Sunsea AIoT SIMCom SIM66 Series User manual

SIM66 Series_NMEA
Message_User Guide
SIMCom Wireless Solutions Limited
SIMCom Headquarters Building, Building 3, No. 289 Linhong
Road, Changning District, Shanghai P.R. China
Tel: [phone]
[e-mail]
www.simcom.com
GNSS Module

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Document Title:
SIM66 Series_NMEA Message_User Guide
Version:
1.01
Date:
2021.11.04
Status:
Released
GENERAL NOTES
SIMCOM OFFERS THIS INFORMATION AS A SERVICE TO ITS CUSTOMERS, TO SUPPORT
APPLICATION AND ENGINEERING EFFORTS THAT USE THE PRODUCTS DESIGNED BY SIMCOM.
THE INFORMATION PROVIDED IS BASED UPON REQUIREMENTS SPECIFICALLY PROVIDED TO
SIMCOM BY THE CUSTOMERS. SIMCOM HAS NOT UNDERTAKEN ANY INDEPENDENT SEARCH
FOR ADDITIONAL RELEVANT INFORMATION, INCLUDING ANY INFORMATION THAT MAY BE IN THE
CUSTOMER’S POSSESSION. FURTHERMORE, SYSTEM VALIDATION OF THIS PRODUCT
DESIGNED BY SIMCOM WITHIN A LARGER ELECTRONIC SYSTEM REMAINS THE RESPONSIBILITY
OF THE CUSTOMER OR THE CUSTOMER’S SYSTEM INTEGRATOR. ALL SPECIFICATIONS
SUPPLIED HEREIN ARE SUBJECT TO CHANGE.
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CHANGE WITHOUT NOTICE AT ANY TIME.
SIMCom Wireless Solutions Limited
SIMCom Headquarters Building, Building 3, No. 289 Linhong Road, Changning District, Shanghai P.R.
China
Tel: [phone]
Email: [email protected]
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About Document
Version History
Version
Date
Owner
What is new
V1.00 2021.01.19 Jian.ni Original
V1.01 2021.11.04 Wenjie.lai Add SIM66M in scope
Scope
This document applies to the following products
Name
Type
Size(mm)
Comments
SIM66MB GPS+BDS 9.7*10.1*2.5 N/A
SIM66M GPS+GLONASS 9.7*10.1*2.5 N/A

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Contents
About Document....................................................................................................................3
Version History ......................................................................................................................................3
Scope ....................................................................................................................................................3
Contents .................................................................................................................................4
1Introduction......................................................................................................................5
1.1 Purpose of the document ........................................................................................................5
1.2 Related documents .................................................................................................................5
1.3 Conventions and abbreviations...............................................................................................5
2NMEA Messages..............................................................................................................6
2.1 General Format of NMEA Messages.......................................................................................6
2.2 General Type of NMEA Messages ..........................................................................................7
2.3 NmeaVer h51 ..........................................................................................................................7
2.3.1 Message ID GGA: GNSS Positioning Data......................................................................7
2.3.2 Message ID GLL: GNSS Eographic Longitude/Latitude...................................................8
2.3.3 Message ID GSA: GNSS Dilution of Precision and Effective Satellite Information...........9
2.3.4 Message ID GSV: Visible GNSS Satellites..................................................................... 11
2.3.5 Message ID RMC: The Minimum Recommended Data..................................................12
2.3.6 Message ID VTG: Track Direction and Ground Speed...................................................13
2.3.7 Message ID ZDA: Output Date and Time.......................................................................14
2.3.8 Message ID GST: Output GNSS Pseudorange Error.....................................................15
2.4 NmeaVer h30 ........................................................................................................................16
2.4.1 Message ID GGA: Output GNSS Positioning Data ........................................................16
2.4.2 Message ID GLL: Output Eographic Longitude/Latitude................................................17
2.4.3 Message ID GSA: Output GNSS Dilution of Precision and Effective Satellite Information
18
2.4.4 Message ID GSV: Output Visible GNSS Satellites.........................................................19
2.4.5 Message ID RMC: Output the Minimum Recommended Data.......................................20
2.4.6 Message ID VTG: Output Track Direction and Ground Speed.......................................21
2.4.7 Message ID ZDA: Output Date and Time.......................................................................22
2.5 Navigation Result Message...................................................................................................23
2.5.1 NAVPOS: Output the Receiver Position Information......................................................23
2.5.2 NAVVEL: Output the Receiver Velocity Information .......................................................23
2.5.3 NAVTIME: Output Time Information...............................................................................24
2.5.4 NAVACC: Output Accuracy Information of Receiver Positioning Speed Measurement..25

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1 Introduction
1.1 Purpose of the document
At present, has been built and is planning the construction of a satellite navigation system apart from United
States GPS system, and Russia’s GLONASS system, the European Galileo system, Beidou satellite
navigation system in China and Japan and Indian regional satellite navigation systems.
Based on module AT command manual, this document will introduce GNSS NEMA Message application
process.
Developers could understand and develop application quickly and efficiently based on this document.
1.2 Related documents
1.3 Conventions and abbreviations

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2 NMEA Messages
2.1 General Format of NMEA Messages
NMEA messages use the ASCII character set and have a defined format. Each message begins with a
$ (hex 0x24) and end with a carriage return and line feed (hex 0x0D 0x0A, represented as <CR><LF>).
Each message consists of one or more fields of ASCII letters and numbers, separated by commas. After the
last field, and before the <CR><LF> is a checksum consisting of an asterisk (*, hex 0x2A) followed by two
ASCII characters representing the hexadecimal value of the checksum.
Parameter
Example
Contents
Start $GPGGA Message Identifier. Input messages begin at MID 100
Payload <Data>
Message specific data. Refer to a specific message section for
<data>...<data> definition
Checksum *CKSUM CKSUM is a two-hex ASCII character. Checksums is required in all
input messages
End <CR> <LF> Each message is terminated using Carriage Return (CR) Line Feed
(LF) which are \r\n. Because \r\n are not printable ASCII characters,
they are omitted from the example strings, but must be sent to
terminate the message and cause the receiver to process that input
message
All fields in all
proprietary NMEA messages are required, none are optional and are comma
delimited
In some numeric fields representing a single data element, leading zeros before a decimal are
suppressed. A single "0" character preceding the decimal point is maintained. In compound
numeric structures (such as LAT or LONG), leading zeros are suppressed only on the leftmost
element Trailing zeros are not suppressed
NOTE

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2.2 General Type of NMEA Messages
The message format described in this section is for the versions shown as below:
The version of Beidou related messages extended on the basis of NMEA 3.0 (nmeaVer in CFGNMEA
command is h30)
The version of Beidou related messages extended on the basis of standardNMEA4.1 ($GBGSA, nmeaVer
in CFGNMEA command is h51)
The version of Beidou related messages extended on the basis of standardNMEA4.1 ($BDGSA, nmeaVer
in CFGNMEA command is h52)
BD3 satellites are involved in NMEA4.1 to support BDS satellites with number of 1~37.With the increasing
of satellites, only output GGA, GSV, GSA and RMC messages by default to prevent data loss at the rate of
9600. When the amount of data at 9600 baud rate is allowed, the maximum number of satellites will be
output, but it is limited to the amount of output data at 9600 baud rate. Under the strong sky signal, there will
be a phenomenon of incomplete output of the number of satellites. If the user opens other sentences,
priority is given to ensuring the complete output of the message added by the user. The number of satellites
and satellite information in the GSV message will be reduced accordingly
The baud rate of 115200 is supported, which is able to output all satellite information, and the default output
messages include GGA, GSV, GSA and RMC after switching. If other messages are required, send the
command separately
2.3 NmeaVer h51
2.3.1 Message ID GGA: GNSS Positioning Data
Syntax:$GGA,time,Lat,N,Lon,E,FS,NoSV,HDOP,msl,M,Altref,M,DiffAge,DiffStation*cs
Example:$GPGSA,A,3,07,02,26,27,09,04,15, , , , , ,1.8,1.0,1.5*33<CR><LF>
Parameter Format Description
-- STR
Positioning system flag
GP GPS+SBAS+QZSS joint positioning(1)
GB BDS system standalone positioning
GN Multiple system joint positioning
time STR
UTC time, in the format of hhmmss.ss
hh Hour
mm Minutes
ss.ss Seconds
Lat STR Latitude, in the format of ddmm.mmmmm dd Degrees
mm.mmmmm Minutes
N STR North or south latitude indicator

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N North latitude
S South latitude
Lon STR Longitude, in the format of dddmm.mmmmm ddd Degrees
mm.mmmmm Minutes
E STR East longitude or west longitude indicator E East longitude
W West longitude
FS UINT
Positioning status indicator
0 Invalid
1Point positioning
2 Differential positioning
6 INS positioning
NoSV UINT Number of satellites participating in positioning
HDOP DOUBLE Horizontal dilution of precision, 0
.00 ~ 99.99, the value is
99.99 when not positioning
msl DOUBLE Ellipsoid height, fixed output one decimal place or altitude
(CFGGEOID is set to 1)
M STR Unit of ellipsoid height or altitude, specified to constant M.
The field is empty when not positioning
Altref DOUBLE Sea level separation, fixed output one decimal place. Only valid
when CFGGEOID is set to 1, otherwise it is fixed to
empty.
M STR Unit of sea level separation, specified to constant M.
The field is empty when not positioning
DiffAge DOUBLE Differential correction latency in seconds
Null for non-differential positioning
DiffStation DOUBLE Reference station ID
Null for non-differential positioning
cs STR
Checksum
A hexadecimal number obtained by calculating an XOR of
all
characters from '$' to '*' in this statement
<CR><LF> End of message termination
(1): GPS+SBAS+QZSS joint positioning is only supported by firmware with the version of R3.4.0.0 or
above
2.3.2 Message ID GLL: GNSS Eographic Longitude/Latitude
Syntax:$GLL,Lat,N,Lon,E,time,Valid,Mode*cs
NOTE

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Example:$GPGLL,4004.74005,N,11614.19613,E,060845.00,A,A*6F
Parameter Format Description
-- STR
Positioning system flag
GP GPS+SBAS+QZSS joint positioning(1)
GB BDS system standalone positioning
GN Multiple system joint positioning
Lat STR Latitude, in the format of ddmm.mmmmm dd Degrees
mm.mmmmm Minutes
N STR North or south latitude indicator N North latitude
S South latitude
Lon STR Longitude, in the format of dddmm.mmmmm ddd Degrees
mm.mmmmm Minutes
E STR East longitude or west longitude indicator E East longitude
W West longitude
time STR
UTC time, in the format of hhmmss.ss
hh Hours
mm Minutes
ss.ss Seconds
Valid STR Position valid indicator V Invalid
A Valid
Mode STR
Positioning system mode indicator
N Not positioning
A Point positioning
D Differential positioning
EINS positioning
cs STR Checksum A hexadecimal number obtained by calculating an
XOR of
all characters from '$' to '*' in this statement
<CR><LF> End of message termination
(1): GPS+SBAS+QZSS joint positioning is only supported by firmware with the version of R3.4.0.0 or
above
2.3.3 Message ID GSA: GNSS Dilution of Precision and Effective Satellite Information
Syntax:$GSA,Smode,FS,sv1,sv2,sv3,sv4,sv5,sv6,sv7,sv8,sv9,sv10,sv11,sv12,PDOP,HDOP,VDO
NOTE

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P, systemID*cs
Example:$GPGSA,A,3,02,03,06,09,12,17,19,23,28,25,,,1.34,0.85,1.04,1*1E
Parameter Format Description
-- STR
Positioning system flag
GP GPS+SBAS+QZSS joint positioning(1)
GB BDS system standalone positioning
GN Multiple system joint positioning
Smode STR Positioning mode specified states MManually specify 2D or 3D positioning
AAutomatically switch to 2D or 3D positioning
FS UINT
Positioning mode
1Not positioning
22D positioning or INS positioning
33D positioning
sv1~sv12 UINT
Participating satellite ID
When there are less than 12 satellites participating in the
positioning, the insufficient area is filled in empty and it only
outputs the first 12 satel
lites if there are more than 12
satellites
GPS satellite ID is 01~32
BDS satellite ID is 01~37
GLONASS satellite ID is 65~92(2)
Galileo satellite ID is 01~36(3)
QZSS satellite ID is 193, 194, 195, 199(4)
SBAS satellite ID is 33~51(5)
PDOP DOUBLE Position dilution of precision, 0.00~99.99, the value is 99.99
when not positioning
HDOP DOUBLE Horizontal dilution of precision, 0
.00~99.99, the value is
99.99 when not positioning
VDOP DOUBLE Vertical dilution of precision, 0.00~99.99, the value is 99.99
when not positioning
systemID UINT
GNSS system ID as defined by the NMEA protocol
1GPS system ID
2GLONASS system ID(6)
3Galileo system ID(7)
4BDS system ID
cs STR Checksum A hexadecimal number obtained by calculating an XOR of
all characters from '$' to '*' in this statement
<CR><LF> End of message termination
(1): GPS+SBAS+QZSS joint positioning is only supported by firmware with the version of R3.4.0.0
or above
NOTE

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(2) (3) (4) (5) (6) (7): Only supported by firmware with the version of R3.4.0.0 or above
2.3.4 Message ID GSV: Visible GNSS Satellites
Syntax:$GSV,NoMsg,MsgNo,NoSv,sv1,elv1,az1,cno1,sv2,elv2,az2,cno2,sv3,elv3,az3,cno3,sv4,el
v4,az4,cno4,signalID*cs
Example:
$GPGSV,3,01,11,02,34,277,41,03,16,043,35,05,04,215,35,06,69,333,48,0*57
$GPGSV,3,02,11,09,25,110,41,12,31,305,43,17,55,116,46,19,76,088,46,0*56
$GPGSV,3,03,11,23,23,077,40,25,04,328,32,28,05,171,36,0*67
$GBGSV,3,01,12,01,37,145,42,02,34,225,39,03,44,188,42,04,25,123,37,0*4C
$GBGSV,3,02,12,05,17,249,36,06,30,169,38,07,03,188,31,08,69,027,43,0*4E
$GBGSV,3,03,12,09,09,186,34,10,15,211,36,12,26,306,40,13,60,316,44,0*48
Parameter Format Description
-- STR
System identification
GP GPS satellite information
GB BDS satellite information
GL GLONASS satellite Information(1)
GA Galileo satellite Information(2)
NoMsg UINT
Total number of GSV messages,
the minimum value is 1
NoMsg is the total number of G
SV messages in this
system, for example:
NoMsg in GPGSV is the
total number of GPGSV
messages, excluding the number of GBGSV messages
MsgNo UINT Number of this GSV m
essage. The minimum value is
1.MsgNo is the number of the GSV message in this system
NoSv UINT Total number of visible satellites in this system
sv1~sv4 UINT
Satellite number of the first to fourth satellite
GPS satellite number is 01~32
BDS satellite number is 01~14
GLONASS satellite number is 65~92(3)
Galileo satellite number is 01~36(4)
QZSS satellite number is 193, 194, 195, 199(5)
SBAS (6):
WAAS satellite number is 53, 55, 58
EGNOS satellite number is 40, 44, 46
MSAS satellite number is 49, 57
GAGAN satellite number is 47, 48
elv1~elv4 UINT Elevation angle of the first to fou
rth satellite (0~90
degrees),fixed
output of 2 digits, add zero up front if less
than 2 bits
az1~az4 UINT Azimuth of the first to fourth satellite (0~359 degrees), fixed
output of 3 digits, add zero up front if less than 3 bits

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cno1~cno4 UINT CNR of the first to fourth satellite (0~90dBHz), fixed output of 2 digits, add zero up front if less than 2 bits
fill null for untracked satellites
signalID UINT Signal ID defined by NMEA protocol (fixedly output 0)
cs STR Checksum A hexadecimal number obtained by calculating an XOR of
all characters from '$' to '*' in this statement
<CR><LF> End of message termination
(1) (2) (3) (4) (5) (6): Only supported by firmware with the version of R3.4.0.0 or above
Due to the excessive number of satellites in GN mode, at 9600 baud rate, GSV will have the problem of
incomplete printing of satellite information. For complete satellite information, please switch the baud
rate to 115200
2.3.5 Message ID RMC: The Minimum Recommended Data
Syntax:$RMC,time,status,Lat,N,Lon,E,spd,cog,date,mv,mvE,mode,navStates*cs
Example:$GPRMC,060845.00,A,4004.74005,N,11614.19613,E,0.000,,180817,,,A,V*0B
Parameter Format Description
-- STR
Positioning system flag
GP GPS+ SBAS+QZSS joint positioning(1)
GB BDS system standalone positioning
GN Multiple system joint positioning
time STR
UTC time, in the format of hhmmss.ss
Hh Hours
Mm Minutes
ss.ss Seconds
status STR Position valid indicator V Invalid
A Valid
Lat STR Latitude, in the format of ddmm.mmmmm dd Degrees
mm.mmmmm Minutes
N STR North or south latitude indicator N North latitude
S South latitude
Lon STR Longitude, in the format of dddmm.mmmmm ddd Degrees
mm.mmmmm Minutes
E STR East longitude or west longitude indicator
E East longitude
NOTE

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W West longitude
spd DOUBLE Speed over ground, unit: knot, fixed output of three decimal
places
cog DOUBLE Course over ground, unit: degree
Calculated clockwise from north
date STR
UTC date, in the format of ddmmyy
dd Day
mm Month
yy Year
mv DOUBLE Magnetic declination, specified to null
mvE STR Magnetic declination direction, specified to null
mode STR
Positioning mode
N Not positioning
A Point positioning
D Differential positioning
EINS positioning
navStates STR Navigation states flag, fixedly output ‘V’
VDevice does not provide navigation state information
cs STR Checksum A hexadecimal number obtained by calculating an XOR of
all characters from '$' to '*' in this statement
<CR><LF> End of message termination
(1): GPS+SBAS+QZSS joint positioning is only supported by firmware with the version of R3.4.0.0 or
above
2.3.6 Message ID VTG: Track Direction and Ground Speed
Syntax:$--VTG,cogt,T,cogm,M,sog,N,kph,K,mode*cs
Example:$GPVTG,,T,,M,0.000,N,0.000,K,A*23
Parameter Format Description
-- STR
Positioning system flag
GP GPS+ SBAS+QZSS joint positioning(1)
GB BDS system standalone positioning
GN Multiple system joint positioning
cogt DOUBLE Course over ground with r
eference to true north
(0.000~359.999 degrees)
T STR Course flag, specified to constant T
cogm DOUBLE Course over ground with reference to MN (0.000~359.999
degrees). The field is empty by default
M STR Course flag, specified to constant M
NOTE

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sog DOUBLE Speed over ground, unit: knot
N STR Unit of speed, specified to constant N
kph DOUBLE Speed over ground, unit: km/h
K STR Unit of speed, specified to constant K
mode STR
Positioning mode
N Not positioning
A Point positioning
D Differential positioning
EINS positioning
cs STR Checksum A hexadecimal number obtained by calculating an XOR of
all characters from '$' to '*' in this statement
<CR><LF> End of message termination
(1): GPS+SBAS+QZSS joint positioning is only supported by firmware with the version of R3.4.0.0 or
above
2.3.7 Message ID ZDA: Output Date and Time
Syntax:$ZDA,time,day,mon,year,ltzh,ltzn*cs
Example:$GPZDA,060845.00,18,08,2017,00,00*6C
Parameter Format Description
-- STR
Positioning system flag
GP GPS+ SBAS+QZSS joint positioning(1)
GB BDS system standalone positioning
GN Multiple system joint positioning
time STR
UTC time, in the format of hhmmss.ss
hh Hours
mm Minutes
ss.ss Seconds
day UINT UTC day with two digits, 01~31
mon UINT UTC month with two digits, 01~12
year UINT UTC year with four digits
ltzh UINT Hours in local time zone (fixed output 00)
ltzn UINT Minutes in local time zone (fixed output 00)
cs STR Checksum A hexadecimal number obtained by calculating an XOR of
all characters from '$' to '*' in this statement
<CR><LF> End of message termination
NOTE

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(1): GPS+SBAS+QZSS joint positioning is only supported by firmware with the version of R3.4.0.0 or
above
2.3.8 Message ID GST: Output GNSS Pseudorange Error
Syntax:$GST,time,rngRMS,stdMajor,stdMinor,hdg,stdLat,stdLon,stdAlt*cs
Example:$GPGST,060845.00,0.6,,,,0.07,0.09,0.09*47
Parameter Format Description
-- STR
Positioning system flag
GP GPS+ SBAS+QZSS joint positioning(1)
GB BDS system standalone positioning
GN Multiple system joint positioning
time STR
UTC time, in the format of hhmmss.ss
hh Hours
mm Minutes
ss.ss Seconds
rngRMS DOUBLE Mean square error of pseudo range error in meters, with a
maximum of 3750000
stdMajor DOUBLE Semi-major axis of the error ellipse, in meters.
Specified to null
stdMinor DOUBLE Semi-minor axis of the error ellipse, in meters.
Specified to null
hdg DOUBLE Semi-major axis direction of the error ellipse in degrees,
clockwise from north. Specified to null
stdLat DOUBLE
The mean square error along the latitudinal direction, in
meters
stdLon DOUBLE The mean square error along the longitudinal direction, in
meters
stdAlt DOUBLE
The mean square error along the altitudinal direction, in
meters
cs STR Checksum A hexadecimal number obtained by calculating an XOR of
all characters from '$' to '*' in this statement
<CR><LF> End of message termination
(1): GPS+SBAS+QZSS joint positioning is only supported by firmware with the version of R3.4.0.0 or
above
NOTE
NOTE

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2.4 NmeaVer h30
2.4.1 Message ID GGA: Output GNSS Positioning Data
Syntax:$GGA,time,Lat,N,Lon,E,FS,NoSV,HDOP,msl,M,Altref,M,DiffAge,DiffStation*cs
Example:$GPGGA,063952.000,4002.229934,N,11618.096855,E,1,4,2.788,37.254,M,0
,M,,*71
Parameter Format Description
-- STR
Positioning system flag
GP GPS+ SBAS+QZSS joint positioning(1)
GB BDS system standalone positioning
GN Multiple system joint positioning
time STR
UTC time, in the format of hhmmss.sss
hh Hours
mm Minutes
ss.sss Seconds
Lat STR Latitude, in the format of ddmm.mmmmmm dd Degrees
mm.mmmmmm Minutes
N STR North or south latitude indicator N North latitude
S South latitude
Lon STR Longitude, in the format of dddmm.mmmmmm ddd Degrees
mm.mmmmmm Minutes
E STR East longitude or west longitude indicator E East longitude
W West longitude
FS UINT
Positioning status indicator
0Invalid
1Point positioning
2Differential positioning
6INS positioning
NoSV UINT Number of satellites participating in positioning
HDOP DOUBLE Horizontal dilution of precision, 0.0~127.000
Msl DOUBLE Ellipsoid height, fixed outpu
t one decimal place or altitude
(CFGGEOID is set to 1)
M STR Unit of ellipsoid height or altitude, specified to constant M.
This field is empty when not positioning.
Altref DOUBLE Sea level separation, fixed output one decimal place. Only valid
when CFGGEOID is set to 1, otherwise it is fixed to
empty.
M STR Unit of sea level separation, specified to constant M. The
field is empty when not positioning

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DiffAge DOUBLE Differential correction latency in seconds
Null for
non-differential positioning
DiffStation DOUBLE Reference station ID
Null for non-differential positioning
cs STR Checksum A hexadecimal number obtained by calculating an XOR of
all characters from '$' to '*' in this statement
<CR><LF> End of message termination
(1): GPS+SBAS+QZSS joint positioning is only supported by firmware with the version of R3.4.0.0 or
above
2.4.2 Message ID GLL: Output Eographic Longitude/Latitude
Syntax:$GLL,Lat,N,Lon,E,time,Valid,Mode*cs
Example:$GPGLL,4002.217867,N,11618.105743,E,123400.000,A,A*5B
Parameter Format Description
-- STR
Positioning system flag
GP GPS+ SBAS+QZSS joint positioning(1)
GB BDS system standalone positioning
GN Multiple system joint positioning
Lat STR Latitude, in the format of ddmm.mmmmmm dd Degrees
mm.mmmmmm Minutes
N STR North or south latitude indicator N North latitude
S South latitude
Lon STR Longitude, in the format of dddmm.mmmmmm ddd Degrees
mm.mmmmmm Minutes
E STR East longitude or west longitude indicator E East longitude
W West longitude
time STR
UTC time, in the format of hhmmss.sss
hh Hours
mm Minutes
ss.sss Seconds
Valid STR Position valid indicator V Invalid
A Valid
Mode STR Positioning mode
NOTE

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V Invalid
A Valid
cs STR Checksum A hexadecimal number obtained by calculating an XOR of
all characters from '$' to '*' in this statement
<CR><LF> End of message termination
(1): GPS+SBAS+QZSS joint positioning is only supported by firmware with the version of R3.4.0.0 or
above
2.4.3 Message ID GSA: Output GNSS Dilution of Precision and Effective Satellite
Information
Syntax:GSA,Smode,FS,sv1,sv2,sv3,sv4,sv5,sv6,sv7,sv8,sv9,sv10,sv11,sv12,PDOP,HDOP,VDOP
*cs
Example:$GPGSA,A,3,14,22,18,31,,,,,,,,,5.572,2.788,4.824*36
Parameter Format Description
-- STR
Positioning system flag
GP GPS+Galileo+SBAS+QZSS joint positioning(1)
BD BDS system standalone positioning
GN Multiple system joint positioning
Smode STR Positioning mode specified states M Manually specify 2D or 3D positioning
A Automatically switch to 2D or 3D positioning
FS UINT
Positioning mode
1Not positioning
22D positioning or INS positioning
33D positioning
sv1~sv12 UINT
Participating satellite ID
When there are less than 12
satellites participating in the
positioning, the insufficient area is filled in empty and it only
output the first 12 satel
lites if there are more than 12
satellites
GPS satellite ID is 1~32
BDS satellite ID is 161~197 (160 + BDS PRN)
GLONASS satellite ID is 65~92(2)
Galileo satellite ID is 101~136(3)
QZSS satellite ID is 193, 194, 195, 199(4)
SBAS satellite ID is 33~51(5)
PDOP DOUBLE Position dilution of precision, 0.0~127.000
HDOP DOUBLE Horizontal dilution of precision, 0.0~127.000
NOTE

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VDOP DOUBLE Vertical dilution of precision, 0.0~127.000
cs STR Checksum A hexadecimal number obtained by calculating an XOR of
all characters from '$' to '*' in this statement
<CR><LF> End of message termination
(1): GPS+SBAS+QZSS joint positioning is only supported by firmware with the version of R3.4.0.0 or
above.
(2) (3) (4) (5): Only supported by firmware with the version of R3.4.0.0 or above
2.4.4 Message ID GSV: Output Visible GNSS Satellites
Syntax:$GSV,NoMsg,MsgNo,NoSv,sv1,elv1,az1,cno1,sv2,elv2,az2,cno2,sv3,elv3,az3,
cno3,sv4,elv4,az4,cno4*cs
Example:
$GPGSV,3,1,11,3,82,133,50,6,70,73,50,7,21,311,45,13,46,275,50*75
$GPGSV,3,2,11,16,52,51,49,19,52,194,49,21,12,49,37,23,40,222,49*7C
$GPGSV,3,3,11,30,31,69,46,31,8,127,19,1,5,,44*77
$BDGSV,2,1,5,161,35,140,47,163,33,224,47,164,24,124,43,167,47,73,48*54
$BDGSV,2,2,5,168,5,,50*52
Parameter Format Description
-- STR
Positioning system flag
GP GPS+SBAS+QZSS joint positioning(1)
BD BDS system standalone positioning
GN Multiple system joint positioning
NoMsg UINT
Total number of GSV messages, the minimum
value is 1
NoMsg is the total number of G
SV messages in this
system, for example:
NoMsg in GPGSV is the
total number of GPGSV
messages, excluding the number of BDGSV messages
MsgNo UINT
Number of this GSV m
essage. The minimum value is
1.MsgNo is the number of t
his GSV message in this
system.
Continuous output GPGSV and BDGSV are
numbered separately
NoSv UINT
Total number of visible satellites in this system
GLONASS satellite number is 65~ 92(2)
Galileo satellite number is 101~136(3)
QZSS satellite number is 193, 194, 195, 199(4)
SBAS (5):
WAAS satellite number is 53, 55, 58
EGNOS satellite number is 40, 44, 46
NOTE

SIM66 Series_NMEA Message_User Guide_V1.01
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MSAS satellite number is 49, 57
GAGAN satellite number is 47, 48
elv1~elv4 UINT Elevation of the first to fourth satellite (0 ~ 90 degrees)
az1~az4 UINT Azimuth of the first to fourth satellite (0 ~ 359 degrees)
cno1~cno4 UINT CNR of the 1st to 4th satelli
tes (0 ~ 90dBHz), fill null for
untracked satellites
cs STR Checksum A hexadecimal number obtained by calculating an XOR of
all characters from '$' to '*' in this statement
<CR><LF> End of message termination
(1): GPS+SBAS+QZSS joint positioning is only supported by firmware with the version of R3.4.0.0 or
above.
(2) (3) (4) (5): Only supported by firmware with the version of R3.4.0.0 or above
Due to the excessive number of satellites in GN mode, GSV at 9600 baud rate will have
the problem of incomplete printing of satellite information. For complete satellite
information, please switch the baud rate to 115200
2.4.5 Message ID RMC: Output the Minimum Recommended Data
Syntax:$RMC,time,status,Lat,N,Lon,E,spd,cog,date,mv,mvE,mode*cs
Example:$GPRMC,123400.000,A,4002.217821,N,11618.105743,E,0.026,181.631,180411,,E,A*2C
Parameter Format Description
-- STR
Positioning system flag
GP GPS+SBAS+QZSS joint positioning
BD BDS system standalone positioning
GN Multiple system joint positioning
time STR
UTC time, in the format of hhmmss.sss
hh Hours
mm Minutes
ss.sss Seconds
status STR Position valid indicator V Invalid
A Valid
Lat STR Latitude, in the format of ddmm.mmmmmm dd Degrees
mm.mmmmmm Minutes
N STR North or south latitude indicator N North latitude
S South latitude
NOTE