-to-date the output level is “low”. If tested valid and up-to-date the output level is
“high”.
DELPOSN – Delete Initial Position pin. When set “low” for less than 1.5 second, this allows deleting of the initial position in
the RAM portion of the MCU and triggering re-computation of the tracking set. The position will not be deleted if GPS fixes
are already being generated. This function is useful when the initial position is known to be incorrect, for example when the
receiver is powered down, put on a plane, flown 20,000 km, and then warm-started. See timing information in the figure
below. This input pin has a pull-up resistor.
‘Delete Initial Position’ Request
(Delay > 100 ms
<1.5 sec.)
DELPOSN default value
Beginning of the ‘Delete Initial Position’ task
Figure 4 – DELPOSN timing diagram
Important Note: after the DELPOSN is activated, the receiver should make a position fix before it saves GPS data in its
back-up Flash memory.
If the DELPOSN is set “low” for more than 3 seconds, the BBFLASH content is erased and the receiver restarts in Cold
Start condition.
BTM – Board Test Mode selection
TDI, TDO, TMS, TCK – JTAG test interface
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RGPSM202
SlimGPS™ Receiver
5.2 OPERATING MODES
The receiver has 3 main operating modes, as summarized in the table below
Mode
Active Mode
Low Power Mode
Power Down Mode
Description
Receiver is running, doing acquisition,
tracking, position fixes
GPS receiver functions are turned OFF,
MCU clock is running
VCC pin
Powered
Current cons.
25 mA
GPS receiver functions are turned OFF,
MCU clock is stopped, RTC is running
on the Back-up supply
No power
Powered
through “LP”
NMEA
command
Low
2.2 mA
2 uA
Table 3 – Operating Modes
Active
“LP” NMEA
com
“LP” NMEA
com
Low Power
VCC switched Off
VCC switched On
Power down
Figure 5 - Switching between operating modes
Notes on TTFF / start-up condition:
• When switching from any state to Active mode, the start up condition will be
o Hot start if Almanac is valid, Ephemeris is valid (less than 4 hours old), approximate position is known
and RTC is valid
o Warm start if Almanac is valid, Ephemeris is not valid, approximate position is known and RTC is valid
o Cold start otherwise
5.2.1
Operating the GPS receiver in a basic “stand-alone” configuration
The simplest and easiest way to operate the RGPSM202 is the stand-alone configuration described below. In this case,
the GPS receiver is simply controlled by its main power supply. It only sends NMEA strings through its TXDA line. The
data interface should be connected as follows:
Pin
1, 2
3
4
5
6, 9, 17, 20, 21
Name
TDI, TCK,
TDO
TMS
RXDA
DGND
Connection
To VCC
N.C.
To VCC or N.C
To VCC or N.C
To digital ground
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RGPSM202
SlimGPS™ Receiver
Pin
7
Name
TXDA
8
10, 11, 12, 13, 15
14
16
18
19
22
23
24
VCC
RFGND
RF IN
DELPOSN
VBKP
PPS
POSFIX (BT1)
ALMRDY (BT0)
BTM
Connection
To the host interface, microcontroller, or other device that
read the NMEA strings
To main power supply
RF Ground
To active GPS antenna
To VCC or N.C.
RTC Battery back-up
N.C.
N.C.
N.C.
To VCC or N.C.
Table 4 - Basic data interface to operate the receiver in “stand-alone” configuration
Turning the main supply VCC on and off will switch the module into Active or Power-Down modes (see Figure 5 above).
When turned on, after the internal power-up sequence, the RGPSM202 will send the NMEA sentences through its
TXDA pin. In this configuration, the serial port settings, the type of NMEA sentences, and the output rate are those
defined in Flash in the Default Parameters Table (see Section 6 below). No other initialization is required.
5.2.2
Operating the GPS receiver in a basic “serial, bidirectional” configuration
This is a slightly more elaborate way to operate the RGPSM202. Compared to Paragraph 5.2.1, the module can receive
command/data ASCII character strings from its RXDA serial line. In this case the RXDA line should be connected to a
host, microcontroller, or any other device that can send NMEA strings through a UART.
Pin
Name
Connection
5
RXDA
To the host, microcontroller, or other device that send the NMEA strings
Other pins similar to Table 4 above
Table 5 - Basic data interface to operate the receiver in “serial, bidirectional” configuration
Turning the main supply VCC on and off will switch the module in Active or Power-Down modes (see Figure 5 above).
When turned on, after the internal power-up sequence, the RGPSM202 will send the NMEA sentences through its
TXDA pin. In this configuration, the serial port settings, the type of NMEA sentences, and the output rate are those
defined in Flash in the Default Parameters Table (see Section below). These parameters can then be temporarily
modified by 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.
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RGPSM202
SlimGPS™ Receiver
5.3 NMEA STANDARD MESSAGE SET SPECIFICATION
The RGPSM202 supports NMEA-0183 v3.0 output messages listed below. Brief descriptions of these messages are
provided below.
5.3.1
NMEA Standard Sentences
Semtech receivers use the standard output messages listed in Table 6:
NMEA
Message Description
GGA
Global positioning system fixed data
GLL
Geographic position – latitude/longitude
GSA
GNSS DOP and active satellites
GSV
GNSS satellites in view
RMC
Recommended minimum specific GNSS data
VTG
Course over ground and ground speed
ZDA
Time & Date
Table 6. NMEA-0183 Messages
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.
5.3.1.1 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 degrees 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 degree 6.129 minutes is represented by the string “04506.129”, “04506.1290”, or
“04506.12900”
5.3.2
GGA —Global Positioning System Fixed Data
Description: This message reports the global positioning system fixed data, as shown in Table 7.
Name
Example
Units
Description
Message ID
$GPGGA
GGA protocol header
UTC Position
161229.487
hhmmss.sss
Latitude
3723.2475
ddmm.mmmm
N/S Indicator
N
N = north or S = south
Longitude
12158.3416
dddmm.mmmm
E/W Indicator
W
E = east or W = west
Position Fix Indicator
1
See xxx0
Satellites Used
07
Range 0 to 12
HDOP
1.0
Horizontal Dilution of Precision
9.0
Meters
MSL Altitude1
Units
M
Meters
Meters
Geoid Separation1
Units
M
Meters
Age of Diff. Corr.
Second
Null fields when DGPS is not used
Diff. Ref. Station ID
0000
Checksum
*18
<CR><LF>
End of message termination
1
does not support geoid corrections. Values are WGS-84 ellipsoid heights.
Table 7. GGA Data Format
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RGPSM202
SlimGPS™ Receiver
Value
0
1
2
3
Description
Fix not available or invalid
GPS SPS Mode, fix valid
Differential GPS, SPS Mode, fix valid
GPS PPS Mode, fix valid
Table 8. Position Fix Indicator
Example: The values reported in this example are interpreted as shown in Table 7:
$GPGGA,161229.487,3723.2475,N,12158.3416,W,1,07,1.0,9.0,M, ,M, ,0000*18
5.3.3
GLL—Geographic Position - Latitude/Longitude
Description: This message reports latitude and longitude geographic positioning data, as described in Table 9.
Name
Message ID
Latitude
N/S Indicator
Longitude
E/W Indicator
UTC Position
Status
Mode Indicator
Example
$GPGLL
3723.2475
N
12158.3416
W
161229.487
A
A
Checksum
<CR><LF>
*2C
Description
GLL protocol header
dd mm.mmmm
N = north or S = south
ddd mm.mmmm
E = east or W = west
hh mm ss.sss
A = data valid or V = data not valid
A = autonomous, D = differential, E = estimated,
M = manual input, S=simulator mode, N = not valid
End of message termination
Table 9. GLL Data Format
Example: The values reported in this example are interpreted as shown in Table 9:
$GPGLL,3723.2475,N,12158.3416,W,161229.487,A,A*2C
5.3.4
GSA—GNSS DOP and Active Satellites
Description: This message reports the satellites used in the navigation solution reported by the GGA message. GSA is
described in Table 10.
Name
Example
Description
Message ID
$GPGSA
GSA protocol header
Mode 1
A
See Table 11
Mode 2
3
See Table 12
07
SV on Channel 1
Satellite Used 1
02
SV on Channel 2
Satellite Used 1
…
…
SV on Channel N
Satellite Used 1
PDOP
1.8
Position Dilution of Precision
HDOP
1.0
Horizontal Dilution of Precision
VDOP
1.5
Vertical Dilution of Precision
Checksum
*33
<CR><LF>
End of message termination
1
Satellite used in solution.
Table 10. GSA Data Format
Value
M
A
Description
Manual – forced to operate in 2D or 3D mode
Automatic – allowed to automatically switch 2D/3D
Table 11. Mode 1
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RGPSM202
SlimGPS™ Receiver
Value
1
2
3
Description
Fix not available
2D
3D
Table 12. Mode 2
Example: The values reported in this example are interpreted as shown in Table 10:
$GPGSA,A,3,07,02,26,27,09,04,15, , , , , ,1.8,1.0,1.5*33
5.3.5
GSV—GNSS Satellites in View
Description: This message reports the satellites in view, their ID numbers, elevation, azimuth, and SNR values (up to
four satellites per message). GSV is described in Table 13.
Name
Message ID
Number of Messages1
Message Number 1
Satellites in View
Satellite ID
Elevation
Example
$GPGSV
2
1
07
07
79
Units
Description
GSV protocol header
Range 1 to 3
Range 1 to 3
degrees
Channel 1 (Range 1 to 32)
Channel 1 (Maximum 90)
Azimuth
048
degrees
Channel 1 (True, Range 0 to 359)
SNR (C/No)
42
dBHz
Range 0 to 99, null when not tracking
…
…
Satellite ID
27
Channel 4 (Range 1 to 32)
Elevation
27
degrees
Channel 4 (Maximum 90)
Azimuth
138
degrees
Channel 4 (True, Range 0 to 359)
SNR (C/No)
42
dBHz
Range 0 to 99, null when not tracking
Checksum
*71
<CR><LF>
End of message termination
1
Depending on the number of satellites tracked multiple messages of GSV data may be required.
Table 13. GGA Data Format
Example: The values reported in this example are interpreted as shown in Table 13. Two messages are required to
complete the data transmission.
$GPGSV,2,1,07,07,79,048,42,02,51,062,43,26,36,256,42,27,27,138,42*71
$GPGSV,2,2,07,09,23,313,42,04,19,159,41,15,12,041,42*41
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RGPSM202
SlimGPS™ Receiver
5.3.6
RMC—Recommended Minimum Specific GNSS Data
Description: This message reports the time, date, position, course, and speed from the receiver’s navigation solution.
RMC is described in Table 14.
Name
Message ID
UTC Position
Example
$GPRMC
161229.487
Status
A
A = data valid or V = data not valid
Latitude
N/S Indicator
Longitude
E/W Indicator
Speed Over Ground
Course Over Ground
Date
Magnetic Variation1
E/W Indicator
Mode Indicator
3723.2475
N
12158.3416
W
0.13
309.62
120598
02.6
W
A
Dd mm.mmmm
N = north or S = south
Ddd mm.mmmm
E = east or W = west
Checksum
<CR><LF>
*10
1
Units
Description
RMC protocol header
Hh mm ss.sss
knots
degrees
True
Dd mm yy
degrees
E = east or W = west
A = autonomous, D = differential, E = estimated,
M = manual input, S=simulator mode, N = not valid
End of message termination
All "course over ground" data are geodetic WGS84 directions.
Table 14. RMC Data Format
Example: The values reported in this example are interpreted as shown in Table 14:
$GPRMC,161229.487,A,3723.2475,N,12158.3416,W,0.13,309.62,120598, 02.6,W,A*10
5.3.7
VTG—Course Over Ground and Ground Speed
Description: This message reports current ground course and speed data. Course is reported relative to true north only.
The VTG message is defined in Table 15.
Name
Message ID
Course
Reference
Course
Reference
Speed
Units
Speed
Units
Mode Indicator
Example
$GPVTG
309.62
T
139.6
M
0.13
N
0.2
K
A
Units
degrees
degrees
knots
km/hr
Checksum
*6E
<CR><LF>
1
All "course over ground" data are geodetic WGS84.
Description
VTG protocol header
Measured heading
True
Measured heading
Magnetic 1
Measured horizontal speed
Knots
Measured horizontal speed
Kilometer per hour
A = autonomous, D = differential, E = estimated,
M = manual input, S=simulator mode, N = not valid
End of message termination
Table 15. VTG Data Format
Example: The values reported in this example are interpreted as shown in Table 15:
$GPVTG,137.7,T,139.6,M,007.4,N,013.7,K,A*47
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5.3.8
ZDA—Time & Date
Description: This message reports current time and date. The ZDA message is defined in Table 16.
Name
Message ID
Hour, Min, Sec, Sub Sec
Day
Month
Year
Local Zone Hours
Local Zone Minutes
<CR><LF>
Example
$GPZDA
114523.62
12
04
2001
10
34
Units
Description
ZDA protocol header
hhmmss.ss
day in UTC, 01 to 31
month in UTC, 01 to 12
year in UTC
local zone hours, +/- 13 hours
local zone minutes, 0 to +59
End of message termination
Table 16 ZDA Data Format
Example: The values reported in this example are interpreted as shown in Table 15:
$GPZDA,114523.62,12,04,2001,10,34*6E
5.3.9
GPQ—NMEA Sentence Query
Description: Query of a specific NMEA sentence. Any GGA, GLL, GSA, GSV, RMC, VTG, or ZDA sentence can be
queried manually by sending this query sentence to the receiver. The requested sentence will be sent only once. The
GPQ message is defined in Table 17.
Name
Message ID
NMEA id
Example
$GPGPQ
RMC
Units
<CR><LF>
Description
GPQ protocol header
Identifier of the requested NMEA sentence: GGA,
GLL, GSA, GSV, RMC, VTG, or ZDA
End of message termination
Table 17 GPQ Data format
Example: $GPGPQ,RMC*21
$GPRMC,161229.487,A,3723.2475,N,12158.3416,W,0.13,309.62,120598, 02.6,W,A*10
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5.4 NMEA SPECIFIC SENTENCES
The NMEA 0183 Standard dictates that proprietary NMEA sentences have the following structure:
$Paaaxxxxxxxxxxxxx*hh
where aaa – mnemonic code, XEM in our case; xxxxxxxxx…– data; hh – sentence checksum
Two types of input sentences are defined: query and set. Query sentences request certain information from the
receiver. Set sentences allow configuring the receiver with certain configuration parameters or forcing the receiver to
perform a specific action. For each type of input sentences, a corresponding output response sentence is defined.
For a query sentence, the response sentence contains requested data. For a set sentence, the response sentence
contains the status of the action requested in the set sentence. Taking these aspects into account, the following is the
general structure of the specific NMEA sentence:
$PXEMmaa,x1,x2,x3,x4,….,xN*hh
where m – sentence type: ‘Q’ for ‘query’, ‘S’ for ‘set’, ‘R’ for ‘response’; aa – proprietary sentence identifier (see below);
x1…xN – data parameters (only for set and query response sentences); hh – sentence checksum
NOTE: Each of the data parameters must be preceded with a comma, except for the aa sentence identifier, and the
checksum which is preceded with a checksum delimiter character ‘*’.
• QUERY sentence: to send a query sentence, no data fields are transmitted. The following format is used:
$PXEMQaa*hh
• RESPONSE sentence to QUERY: for a query sentence, a response sentence with all fields is transmitted. The
following format is used:
$PXEMRaa,x1,x2,x3,x4,….,xN*hh
• SET sentence: to send a set sentence, x1…xN must contain valid values. The following format is used:
$PXEMSaa,x1,x2,x3,x4,….,xN*hh
• RESPONSE sentence to SET: for a set sentence, a status response sentence is transmitted. The following format is
used:
$PXEMRaa,s*hh
where s is the status of the requested action: ‘A’ if the action was successful; ‘V’ otherwise.
The following proprietary NMEA sentence identifiers are implemented:
5.4.1
DI – Diagnostic Message
This sentence outputs a diagnostic string. It is used to report various error conditions. This is a response-only sentence.
$PXEMRDI,ccccccc*hh
where ccccccc is a diagnostic string up to 50 characters
5.4.2
TF—Quick Test
Description: This sentence contains information which helps a monitoring station figure out the status of the receiver.
This sentence can be automatically output at a given rate by setting Bit #9 of the NMEA sentence mask (see NMSentence Mask and Automatic Output Rate section below). This is a query-only sentence.
$PXEMaTF,a,a,xxxxxx,xx,x,llll.lllll,a,yyyyy.yyyyy,a,xxxxx*hh
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Name
Message ID
BBFStatus
Example
$PXEMaTF
A
AlmStatus
A
GPSTime
SatInView
FixSource
Lat
N/S
Lon
E/W
Alt
12367
06
3
34.1453
N
Units
seconds
deg
deg
E
283
meter
<CR><LF>
Description
TF protocol header, (a: Q = query; R = response)
a: BBFlash status on startup (A = valid; V =
invalid)
a: Almanac completion status (A = complete; V =
incomplete)
xxxxxx: GPS time of week
xx: Number of satellites in use
x: Position fix source (0=no fix; 2=2D fix; 3=3D fix)
llll.lllll: Latitude of the current position fix
a: N (North), S (South)
yyyyy.yyyyy: Longitude of the current position fix
a: E (East), W (West)
xxxxx: Antenna altitude ref mean-sea-level (MSL
geoid)
End of message termination
Table 18 TF Data Format
Example:
$PXEMQTF*6E
$PXEMRTF,A,A,112345,05,2,45.45677,N,6.26789,E,387*6E
5.4.3
NM – Sentence Mask and Automatic Output Rate
This sentence configures the application to automatically output standard NMEA sentences at a specified time interval.
$PXEMaNM,xxxx,xx*hh
Name
Message ID
Example
$PXEMaNM
Mask
0008
Rate
<CR><LF>
01
Units
sec
Description
Proprietary NM protocol header, a-mode (Q =
query; S = set; R = response)
xxxx Output sentence mask, hex value (see Notes
below)
xx Automatic output sentence rate (00 to 99)
End of message termination
Table 19 NM Data Format
Notes: xxxx is a hexadecimal value representing a 2-byte bit-mask where a specific bit sets or clears automatic output
of a particular NMEA sentence according to the table below. The mask is derived by combining all bits which represent
the NMEA sentences which will be automatically output. For example, to automatically output GGA, GSA, ZDA, and
RMC, the bits 0, 4, 5, and 8 are set to 1 in a 2-byte mask, resulting in a hex value 0x131 (0x1+0x10+0x20+0x100). This
value is sent as an ASCII string ‘0131’ in the xxxx field of the NM sentence.
Sentence
Bit#
Field value
GLL
1
0002
GGA
0
0001
GLL
1
0002
VTG
2
0004
GSV
3
0008
GSA
4
0010
ZDA
5
0020
RMC
8
0100
TF
9
0200
Table 20 Possible MASK field values for the NM command
Example: $PXEMSNM,0008,01*6E
(set)
$PXEMRNM,a*6E
(response to set: a – action status: A = success; V = failure)
Example: $PXEMQNM*6E
$PXEMRNM,0119,01*6E
(query)
(response to query)
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5.4.4
PS – Pulse-Per-Second Configuration
This sentence sets the pulse-per-second (PPS) output on or off. This is a set-only sentence.
$PXEMaPS,x*hh
Name
Message ID
Example
$PXEMaPS
On/Off
<CR><LF>
1
Units
Description
Proprietary PS protocol header, a-mode (S = set;
R = response0
PPS output switch (1 = ON; 0 = OFF)
End of message termination
Table 21 PS Data Format
Example:
$PXEMSPS,1*6E
$PXEMRPS,a*6E
(set)
(response to set: a – action status: A = success; V = failure)
5.4.5
PT – Port Configuration
This sentence configures the application serial port communication parameters.
$PXEMaPT,xxxxxx,x,a,x*hh
Name
Message ID
Example
$PXEMaPT
Baudrate
009600
Data length
Parity
Stop bit
<CR><LF>
8
N
1
Units
Description
Proprietary PT protocol header, a-mode (S = set;
R = response)
xxxxxx Baud rate (057600, 038400, 019200,
009600, 004800, 002400)
x # of data bits (7 or 8)
Parity (N = None; O = Odd; E = Even)
# of stop bits (1 or 2)
End of message termination
Table 22 PT Data Format
Example:
$PXEMSPT,009600,8,N,1*6E
(set)
$PXEMRPT,a*6E
(response to set: a – action status: A = success; V = failure)
5.4.6
RT – Reset the Receiver / Start-Stop FirstGPS
This sentence forces the receiver to perform a software reset. It also allows starting up and shutting down the FirstGPS
library without performing a full software reset. This is a set-only sentence.
$PXEMaRT,a*hh
Name
Message ID
Example
$PXEMaRT
Command
S
Units
<CR><LF>
Description
Proprietary RT protocol header, a-mode (S = set;
R = response)
C = cold software reset
W = warm software reset
H = hot software reset
S = start the FirstGPS library
X = shut down the FirstGPS library
B = save GPS data into the BBFLASH (ignored if
there is no position fix)
End of message termination
Table 23 RT Data Format
Example:
$PXEMSRT,W*6E
$PXEMRRT,a*6E
(set)
(response to set: a – action status: A = success; V = failure)
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5.4.7
VR – Version Information
This sentence obtains software versions for the measurement platform (MPM) firmware, FirstGPS API, FirstGPS
Library, native RTOS, and native processor (CPU). This is a query-only sentence.
Note: A complete VR sentence returns only the version of a particular product component one at a time (either MPM
firmware, API, library, RTOS or CPU). The sentence must include the component type for which to obtain the version
for any given query.
$PXEMaVR,a,cccccc,xx,xx,xx,xx,xx,xxxx*hh
Name
Message ID
Example
$PXEMaVR
Component type
A
Name
abcdef
Maj version
Min version
Beta version
Month
Day
Year
<CR><LF>
04
02
03
10
27
2002
Units
Description
Proprietary RT protocol header, a-mode (Q =
query; R = response)
M = measurement platform (MPM) firmware
A = FirstGPS API
N = FirstGPS Library
R = native RTOS
U = native processor (CPU)
V = Software build
variable length field; may be up to 17 characters
long
Major version number (00 to 99)
Minor version number (00 to 99)
Beta version number (00 to 99)
Month of the release (01 to 12)
Day of the release (01 to 31)
Year of the release
End of message termination
Table 24 VR Data Format
Example:
$PXEMQVR,R*6E
(query)
$PXEMRVR,R,nucleus,04,03,03,10,27,2000*6E
(response to query)
5.4.8
GS – Geodetic System Configuration
This sentence sets the geodetic system use to compute the geographic positioning data.
$PXEMaGS,ee,xxxx.xxxxxx,yyyy.yyyyyy,zzzz.zzzzzz*hh
Name
Message ID
Example
$PXEMaGS
Ellipsoid
Delta X
Delta Y
Delta Z
<CR><LF>
12
-0.148
0.096
0.122
Units
m
m
m
Description
Proprietary GS protocol header, a-mode (S = set;
R = response)
ee Ellipsoid Model (see table below)
xxxx.xxxxxx, shift parameter on x axis
yyyy.yyyyyy, shift parameter on y axis
zzzz.zzzzzz, shift parameter on z axis
End of message termination
Table 25 GS Data Format
Index
00
01
02
03
04
05
Ellipsoid Name
Airy 1830
Australian National & South American 1969
Bessel 1841 Ethiopia
Bessel 1841 Namibia
Clarke 1866
Clarke 1880
© Semtech 2005
Semi-Major Axis
6377563.396
6378160
6377397.155
6377483.865
6378206.4
6378249.145
Flattening
299.3249646
298.25
299.1528128
299.1528128
294.9786982
293.465
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06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
Everest Brunei and E. Malaysia
Everest India 1830
Everest India 1956
Everest Pakistan
Everest W. Malaysia and Singapore 1948
Geodetic Reference System 1980
Helmert 1906
Hough 1960
Indonesian 1974
International 1924 & Hayford
Krassovsky 1940
Modified Airy
Modified Fischer 1960
WGS 1972
WGS 1984
6377298.556
6377276.345
6377301.243
6377309.613
6377304.063
6378137
6378200
6378270
6378160
6378388
6378245
6377340.189
6378155
6378135
6378137
300.8017
300.8017
300.8017
300.8017
300.8017
298.257222101
298.3
297
298.247
297
298.3
299.3249646
298.3
298.26
298.257223563
Table 26 Ellipsoid models
Example:
$PXEMSGS,12,-0.148,0.096,0.122*44 (set)
$PXEMRGS,a,12,-0.148,0.096,0.122*08 (response to set: a – action status: A = success; V
= failure)
see also Exhibit A for further examples
5.4.9
LP – Power Save Mode
This sentence sets the receiver in Power Save mode. To go back to the Active mode, users should send any valid
NMEA sentence to the receiver. Do not toggle the ON/OFF pin to go to the Active Mode if a NMEA LP command is
used to switch to the Power Save mode
$PXEMaLP*hh
Name
Message ID
Example
$PXEMaLP
Units
<CR><LF>
Description
Proprietary LP protocol header, a-mode (S = set;
R = response)
End of message termination
Table 27 LP Data format
Example:
$PXEMSLP*4F (set)
$PXEMRLP,a*23
(response to set: a – action status: A = success; V = failure)
5.4.10
TR – Transparent Mode
With this type of sentence, an API function call is passed thru the NMEA interface. This can be a query, set, and
response type of sentence.
$PXEMaTR,c..c,x..xx, .., x..x*hh
Example:
$PXEMQTR,SQCS*6E
$PXEMRTR,SQCS,NAV_OK,GPS Time of Week,Channel status for satellite 1, … Channel
status for satellite n*4F
(response to the channel status query)
The most useful TR types of proprietary NMEA sentences are listed below. See Exhibit B for detailed information on all
the API function calls
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RGPSM202
SlimGPS™ Receiver
5.4.10.1 Set the RTC time
The purpose of GPS time is to allow use of the almanac data and position to determine which satellites are in view and
to allow rough ranging to the satellites. XE1610-PVT products load GPS time every start-up. If the local RTC, from
which this GPS time is loaded, is not valid it is possible to provide the GPS time from another source. The accuracy of
this external source should be better than 30 minutes.
The time/date information in the GPS system is coded using a standard GPS time format that is a week number and the
time of the week. The week number of the GPS time is the number of weeks from Sunday, January 6 1980. However,
due to the GPS data message format, the week number is a modulo-1024 number (10-bit number). The last rollover
occurred on August 22, 1999. The next rollover will happen on April 7, 2019. The GPS time of the week is the number
of milliseconds since the beginning of the current GPS week, the GPS week starting on Sundays at 0 hour, 0 minute, 0
millisecond.
When the GPS engine is running the TR sentence to use is:
$PXEMSTR,SSIT,WeekNb,TimeOfWeek,Accu*hh
where:
• WeekNb is the week number (see above)
• TimeOfWeek is the time of the week information, in milliseconds (see above)
• Accu (integer value) reflects the accuracy of the time information provided to the system. Use 1 only if the time of
the week and the week number are valid (accuracy better than 30 minutes), otherwise -1
Important notes:
- if the Accu parameter is set to 1, the hardware RTC will be updated when receiving this command
- if the Accu parameter is set to -1, the hardware RTC will NOT be updated when receiving the sentence
- if the Accu parameter is set to another negative value, the hardware RTC will be updated when receiving the
sentence.
Also, it is strongly advised to avoid setting the Accu parameter to 1 if one is not sure about the accuracy, as this may
lead to improper behavior.
5.4.10.2 Set the initial position
The purpose of the rough initial position is to allow use of the almanac data and GPS time to determine which satellites
are in view. This is achieved by sending a proprietary TR command which format is:
$PXEMSTR,SSIP,L.LLL,O.OOO,Alt,Accu*hh
where:
• L.LLL is the latitude expressed in radian
• O.OOO is the longitude expressed in radian
• Alt is the altitude expressed in meter. Note that if you are not sure about the altitude, a default value of 200 gives
acceptable results in most cases.
• Accu reflects the accuracy of the initial position. Use -1
For example, to set the position to New Delhi in India (coordinates being lat: 0.499, lon: 1.347), the full sentence should
be:
$PXEMSTR,SSIP,0.499,1.347,200,-1*hh
The initial position can only be set when the GPS engine is running and before the system does position fix. Note that
an initial position error of 1,000 km will result in an almanac based satellite search set which has rotated out of view by
approximately 10%. Beyond this, the specified performance will degrade. Initial position errors greater than 3,000 km
will result in a constellation which is almost out of view. So, the recommendation is to set the initial position only if its
accuracy is better than 1,200 km.
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Important Note: after the receiver gets this command the content of the GPS data RAM will be saved in the back-up
Flash upon the first position fix.
5.4.10.3 Delete the initial position
This NMEA sentence has the same effect as the hardware input DELPOSN. It allows deleting the initial position in the
RAM portion of the MCU and triggering re-computation of the tracking set. The position will not be deleted if GPS fixes
are already being generated. This function is useful when the initial position is known to be incorrect, for example when
the receiver is powered down, put on a plane, flown 20,000 km, and then warm-started. The command is:
$PXEMSTR,SSDI*74
Important Note: after the PXEMSTR,SSDI command is sent, the receiver should make a position fix before it saves
GPS data in its back-up Flash memory.
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RGPSM202
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5.5 GPS DATA BACK-UP
The almanac data is the information transmitted by each satellite on the orbits and state (health) of the entire
constellation. The ephemeris is a list of accurate positions or locations of celestial objects as a function of time. So, the
availability of almanac and ephemeris data, in addition to time and approximate position, allows the GPS receiver to
rapidly acquire satellites as soon as it is turned on. There are 3 possible start conditions when the receiver is turned on:
a) the Cold Start, that is the start-up sequence of the receiver when no initialization data is available; b) the Warm Start,
that is the start-up sequence of the receiver when the last position, the time and the almanac information are available;
and c) the Hot Start, that is the start-up sequence of the receiver when the ephemeris, the last position, the time and the
almanac information are available.
In the RGPSM202, the GPS data structure, including almanac, ephemeris and last position fix, is copied into a specific
sector of the on-board Flash memory, that’s the back-up Flash sector, or BBFlash. The data are stored the first time the
almanac is complete and up-to-date, then every M minutes, where M is defined in Default Parameters Table *,
parameter #37. Alternatively, the Flash can be programmed with valid information during the manufacturing process.
This is to avoid downloading it from satellites, which takes approx. 12.5 minutes. Then, as long as the main power
supply remains turned ON, the GPS data structure is kept in RAM. However, data in RAM are not maintained if the main
supply is switched OFF (or in case of a power failure). In this case, upon power up, these data are uploaded from the
Flash back-up memory into the GPS data RAM. Provided these data are valid – 2 months for the Almanac, 2 hours for
ephemeris – the TTFF will be shorter than Cold Start TTFF, since the receiver will be in Warm or Hot start condition.
(*) see the Default Settings section below
With the Flash technology embedded in the design, it takes approx. 0.5 seconds typ., 1 second max. to erase and
update the Flash sectors where the GPS data structure is stored.
5.6 REAL TIME CLOCK
The receiver board has a hardware Real Time Clock chip that operates independently from the MCU and the GPS
function. When the GPS receiver is active and as soon as the GPS time becomes available the RTC is synchronized
with GPS time. Then, as long as GPS time is available, the RTC is synchronized every 60 seconds.
If the main power supply VCC is turned OFF and provided the VRTCBK supply is available, the RTC operates and keep
RTC information up to date. By doing so, when both the main VCC supply and the GPS receiver are turned ON again
the time information will be available.
5.7 SPLIT SEARCH MODE
This feature is useful when the initial position is incorrect, for example when the receiver is powered down, put on a
plane, flown 10,000 km, and then warm-started. If the user does not activate the DELPOSN I/O or does not send the
proprietary PXEMSTR,SSDI NMEA command, the receiver will start to search for the satellites it believes are above it
(warm start condition). However, after approximately 5 minutes, it will free up some of its channels to search for other
satellites in the constellation. When it finds one it will free up more channels and recover from a Warm start with an
inaccurate initial position.
5.8 HARDWARE RESET AND SYSTEM WATCHDOG
The receiver has an embedded microcontroller voltage supply supervisor. This device will automatically generate a
hardware reset if the voltage supply goes under the specified value. In this case, the receiver will restart from a known
and stable state in case of a power shortage on the main supply while in operation.
In addition, the receiver firmware includes a system watchdog reset procedure. Should a system exception occur, the
receiver will execute a software reset to restart operation in a safe mode. In this case the receiver will not have position
fixes for 15 seconds on average.
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6
DEFAULT SETTINGS
A number of system settings are stored in a particular area of the embedded Flash. These are the default parameters
whose contents are given in the table below. Some of these settings can be modified by sending a proprietary NMEA
sentence to the receiver, as defined above.
#
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
Default parameter
PPS Output Enabled
NMEA refresh rate
NMEA GGA output displ’d
NMEA GLL output displ’d
NMEA VTG output displ’d
NMEA GSV output displ’d
NMEA GSA output displ’d
NMEA ZDA output displ’d
NMEA RMC output displ’d
NMEA TF output displ’d
NMEA GGA display order
NMEA GLL display order
NMEA VTG display order
NMEA GSV display order
NMEA GSA display order
NMEA ZDA display order
NMEA RMC display order
NMEA TF display order
Serial Port A Baudrate
Serial Port A Data bits
Serial Port A Stop bits
Serial Port A Parity bits
Serial Port B Baudrate
Serial Port B Data bits
Serial Port B Stop bits
Serial Port B Parity bits
Data Type
Char
Integer
Char
Char
Char
Char
Char
Char
Char
Char
Integer
Integer
Integer
Integer
Integer
Integer
Integer
Integer
Integer
Integer
Integer
Character
Integer
Integer
Integer
Character
Default value
Y
1 second
Y
N
N
Y
Y
N
Y
N
2
5
6
4
1
7
3
8
9600
8
1
N
9600
8
1
N
Range values
Y/N
1 to 99 seconds
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
Y/N
1 .. 8
1 .. 8
1 .. 8
1 .. 8
1 .. 8
1 .. 8
1 .. 8
1 .. 8
2400 / 4800 / 9600 / 19200 / 38400 / 57600
7 .. 8
1 .. 2
N/O/E
2400 / 4800 / 9600 / 19200 / 38400 / 57600
7 .. 8
1 .. 2
N/O/E
27 Dynamic Code
Integer
5
1 – Land
2 – Sea
3 – Air
4 – Stationary
5 - Automobile
28
29
30
31
32
33
34
35
36
Real
Real
Real
Real
Real
Integer
Real
Real
Real
7.9e-6
0.087
1.3
16
8
20
0
0
0
Depends on the Oscillator
0 to Pi/2 radian
1 to 20
0.2 to 40
0.2 to 40
0 to 20
-9999.99999 to +9999.99999
-9999.99999 to +9999.99999
-9999.99999 to +9999.99999
32 bits Integer
10
1 to (2**32)-1
Max Oscillator Offset
Elevation Mask (radian)
Signal Level Mask (AMU)
DOP Mask
PDOP Switch
Geodetic System Ellipsoid
Geodetic System Delta X
Geodetic System Delta Y
Geodetic System Delta Z
BBFLASH Update rate
37
(minutes)
Table 28 – Default Parameters
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RGPSM202
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6.1 GPS ENGINE CONFIGURATION
In addition, there are some settings for the embedded FirstGPS navigation software that cannot be modified by the
users
6.1.1
Receiver configuration
DGPS Mode
DGPS Off
6.1.2
Filter configuration
Kalman Filter
6.1.3
Offset configuration
Offset
0 ppm
Window
-1 ppm
6.1.4
Application settings
Number of channels
Week epoch
7
8
1024
the offset number of 1024 week periods since 6 January
1980. Setting to 1024 includes all dates between August
22, 1999 and March 2019.
APPLICATION INFORMATION
7.1 ACTIVE ANTENNA
For proper operation, the RGPSM202 receiver should be operated with an active GPS antenna that has the following
characteristics
Power supply voltage
3 - 3.6 V
1,575.42+/-1.023 MHz
Frequency range
LNA Gain
26 dB typ. at 3.0V
LNA NF
1.3 dB typ. at 3.0V
Antenna and LNA total Gain
25 dBi Max at 3.0V
© Semtech 2005
www.semtech.com
24
RGPSM202
SlimGPS™ Receiver
8
EXHIBIT A
The following table illustrates datums for some cities around the world.
Country
City
NNEA Syntax
Wales
Cardiff
$PXEMSGS,00,375,-111,431*78
Australia
Sydney
$PXEMSGS,01,-134,-48,149*40
Japan
Tokyo
$PXEMSGS,02,-148,507,685*5C
Namibia
Windhoek
$PXEMSGS,03,616,-97,251*60
Cuba
Havana
$PXEMSGS,04,-3,142,183*50
Senegal
Dakar
$PXEMSGS,05,-128,-18,224*44
Brunei
Bandar S. B.
$PXEMSGS,06,-679,669,-48*4C
Thailand
Bangkok
$PXEMSGS,07,210,814,289*7D
India
Calcutta
$PXEMSGS,08,295,736,257*73
Pakistan
Karachi
$PXEMSGS,09,283,682,231*7B
Singapore
Singapore
$PXEMSGS,10,-11,851,5*62
Russia
Moscow
$PXEMSGS,11,1.08,0.27,0.9*6C
Egypt
Cairo
$PXEMSGS,12,-130,110,-13*44
Marshall Island
Majuro
$PXEMSGS,13,102,52,-38*57
Indonesia
Djakarta
$PXEMSGS,14,-24,-15,5*75
France
Paris
$PXEMSGS,15,-87,-96,-120*5D
© Semtech 2005
WGS-84 Datum
51° 23’ N
3° 20’ W
100.0 m
33° 52' S
151° 12' E
100.0 m
35° 41' N
139° 46' E
100.0 m
22° 34' S
17° 5' E
100.0 m
23° 08' N
82° 21' W
100.0 m
14° 42' N
17° 29' W
100.0 m
4° 56’ N
114° 50’ E
100.0 m
13° 44' N
100° 30' E
100.0 m
22° 32' N
88° 20' E
100.0 m
24° 48' N
66° 59' E
100.0 m
1° 18' N
103° 50' E
100.0 m
55° 46' N
37° 40' E
100.0 m
29° 52' N
31° 20' E
100.0 m
41° 32’ N
12° 18’ E
100.0 m
6° 11' S
106° 50' E
100.0 m
48° 49' N
2° 29' E
100.0 m
Local Datum
51° 22’ 58.454” N
3° 19’ 55.396” W
51.497 m
33° 52’ 5.738” S
151° 11’ 55.851” E
81.918 m
35° 40’ 48.239” N
139° 46’ 11.591” E
59.959 m
22° 33’ 58.644” S
17° 5’ 3.088” E
77.040 m
23° 7’ 58.302” N
82° 21’ 0.559” W
125.109 m
14° 41’ 57.554” N
17° 28’ 58.140” W
66.314 m
4° 56’ 3.033” N
114° 49’ 49.116” E
52.227 m
13° 43’ 54.002” N
100° 30’ 11.811” E
141.421 m
22° 31’ 57.337” N
88° 20’ 9.571” E
122.930 m
24° 47’ 58.714” N
66° 58’ 59.779” E
128.006 m
1° 18’ 0.179” N
103° 50’ 6.237” E
103.999 m
55° 46’ 0.010” N
37° 39’ 59.865” E
99.446 m
29° 51’ 59.415” N
31° 19’ 53.980” E
89.458 m
41° 32’ 6.227” N
12° 17’ 58.745” E
-50.775 m
6° 11’ 0.141” S
106° 49’ 59.111” E
84.912 m
48° 49’ 3.271” N
2° 29’ 4.516” E
50.964 m
www.semtech.com
25
RGPSM202
SlimGPS™ Receiver
Country
City
NNEA Syntax
Somalia
Mogadiscio
$PXEMSGS,16,-43,-163,45*72
Ireland
Dublin
$PXEMSGS,17,506,-122,611*58
Singapore
Singapore
$PXEMSGS,18,7,-10,26*51
Ireland
Dublin
$PXEMSGS,19,0,0,4.5*60
Ireland
Dublin
$PXEMSGS,20,0,0,0*75
© Semtech 2005
WGS-84 Datum
2° 2' N
49° 19' E
100.0 m
53° 22' N
6° 21' W
100.0 m
1° 18' N
103° 50' E
100.0 m
53° 22' N
6° 21' W
100.0 m
53° 22' N
6° 21' W
100.0 m
Local Datum
2° 1’ 58.354” N
49° 19’ 2.383” E
141.943 m
53° 21’ 59.163” N
6° 20’ 56.468” W
47.599 m
1° 18’ 0.833” N
103° 50’ 0.142” E
93.969 m
53° 21’ 59.906” N
6° 21’ 0.554” W
96.856 m
53° 22' N
6° 21' W
100.0 m
www.semtech.com
26
RGPSM202
SlimGPS™ Receiver
EXHIBIT B
The list and description of parameters for the $PXEMaTR proprietary NMEA sentence is a restricted document. It is
passed to customers on request and upon approval by Semtech.
© Semtech 2005
All rights reserved. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The
information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and
may be changed without notice. No liability will be accepted by the publisher for any consequence of its use. Publication thereof
does not convey nor imply any license under patent or other industrial or intellectual property rights. Semtech. assumes no
responsibility or liability whatsoever for any failure or unexpected operation resulting from misuse, neglect improper installation,
repair or improper handling or unusual physical or electrical stress including, but not limited to, exposure to parameters beyond the
specified maximum ratings or operation outside the specified range.
SEMTECH PRODUCTS ARE NOT DESIGNED, INTENDED, AUTHORIZED OR WARRANTED TO BE SUITABLE FOR USE IN
LIFE-SUPPORT APPLICATIONS, DEVICES OR SYSTEMS OR OTHER CRITICAL APPLICATIONS. INCLUSION OF SEMTECH
PRODUCTS IN SUCH APPLICATIONS IS UNDERSTOOD TO BE UNDERTAKEN SOLELY AT THE CUSTOMER’S OWN RISK.
Should a customer purchase or use Semtech products for any such unauthorized application, the customer shall indemnify and
hold Semtech and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs damages and
attorney fees which could arise.
Contact Information
Semtech Corporation
Wireless and Sensing Products Division
200 Flynn Road, Camarillo, CA 93012
Phone (805) 498-2111 Fax : (805) 498-3804
© Semtech 2005
www.semtech.com
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