SiRFstarIII GSD3tw

This single die, small footprint implementation of SIRFstarIII™ architecture provides a cost-effective solution for high-volume embedded applications where host processor resources are available to execute SiRFNav®— SiRF’s high performance navigation software suite, providing Autonomous navigation, Aided-GPS navigation (both user plane and control plane), and SiRFInstantFix™ technology. This 90 nm single-die IC has fully integrated 1.2 V LDOs, reducing the external Bill of Materials.

GENERAL SPECIFICATIONS
Supported Software
Standard
SiRFTrackIII™ GPS tracker software
SiRFNavIII™ standalone GPS navigation software
Premium
SiRFLoc® Client (SLC) A-GPS software- SiRFNavIII A-GPS navigation software - SiRFLocStack™ location protocol library for user plane (SUPL) and control plane (RRLP, RRC) A-GPS
SiRFInstantFix extended ephemeris software; connectivity optional
Smallest Footprint Package
Type: 49-pin WLCSP with a ball pitch of 0.4 mm
Dimensions: 3.12 mm x 3.17 mm; Height: 0.68 mm
Typical total solution footprint: 30 mm2
Low Production Cost Package
Type: 49-pin TFBGA with a ball pitch of 0.5 mm
Dimensions: 4 mm x 4.5 mm; Height: 0.68 mm
Typical total solution footprint: 40 mm2

KEY FEATURES
Single die SiRFstarIII proprietary Satellite Signal Processor technology
High sensitivity signal acquisition capability (Aided-GPS)
Integrated ROM and controller to minimize host platform loading
90 nm RFCMOS for cost effective baseband + RF integration
On-chip LNA reduces total solution cost and footprint
Extremely low power
Reduced pin count and small package size simplifies PCB layout
TCXO power supply control through integrated FET switch
GPS Architecture Highlights
Premium SiRFstarIII architecture with 200,000+ effective correlators for fast TTFF and high sensitivity acquisition
GPS Features
SiRFNav host software with: real-time navigation for location based services
Advanced Power Management and Adaptive TricklePower™ plus low energy-per-fix in point position applications
Multimode A-GPS support: Autonomous, MS Based, MS Assisted
Location protocol libraries supporting RRC, RRLP, 3GPP2, SUPL, E-911

TECHNICAL SPECIFICATIONS
Horizontal Position Accuracy 1 • Autonomous <2.5>

HIGHLIGHTED ADVANTAGES
For cellular handset applications where space is at a premium, the GSD3tw offers two excellent package options; one for low cost production and one for small footprint mainstream design.
The GSD3tw supports SiRFLoc Client, the patented Multimode A-GPS software powering mobile phones optimized for location-enabled services. SiRFLoc improvesGPS location capability in wireless system environments by utilizing various modes of wireless infrastructure assistance to improve weak signal reception.
For personal navigation devices with high-end host processors, the GSD3tw with SiRFNav software provides SiRF Autonomous mode GPS navigation, setting a newperformance benchmark for high-sensitivity navigation.
SiRF’s standard autonomous software also supports SiRFInstantFix technology, which eliminates the initial task of obtaining broadcast GPS data from the satellites themselves, resulting in a faster TTFFs, even in weak signal environments.

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SiRFstarIII GSC3LTi and GSC3LTif Flagship Multimode A-GPS Solution

These tiny dynamos condense SiRFstarIII™ technology into the lowest power, highest performing SiRF solution, and they measure a compact 6x6x1.2 mm—thanks to 90-nanometer technology. Less expensive and 25% smaller and than the GSC3LT, the GSC3LTi is engineered for wireless applications and handheld systems with centralized power management that don’t require a wholly independent, self-managed GPS subsystem power supply. Internal Flash memory is optional (GSC3LTif).

GENERAL SPECIFICATIONS
Supported Software
Standard
GSW3LT Standalone GPS software with SBAS support
Premium
SiRFLoc® Client (SLC) LT A-GPS Multimode Location Engine™ for GSM/3GPP
SiRFLoc Client (SLC) LT A-GPS Multimode Location Engine for CDMA IS-801A with coarse location
SiRFInstantFix™ extended ephemeris service for very fast TTFFs
Package
Type: 120-ball thin profile, fine pitch ball grid array (TFBGA) with a ball pitch of 0.5 mm
Dimensions: 6 mm x 6 mm; Height: 1.2 mm ROM device, 1.4 mm Flash device
Typical total solution footprint: 105 mm2

KEY FEATURES
90 nm SiRFstarIII-LT DSP Core
Navigation Engine (PVT) solution
4 Mbit on-chip ROM program memory
SPI and UART Host interfaces
Up to eight programmable GPIOs
GPS Architecture Highlights
High sensitivity: -159 dBm for indoor fixes
200,000+ effective correlators for very fast TTFF and high sensitivity acquisition
SBAS (WAAS, MSAS, EGNOS) support
GPS Features
Real time navigation for location based services
Low energy-per-fix in point position applicationsLow energy-per-fix in point position applications
Advanced Power Management and Adaptive TricklePower™ plus low energy-per-fix in point position applications
Multimode A-GPS Support: Autonomous, MS Based, MS Assisted
Location protocol libraries supporting RRC, RRLP, 3GPP2, SUPL, E-911

TECHNICAL SPECIFICATIONS
Horizontal Position Accuracy 1 • Autonomous <2.5>

HIGHLIGHTED ADVANTAGES
The GSC3LTi(f) is supported by SiRF standard autonomous software that’s setting new performance benchmarks in the portable navigation systems market. SiRF standard autonomous software also supports recently announced SiRFInstantFix technology, which eliminates the initial task of obtaining broadcast GPS data from the satellites themselves, resulting in a faster Time-To-First-Fix (TTFF), even in weak signal environments.
The GSC3LTi(f) also supports SiRFLoc Client, the patented Multimode A-GPS software powering mobile phones optimized for location-enabled-services. SiRFLoc improves GPS location capability in wireless system environments by utilizing various modes of wireless infrastructure assistance to improve weak signal reception.
The GSC3LTi(f) GPS performance is fully compliant with the industry-standard Third Generation Partnership Project (3GPP) TS25.171 and CDMA TIA916 requirements, with extremely fast assisted fix speeds that are often significantly faster than required by the standard.

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NMEA CONFIG command

4 NMEA Input Commands
Orion may not recognize commands if they are input at a rate greater than one per second.
All commands are in upper case unless stated otherwise.
If valid, the CONFIG, STOP, SLEEP, and START commands will be echoed back to the sender and
GETCONFIG will generate a CFG_R response. Otherwise, an error message will be sent.

4.1 GETCONFIG Command
The GETCONFIG command allows the user to read the current system configuration.
For details of each field, please refer to the CONFIG command in section 4.2 .
The format of the GETCONFIG command is:
$PUNV,GETCONFIG,

*cc
4.1.1 Output Configuration
Read the current output configuration:
$PUNV,GETCONFIG,00*41
The response message is:
$PUNV,CFG_R,00,00,0,1000,UART,MASK,*cc
UART = serial bit rate
MASK = NMEA message mask
4.1.2 Time Zone Configuration
Read the current time zone configuration:
$PUNV,GETCONFIG,03*42
The response message is:
$PUNV,CFG_R,03,TZH,TZM*cc
TZH = Time zone offset hours
TZM = Time zone offset minutes
Command Description
GETCONFIG Read configuration information
CONFIG Set configuration
STOP Stop navigation
SLEEP Stop navigation and enter sleep mode
START Immediate restart

4.1.3 Datum Configuration
Read the current datum configuration:
$PUNV,GETCONFIG,13*43
The response message is:
$PUNV,CFG_R,13,Dx,Dy,Dz,Da,Df,Name,ID*cc
Dx, Dy, Dz = Datum Offset values for X, Y, and Z coordinates (in meters).
Da = Datum value for the semi-major axis (in meters).
Df = Datum value for flattening.
Name = Name of the configured datum (see Section 6 for Datum names & IDs)
ID = ID of the configured datum (see Section 6 for Datum names & IDs).
4.1.4 Position Pinning & 2D/3D Startup Configuration
Read the current Position Pinning and 2D/3D start mode configuration:
$PUNV,GETCONFIG,17*47
The response message is:
$PUNV,CFG_R,17,PosThreshold,VelThreshold,2DStartMode*cc
. PosThreshold = Threshold value (meters) for position jump. Position will not be pinned if
this value is reached.
. VelThreshold = Threshold value (meters/second) for position jump. Position will not be
pinned if this value is reached.
. 2DStartMode = indicates whether the receiver will initially enter 2D fix mode (using last
navigated altitude) during a restart.
o 0: only 3D start is allowed
o 3: enable 2D cold start (if no last known good fix) & auto start (with last known good
fix),
4.1.5 Version Number
Read the software version number:
$PUNV,GETCONFIG,09*48
The response message is:
$PUNV,CFG_R,09,OrionVersion,*cc
OrionVersion is the Orion version string
The remaining values are hardware configuration values.
Note - This message is also sent at power up and reset.
Example-$PUNV,CFG_R,09,1.2.0-432,UBP_1.0,8130,2,1008,1,3,3000,16367600*58
Example-$PUNV,CFG_R,09,1.2.2-499-U121,UBP_1.0,8130,5,1008,1,3,0,16367600*25

4.2 CONFIG Command
The CONFIG command allows the user to change the configuration of the system. This configuration
takes effect immediately. It is also stored in non-volatile media and will therefore persist across
power cycles.
The format of the CONFIG command is:
$PUNV,CONFIG,

,*cc
4.2.1 Section 00 - Output Configuration
Set the output configuration:
$PUNV,CONFIG,00,00,0,1000,UART,MASK*cc
Table 11 – Output Configuration Parameters
UART is the UART communication speed in bits per second. All communications use 8 data
bits, no parity, and one stop bit.
MASK is a two-digit hexadecimal number which enables selected output NMEA sentences.
Each NMEA output sentence is assigned a bit in the mask.
Examples:
Only transmit the GSA, GSV, VTG, ZDA, and DTM sentences:
$EC = GSA ($4) + GSV ($8) + VTG ($20) + ZDA ( $40) + DTM(80)
Transmit the default sentences:
$1D = GGA ($1) + GSA ($4) + GSV ($8) + RMC ($10)
. Orion will check the maximum length of NMEA sentences when changing the output
configuration. If the speed is set to 4800 bps and the selected sentences total more than 450
characters, the command will be rejected and an error message issued. If all the specified
sentences are desired, a speed greater than 4800 bps must be selected.
UART communication speed NMEA mask
(UART) (MASK)
4800 = 4800 bps 01 = GGA
9600 = 9600 bps 02 = GLL
14400 = 14400 bps 04 = GSA
19200 = 19200 bps 08 = GSV
38400 = 38400 bps
57600 = 57600 bps 10 = RMC
115200 = 115200 bps 20 = VTG
40 = ZDA
80 = DTM
Default : 4800 Default : 1D

Examples:
Send all sentences except DTM at 115200 bps:
$PUNV,CONFIG,00,00,0,1000,115200,7F*cc
Change speed to 9600 bps with default output sentences:
$PUNV,CONFIG,00,00,0,1000,9600,1D*70
Disable sending of all NMEA sentences:
$PUNV,CONFIG,00,00,0,1000,4800,0*36
Send the default sentences:
$PUNV,CONFIG,00,00,0,1000,4800,1D*73
4.2.2 Section 03 - Time Zone Offset Configuration
Set the time zone offset:
$PUNV,CONFIG,03,TZH,TZM*cc
Table 12 – Time Zone Offset Configuration Parameters
TZH is the UTC offset in whole hours.
It may be negative, zero, or positive and is generally negative for West longitudes.
TZM is the additional minutes of UTC offset.
It must be zero or positive.
Note that this time zone offset has no effect on the timestamps in NMEA sentences which are always
in UTC.
Examples:
Set the -8 hour time zone (U. S. Pacific Standard Time):
$PUNV,CONFIG,03,-8,0*31
Set the UTC time zone (no offset):
$PUNV,CONFIG,03,0,0*14
Time Zone Offset Hours Time Zone Offset Minutes
(TZH) (TZM)
-11, -10, … , -1, 0, 1, … , 12 0, 15, 30, 45
Default : not set (0) Default : not set (0)

4.2.3 Datum Configuration
a. Set a built-in datum:
$PUNV,CONFIG,16,ID*cc
ID is the ID of the desired datum.
Default is 1 (WGS-84).
b. Set a custom datum configuration:
$PUNV,CONFIG,13,Dx,Dy,Dz,Da,Df,Name,0*cc
Dx, Dy, and Dz are the X, Y, and Z coordinate offsets in meters.
The defaults are 0.0, 0.0, 0.0 .
Da is the semi-major axis in meters. The default is 6378137.
Df is the flattening coefficient. The default is 0.003352810664 .
Name is the name of the datum. Maximum is 8 characters.
Examples:
Select the “TOY-B” (South Korean) datum:
$PUNV,CONFIG,16,211*0E
Select the default datum (WGS-84):
$PUNV,CONFIG,16,1*0D
4.2.4 Position Pinning & 2D/3D Startup
Set position pinning and 2D/3D startup parameters:
$PUNV,CONFIG,17,PosThreshold,VelThreshold,2D/3DStartMode*cc
PosThreshold is the threshold value for position jump. Position pinning will be disabled if
this value is reached.
VelThreshold is the threshold value for velocity calculation. Position pinning will be disabled
if this value is reached.
2DStartMode indicates whether the receiver will enter 2D startup initially during a cold start
based upon last navigated altitude.

Example:
Set the default settings:
$PUNV,CONFIG,17,50.0,1.0,3*3A
2D/3D Start Mode
0 = only 3D startup allowed
1 = Reserved. Do not use
2 = Reserved. Do not use
3 = 2D startup is allowed
Default: 3

4.3 STOP Command
Stop navigation:
$PUNV,STOP*29
4.4 SLEEP Command
Enter the sleep mode:
$PUNV,SLEEP*7E
To wake up from sleep, send a command to the serial port. Since the command will not be executed,
its content is arbitrary. Orion always wakes in the AUTO mode.
If the board design includes an external RTC (please refer to the module Data Sheet), the
SLEEP command can specify a sleep duration. Note that the receiver will wake up on
UART activity or when the duration expires, whichever occurs first.
$PUNV,SLEEP,HH,MM,SS*CC
HH is hours [0 to 24]
MM is minutes [0 to 59]
DD is seconds [0 to 59]
Maximum sleep time is 24,59,59 and minimum is 00,00,05.
Example (sleep for 30 seconds):
$PUNV,SLEEP,00,00,30*cc
4.5 START Commands
Cause an immediate restart:
$PUNV,START,AUTO*52
$PUNV,START,COLD*59
$PUNV,START,WARM*59
$PUNV,START,HOT*0E
$PUNV,START,FAST*5D
The START command will be echoed only after the system has stopped (which takes approximately
one second). Until then Orion will produce navigation data.

5 ERR Message
The ERR message is sent as a response to an invalid command. Its format is:
$PUNV,ERR,ID,ERROR,DATA*cc
ID is the section ID which causes the error (05 = NMEA command processor).
ERROR is the error number defined in the section.
DATA is error specific optional data.
ID ERROR Description
5 (NMEA) 1 Illegal command form
5 (NMEA) 2 Illegal command prefix
5 (NMEA) 3 Illegal command
5 (NMEA) 4 Illegal section ID
5 (NMEA) 5 Illegal parameter.
5 (NMEA) 6 Illegal checksum.
5 (NMEA) 7 Illegal message.
Table 15 – Error Codes
Examples of error messages:
Illegal checksum:
$PUNV,ERR,05,00006,00000*5B
Illegal command:
$PUNV,ERR,05,00003,00000*5E
Fast Hot Warm Cold
Almanac + + + -
Ephemeris + + - -
Time accuracy ~10 ms ~300s ~300s -
Last known good fix + + + -

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Orion NMEA-0183 message

1 Overview
This document describes the format and usage of NMEA messages for Orion GPS navigation software. It also details the implementation specifics of NMEA input commands and output sentences supported by Orion.

2 Message Format
Orion NMEA messages conform to the NMEA-0183 Ver. 3.01 (January 1, 2002) standard with implementation specifics as noted below. Commands start with a dollar-sign (“$”), followed by “PUNV”, and a comma (“,”). The command text comes next, followed by an asterisk (“*”), two-digit hexadecimal checksum, and the characters.

Example:
$PUNV,*cc
2.1 Checksum Calculation
In accordance with NMEA-0183, the checksum is calculated by taking the 8 bit exclusive OR of all characters between (but not including) the “$” and the “*”. The checksum is then appended after the “*” as a 2 character hexadecimal number.
If a command’s checksum is omitted or illegal the command will be rejected and an error message issued.
A command with the checksum value “cc” (two lower case “c” characters) will be accepted as valid (this is primarily used for testing purposes).
2.2 Sentence Termination Delimiter
All sentences end with the sentence termination delimiter . This combination is “\r\n” in C-language format and hexadecimal ASCII values are 0Dh 0Ah. Both characters are required for a command to be recognized.
2.3 NMEA Message Sizes
In accordance with NMEA-0183, the maximum number of characters between the starting delimiter
“$” and the terminating should be 79. That is, the maximum needed buffer size should be 82 for one output sentence. For input NMEA commands, the maximum size accepted is 128 characters.

3 Standard NMEA Output Sentences
The following format conventions have been used in accordance with the NMEA standard with implementation specifics noted:
. When a data field is null, the unit of measure field will also be null.
. Three digits are used for decimal fraction of seconds in UTC time.
. Four digits are used for decimal fraction of minutes in latitude and longitude.
. Two digits are used for Satellite IDs, with a leading zero if necessary.
. DTM: Six digits are used for decimal fraction of latitude and longitude offsets. Two digits are used for decimal fraction of altitude offset. Datum Subdivision Code is null.
. GGA: UTC starts from zero time and changes to measured time when the fix becomes valid.
Altitude is reported referenced to the ellipsoid, and the Geoidal Separation is null.
. GLL: UTC time field as in GGA.
. GSA: Satellite ID numbers are in the range 00 to 99.
. GSV: No implementation-specific notes.
. RMC: UTC time field as in GGA. Course and Speed over ground as in VTG. Magnetic
Variation is null.
. VTG: Course over ground is reported with 0.1 degree precision, Speed over ground is reported with 0.1 unit precision for both knots and km/h fields. Magnetic Course is null.
. ZDA: Local zone hours are presented as user has configured. Default is null. The hour zone is reported with two digits (with leading zero when necessary), and with leading minus sign when necessary. Local zone minutes are presented as two digits (with leading zero when necessary) and is always zero or positive. UTC time field as in GGA.

Message ID Description Default
DTM Datum reference N
GGA GPS fix data Y
GLL GPS latitude & longitude N
GSA DOP and active satellites Y
GSV Satellites in view Y
RMC Recommended Minimum GNSS Data Y
VTG Course over ground and ground speed N
ZDA Time, date, & local time zone N
Table 1 – Standard NMEA Output Sentences

3.1 DTM – Datum reference
This sentence contains the ID of the datum selected, along with configured offsets.
$GPDTM,W84,,0.000000,S,0.000000,W,0.00,W84*50
Name Description Type Example
MsgID DTM Header $GPDTM
DatumID Local Datum ID W84
DatumSubD Datum Subdivision Code
LatOfs Latitude Offset (in minutes) 0.000000
LatDirection
N = North
S = South
S
LonOfs Longitude Offset (in minutes) 0.000000
LonDirection
E = East
W = West
W
AltOfs Altitude Offset (in meters) 0.00
RefDatum Reference Datum ID W84
ChkSum Checksum *50
EOL NMEA end of line

3.2 GGA – GPS Fix Data
This sentence contains the position, time and quality of the navigation fix.
See RMC for Fix Status, Fix Mode, Fix Date, Speed, and True Course.
See GSA for Fix Type, PDOP, and VDOP.
$GPGGA,042626.001,3345.7471,N,11750.8451,W,1,04,8.7,32.28,M,,,,*16
Name Description Type Example
MsgID GGA Header $GPGGA
FixTime Fix Time (UTC) hh.mmss.sss 042626.001
Lat Latitude ddmm.mmmm 3345.7471
LatDirection
N = North
S = South
Lon Longitude dddmm.mmmm 11750.8451
LonDirection
E = East
W = West
FixQuality
0 = No fix
1 = Valid Fix

3.3 GLL – Geographic Position – Latitude/Longitude
This sentence contains the fix latitude and longitude.
$GPGLL,3345.7471,N,11750.8451,W,042628.001,A,A*4E
Name Description Type Example
MsgID GLL Header $GPGLL
Lat Latitude ddmm.mmmm 3345.7471
LatDirection
N = North
S = South
N
Lon Longitude dddmm.mmmm 11750.8451
LonDirection
E = East
W = West
W
FixTime Fix Time (UTC) hhmmss.sss 042628.001
FixStatus
V = No fix
A = Valid Fix
A
FixMode
N = No Fix
A = Autonomous Mode
A
ChkSum Checksum *4E


3.4 GSA – GNSS DOP and Active Satellites
This sentence contains the mode of operation, type of fix, PRNs of the satellites used in the solution
as well as PDOP, HDOP and VDOP.
$GPGSA,A,3,15,22,18,21,03,14,09,19,16,26,,,1.5,1.0,1.2*3E
Name Description Type Example
MsgID GSA Header $GPGSA
OpMode
A = Automatic
M = Manual (not used by Orion)
A
FixType
1 = No fix
2 = 2D fix
3 = 3D fix
3
SatID01 SV on channel 01 15
… … …
SatID12 SV on channel 12
PDOP Position Dilution of Precision 1.5
HDOP Horizontal Dilution of Precision 1.0
VDOP Vertical Dilution of Precision 1.2
ChkSum Checksum *3E


3.5 GSV – GNSS Satellites in View
This sentence contains the PRNs, azimuth, elevation, and signal strength of all satellites in view.
$GPGSV,3,1,10,03,37,299,47,09,15,094,41,14,34,193,49,15,68,031,52*72
$GPGSV,3,2,10,16,07,242,42,18,58,025,50,19,08,322,40,21,53,086,52*76
$GPGSV,3,3,10,22,62,292,50,26,06,035,37*70
Name Description Type Example
MsgID GSV Header $GPGSV
NumMsgs Total number of GSV sentences 3
MsgNum Sentence number (of the total) 1
NumSatView Number of satellites in view 10
SatID1 SV on channel 1, 5 or 9 03
Elevation1 Elevation (in degrees) 37
Azimuth1 Azimuth (in degrees True) 299
C/No1 C/No of satellite (in dB-Hz) 47
SatID2 SV on channel 2, 6 or 10 09
Elevation2 Elevation 15
Azimuth2 Azimuth 094
C/No2 C/No of satellite 41
SatID3 SV on channel 3, 7 or 11 14
Elevation3 Elevation 34
Azimuth3 Azimuth 193
C/No3 C/No of satellite 49
SatID4 SV on channel 4, 8 or 12 15
Elevation4 Elevation 68
Azimuth4 Azimuth 031
C/No4 C/No of satellite 52
ChkSum Checksum *72

3.6 RMC – Recommended Minimum Specific GNSS Data
This sentence contains the recommended minimum fix information.
See GGA for Fix Quality, Sats Used, HDOP, Altitude, Geoidal Separation, and DGPS data.
See GSA for Fix Type, PDOP and VDOP.
$GPRMC,042626.001,A,3345.7471,N,11750.8451,W,0.0,270.0,140707,,,A*77
Name Description Type Example
MsgID RMC Header $GPRMC
FixTime Fix Time (UTC) hhmmss.sss 042626.001
FixStatus
V = No fix
A = Valid Fix
A
Lat Latitude ddmm.mmmm 3345.7471
LatDirection
N = North
S = South
N
Lon Longitude dddmm.mmmm 11750.8451
LonDirection
E = East
W = West
W
Speed Speed (in knots) 0.0
Tcourse True Course (in degrees) 270.0
FixDate Fix Date (UTC) ddmmyy 140707
MagVar Magnetic Variation (in degrees)
MVdirection Magnetic Variation Direction (E/W)
Fix Mode
N = No fix
A = Autonomous
A
ChkSum Checksum *77


3.7 VTG – Course Over Ground and Ground Speed
This sentence contains the course and speed of the navigation solution.
$GPVTG,270.0,T,,,0.0,N,0.0,K,A*45
Name Description Type Example
MsgID VTG Header $GPVTG
Tcourse True Course (in degrees) 270.0
ReferenceT T = True T
Mcourse Magnetic Course (in degrees)
ReferenceM M = Magnetic
Speed Speed (in knots) 0.0
UnitN N = Knots (Nautical Miles per Hour) N
SpeedKPH Speed (in Kilometers per Hour) 0.0
UnitK K = KPH K
Mode
N = No fix
A = Autonomous
A
ChkSum Checksum *45

3.8 ZDA – Time and Date
This sentence contains UTC date & time, and local time zone offset information.
$GPZDA,042626.001,14,07,2007,,*54
Name Description Type Example
MsgID ZDA Header $GPZDA
Time hhmmss.sss 042626.001
Day Day (UTC) dd 14
Month Month (UTC) mm 07
Year Year (UTC) yyyy 2007
TZH Local Time Zone Offset Hours
TZM Local Time Zone Offset Minutes
ChkSum Checksum *54

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