Globalsat EB-3531 User Manual

Page 1
EB-3531
Version 1.2.1
GPS Engine Board
Globalsat Technology Corporation
16F., No. 186, Jian-Yi Road, Chung-Ho City, Taipei Hsien 235, Taiwan Tel: 886-2-8226-3799/ Fax: 886-2-8226-3899
service@globalsat.com.tw www.globalsat.com.tw
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USGlobalSat, Inc.
4740 Yorba Court, Chino, CA 91710
1 T
909.597.8525 / Fax: 909.597.8532
el:
oem
@usglobalsat.com
www.usglobalsat.com
Specifications are subject to be changed without notice.
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EB-3531
Version 1.2.1
1. Product Information
Product Part I.D. EB-3531
Product Description:
The EB-3531 is a compact, high performance, low power consumption GPS engine board. It
features a SiRF Star III chipset, which can track up to 20 satellites at a time and perform fast
TTFF (time to first fix) in weak signal environments. The EB-3531 is ideal for automotive or
marine navigation, personal positioning, fleet management, and mobile-phone navigation.
Product Features
9 SiRF GSC3f/LP high performance GPS Chipset 9 Very high sensitivity (Tracking Sensitivity: -159 dBm) 9 Extremely fast TTFF (Time To First Fix) at low signal level 9 All-in-view 20-channel parallel processing 9 Two serial ports 9 4Mb flash 9 Built-in LNA 9 Compact size (15mm * 13mm * 2.2mm) suitable for space-sensitive application 9 One size component, easy to mount on another PCB board 9 Support NMEA 0183 and SiRF binary protocol 9 WAAS / EGNOS MSAS support 9 RoHS compliant
Product Specifications
GPS Receiver
Chipset SiRF GSC3f/LP
Frequency L1, 1575.42 MHz
Code C/A Code
Protocol NMEA 0183 v3.0
Available Baud Rate 4,800 to 57,600 bps adjustable
Default:GGA,GSA,GSV,RMC Support:VTG,GLL,ZDA) SiRF binary and NMEA Command
Specifications are subject to be changed without notice.
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EB-3531
Version 1.2.1
Channels 20
Flash 4Mbit
Sensitivity Tracking:-159dBm
Cold Start 42 seconds, average
Warm Start 38 seconds, average
Hot Start 1 second, average
Reacquisition 0.1 second, average
Accuracy Position: 10 meters, 2D RMS
5 meters, 2D RMS, WAAS enabled Velocity: 0.1 m/s Time: 1us synchronized to GPS time
Maximum Altitude 18,000 meter
Maximum Velocity 515 meter/second
Maximum Acceleration 4G
Update Rate 1 Hz
DGPS WAAS, EGNOS, MSAS
Datum WGS-84
Interface
I/O Pins 2 serial ports
Physical Characteristic
Type 22-pin stamp holes
Dimensions 15 mm * 13mm * 2.2 mm ±0.2mm
DC Characteristics
Power Supply 3.3Vdc ± 5%
Backup Voltage 2.0 ~ 3.6Vdc
Power Consumption Acquisition: 60mA
Tracking: 42mA
Environmental Range
Humidity Range 5% to 95% non-condensing
Operation Temperature -30C to 85C
Storage Temperature -40C to 85C
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2. Technical Information
Block Diagram
EB-3531
Version 1.2.1
Module Pin Assignment
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EB-3531
Pin NO. Pin Name I/O Remark
1. RXB I Serial input (default null)
2. TXB O Serial output (default null)
3. TIMEMARK I/O One pulse per second.
4. TXA O Serial output (default NMEA)
5. RXA I Serial input (default NMEA)
6. NC NC
7. GPIO0 I/O General purpose I/O
8. GPIO1 I/O General purpose I/O
9. RF_PWR CTR RF Power ON/OFF.
10. ON_OFF I Edge triggered soft on/off request. It must be low for normal application.
11. VBAT PWR Backup battery supply voltage
12. VCC PWR Main power supply to the engine board.
13. GPIO13 I/O General purpose I/O
14. GPIO14 I/O General purpose I/O
15. GPIO15
16. BOOTSEL I/O Set this pin to high for programming flash.
17. VCC_RF PWR Regulated RF power output.
18. GND G Ground.
19. RF IN RF GPS antenna input.
20. GND G Ground.
21. GND G Ground.
22. GND G Ground.
O GPS status output.
Version 1.2.1
Specifications are subject to be changed without notice.
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Page 6
Application Circuit
TXA
RXA
GPS_3V3
C5
1UF
1 2
1 2
C6
0.1U F
EB-3531
L3
BLM18AG121SN1D
L4
BLM18AG121SN1D
D1
RB521S
R6 270R
1 2
D2
RB512S
1
RXB
2
TXB
3
1PPS
4
TXA
5
RXA
21
GND
6
NC
7
GPIO0
8
GPIO1
9
RF_PWR
10 11
ON_OFF VBAT
M1
EB-3531
GND
RF_IN
GND
VCC_RF
BOOTSEL
GND
GPIO15
GPIO14
GPIO13
VCC
Version 1.2.1
A1
GPS_ANTENNA
1
20
19
18
17
16
22
15
14
13
12
GPS_3V3
C7
10UF
12
BATTERY
MS518S-FL35E
GPS POWER
VIN
C1
22UF/ 10V
U1
1
VIN
2
GND
XC6209B332MRN 3. 3V
VOUT
NCCE
5
43
C2
10UF/ 16V
L1
BLM18AG121SN1D
C3
470PF
GPS Active Antenna Specifications (Recommendation)
Frequency: 1575.42 + 2MHz Axial Ratio: 3 dB Typical Output Impedance: 50 Polarization: RHCP Amplifier Gain: 18~22dB Typical Output VSWR: 2.0 Max. Noise Figure: 2.0 dB Max Antenna Input Voltage: 2.85V (Typ.)
GPS_3V3
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Dimensions
EB-3531
Version 1.2.1
Recommend Layout PAD
Tolerances: ±0.1mm
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Application Guideline
Application Circuit
1.
EB-3531
Version 1.2.1
TXA
RXA
L3
BLM18AG121SN1D
L4
BLM18AG121SN1D
GPS_3V3
C5
1UF
1 2
1 2
C6
0.1UF
1
RXB
2
TXB
3
1PPS
4
TXA
5
RXA
21
GND
6
NC
7
GPIO0
8
GPIO1
9
RF_PWR
10 11
ON_OFF VBAT
D1
RB521S
1 2
12
M1
EB-3531
R6 270R
BATTE RY
MS518S-FL35E
RF_IN
VCC_RF
BOOTSEL
GPIO15
GPIO14
GPIO13
D2
RB512S
50 Ohm Micro strip line
20
GND
19
18
GND
17
16
22
GND
15
14
GPS_3V3
C7
10UF
VCC
13
12
1
1
RF Sw it ch
24-20003-12030N
2
2
50 Ohm Micro strip line
12
J1_I-PEX c onnect
External antenna
2.
VIN
C1
22UF/ 10V
GPS POWER
U1
1
VIN
2
GND
XC 6209B332MRN 3. 3V
5
VOUT
43
NCCE
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BLM18AG121SN1D
C2
10UF/ 16VC3470PF
Specifications are subject to be changed without notice.
L1
GPS_3V3
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EB-3531
Version 1.2.1
Layout Rules
Do not route the other signal or power trace under the engine board.
* RF: This pin receives signal of GPS analog via external active antenna. It has to be a controlled
impedance trace at 50ohm.
Do not place the RF traces close to the other signal path and not routing it on the top layer.
Keep the RF traces as short as possible.
* Antenna: Keep the active antenna on the top of your system and confirm the antenna radiation
pattern、axial ratio、power gain、noise figure、VSWR are correct when you Setup the antenna in your case.
GPS Passive (or Active) Antenna Specifications (Recommendation)
Frequency: 1575.42±2 MHz Axial Ratio: 3 dB Typical Output Impedance: 50 Polarization: RHCP Output VSWR: 1.5 Max.
Active option
Low Noise Amplifier:
Amplifier Gain: 18~22dB Typical Output VSWR: 2.0 Max. Noise Figure: 2.0 dB Max. Antenna Input Voltage: 2.85V Typical
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EB-3531
Version 1.2.1
Design Notes
VCC: This is the main power supply to the engine board. (3.3Vdc ± 5%). GND: Ground pin for the baseband circuit. RXA: This is the main channel for receiving software commands from SiRFdemo software or
from your proprietary software.
RXB: For user’s application (default null). TXA: This is the main channel for transmitting navigation and measurement data to a navigation
software or user written software. Output TTL level, 0V ~ 2.85V.
TXB: For user’s application (default null). RF_IN: This pin receives signal of GPS analog via external active antenna. It has to be a
controlled impedance trace at 50ohm. Do not have RF traces closed the other signal path and routing it on the top layer. Keep the RF traces as short as possible. VBAT: This is the battery backup power input for the SRAM and RTC when main power is removed. Typically, the current draw is 15uA. Without the external backup battery, the module/engine board will always execute a cold star after turning on. To achieve the faster start-up offered by a hot or warm start, a battery backup must be connected. The battery voltage should be between 2.0v and 3.6v.
From Vcc connect a 470 Ohm resistor in series with a 3.2v Zener diode to Ground. Then, connect the Rx
(NOTE: When not in use this pin must be kept “HIGH” for operation.
input to Zener’s cathode to pull the input “HIGH”.)
GPIO: User can use this I/O pin for special functions. (For example, control LED).
BOOTSEL: Set this pin to high for programming flash. VCC_RF: Provide Active Antenna Power 2.85V. ON_OFF: Edge triggered soft on/off request. It must be low for normal application. GPIO15: GPS status output. You can connect it to an LED.
Tracking: Fixing: Hi
RF_PWR_CTRL: RF power ON/OFF control. Hi: RF Power ON. Low: RF Power OFF.
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EB-3531
Version 1.2.1
Demo Kit Test Description
Connect J2 of the demo kit (Male) to J5 of the Test Board (Female) as the diagram below.
Pin Assignment
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J2
J3
EB-3531
Pin Signal Name Pin Signal Name
1 NC 2 VCC
3 NC 4 VCC
5 NC 6 NC
7 NC 8 NC
9 NC 10 GND
11 TXA 12 RXA
13 GND 14 TXB
15 RXB 16 GND
17 NC 18 GND
19 NC 20 NC
Pin Signal Name Pin Signal Name
Version 1.2.1
JP1: VBAT
1 TIMEMARK 2 VCC_RF
3 NC 4 GPIO15
5 GPIO0 6 GPIO14
7 GPIO1 8 GPIO13
9 RF_PWR 10 NC
11 NC 12 NC
13 NC 14 NC
15 NC 16 NC
17 NC 18 NC
19 NC 20 NC
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EB-3531
Test Software (GPSinfo)
1. Select COM Port & Baud Rate
2. Press Start GPS
Version 1.2.1
3. Software Commands
NMEA Output Command
GGA-Global Positioning System Fixed Data
Table B-2 contains the values for the following example: $GPGGA,161229.487,3723.2475,N,12158.3416,W,1,07,1.0,9.0,M,,,,0000*18
Table B-2 GGA Data Format
Name Example Units Description
Message ID $GPGGA GGA protocol header UTC Time 161229.487 hhmmss.sss Latitude 3723.2475 ddmm.mmmm N/S Indicator N N=north or S=south
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EB-3531
Longitude 12158.3416 dddmm.mmmm E/W Indicator W E=east or W=west Position Fix Indicator 1 See Table B-3 Satellites Used 07 Range 0 to 12 HDOP 1.0 Horizontal Dilution of Precision MSL Altitude1 9.0 meters Units M meters Geoid Separation1 meters 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
SiRF Technology Inc. does not support geoid corrections. Values are WGS84 ellipsoid heights.
Table B-3 Position Fix Indicator
Value Description
0 Fix not available or invalid 1 GPS SPS Mode, fix valid 2 Differential GPS, SPS Mode , fix valid 3 GPS PPS Mode, fix valid
GLL-Geographic Position-Latitude/Longitude
Table B-4 contains the values for the following example: $GPGLL,3723.2475,N,12158.3416,W,161229.487,A*2C
Table B-4 GLL Data Format
Name Example Units Description
Message ID $GPGLL GLL protocol header 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 UTC Position 161229.487 hhmmss.sss Status A A=data valid or V=data not valid Checksum *2C <CR><LF> End of message termination
GSA-GNSS DOP and Active Satellites
Version 1.2.1
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EB-3531
Table B-5 contains the values for the following example: $GPGSA,A,3,07,02,26,27,09,04,15,,,,,,1.8,1.0,1.5*33
Table B-5 GSA Data Format
Name Example Units Description
Message ID $GPGSA GSA protocol header
Mode1 A See Table B-6
Mode2 3 See Table B-7
Satellite Used1 07 Sv on Channel 1
Satellite Used1 02 Sv on Channel 2
.
Satellite Used1 Sv on Channel 12
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 B-6 Mode1
Value Description
M Manual-forced to operate in 2D or 3D mode
A 2D automatic-allowed to automatically switch 2D/3D
Table B-7 Mode 2
Value Description
1 Fix Not Available
2 2D
3 3D
GSV-GNSS Satellites in View
Table B-8 contains the values for the following example: $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
Table B-8 GSV Data Format
Version 1.2.1
Name Example Units Description
Message ID $GPGSV GSV protocol header Number of Messages1 2 Range 1 to 3 Message Number1 1 Range 1 to 3
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EB-3531
5
a
5
a
Satellites in View 07 Satellite ID 07 Channel 1(Range 1 to 32) Elevation 79 degrees Channel 1(Maximum90) Azimuth 048 degrees Channel 1(True, Range 0 to 3 SNR(C/No) 42 dBHz Range 0 to 99,null when not tr ……. ……. Satellite ID 27 Channel 4 (Range 1 to 32) Elevation 27 Degrees Channel 4(Maximum90) Azimuth 138 Degrees Channel 4(True, Range 0 to 3 SNR(C/No) 42 dBHz Range 0 to 99,null when not tr Checksum *71 <CR><LF> End of message termination
Depending on the number of satellites tracked multiple messages of GSV data may be required.
Version 1.2.1
RMC-Recommended Minimum Specific GNSS Data
Table B-9 contains the values for the following example: $GPRMC,161229.487,A,3723.2475,N,12158.3416,W,0.13,309.62,120598,,*10
Table B-9 RMC Data Format
Name Example Units Description
Message ID $GPRMC RMC protocol header UTC Time 161229.487 hhmmss.sss Status A A=data valid or V=data not valid 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 Speed Over Ground 0.13 knots Course Over Ground 309.62 degrees True Date 120598 ddmmyy Magnetic Variation2 degrees E=east or W=west Checksum *10 <CR><LF> End of message termination SiRF Technology Inc. does not support magnetic declination. All “course over ground” data are Geodetic WGS48 directions.
VTG-Course Over Ground and Ground Speed $GPVTG,309.62,T,,M,0.13,N,0.2,K*6E
Table B-9 VTG Data Format
Name Example Units Description
Message ID $GPVTG VTG protocol header
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EB-3531
Course 309.62 degrees Measured heading Reference T True Course degrees Measured heading Reference M Magnetic Speed 0.13 knots Measured horizontal speed Units N Knots Speed 0.2 Km/hr Measured horizontal speed Units K Kilometers per hour Checksum *6E <CR><LF> End of message termination
NMEA Input Command A.) Set Serial Port ID:100 Set PORTA parameters and protocol
Version 1.2.1
This command message is used to set the protocol (SiRF Binary, NMEA, or USER1) and/or
the communication parameters (baud, data bits, stop bits, parity). Generally, this command
is utilize to switch the GPS module back to SiRF Binary protocol mode, where an extensive
message commands are readily available. In example, whenever users are interested in
altering navigation parameters, a valid message sent and is receive by the recipient module,
the new parameters will be stored in battery backed SRAM and then the receiver will restart
using the saved parameters.
Format: $PSRF100,<protocol>,<baud>,<DataBits>,<StopBits>,<Parity>*CKSUM <CR><LF>
<protocol> 0=SiRF Binary, 1=NMEA, 4=USER1 <baud> 1200, 2400, 4800, 9600, 19200, 38400 <DataBits> 8,7. Note that SiRF protocol is only valid f8 Data bits <StopBits> 0,1 <Parity> 0=None, 1=Odd, 2=Even
Example 1: Switch to SiRF Binary protocol at 9600,8,N,1 $PSRF100,0,9600,8,1,0*0C<CR><LF> Example 2: Switch to User1 protocol at 38400,8,N,1 $PSRF100,4,38400,8,1,0*38<CR><LF>
**Checksum Field: The absolute value calculated by exclusive-OR the 8 data bits of each
character in the Sentence, between, but, excluding “$” and “*”. The hexadecimal value of the
most significant and least significant 4 bits of the result are converted to two ASCII characters
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EB-3531
Version 1.2.1
(0-9,A-F) for transmission. First, the most significant character is transmitted.
**<CR><LF> : Hex 0D 0A
B.) Navigation initialization ID:101 Parameters required for start
This command is used to initialize the GPS module for a “Warm” start, by providing real-time position
in X, Y, Z coordinates), clock offset, and time. This action enables the GPS receiver to search for the necessary satellite signals at the correct signal parameters. The newly acquired and stored satellite data will enable the receiver to acquire signals more quickly, and thus, generate a rapid navigational solution.
When a valid Navigation Initialization command is receive, the receiver will restart using the input
parameters as a basis for satellite selection and acquisition.
Format $PSRF101,<X>,<Y>,<Z>,<ClkOffset>,<TimeOfWeek>,<WeekNo>,<chnlCount>,<ResetCfg> *CKSUM<CR><LF>
<X> X coordinate position INT32
<Y> Y coordinate position INT32 <Z> Z coordinate position INT32 <ClkOffset> Clock offset of the receiver in Hz, Use 0 for last saved value if available.
If this is unavailable, a default value of 75000 for GSP1, 95000 for GSP 1/LX
is used. INT32 <TimeOf Week> GPS Time Of Week UINT32 <WeekNo> GPS Week Number UINT16 Week No and Time Of Week calculation from UTC time <chnlCount> Number of channels to use.1-12. If your CPU throughput is not high enough,
you could decrease needed throughput by reducing the number of active
channels UBYTE <ResetCfg> bit mask 0×01=Data Valid warm/hotstarts=1 0×02=clear ephemeris warm start=1 0×04=clear memory. Cold start=1 UBYTE
Example: Start using known position and time. $PSRF101,-2686700,-4304200,3851624,96000,497260,921,12,3*7F
C.) Set DGPS Port ID:102 Set PORT B parameters for DGPS input
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EB-3531
Version 1.2.1
This command is used to control Serial Port B, an input serial only port used to receive RTCM
differential corrections. Differential receivers may output corrections using different communication parameters. The default communication parameters for PORT B are set for 9600 Baud, 8data bits, 0 stop bits, and no parity. If a DGPS receiver is used which has different communication parameters, use this command to allow the receiver decode data correctly. When a valid message is received, the parameters are stored in a battery backed SRAM. Resulting, GPS receiver using the saved Parameters for restart.
Format: $PSRF102,<Baud>,<DataBits>,<StopBits>,<Parity>*CKSUM<CR><LF>
<baud> 1200,2400,4800,9600,19200,38400 <DataBits> 8 <StopBits> 0,1 <Parity> 0=None,Odd=1,Even=2
Example: Set DGPS Port to be 9600,8,N,1 $PSRF102,9600,8,1.0*12
D.) Query/Rate Control ID:103 Query standard NMEA message and/or set output rate
This command is used to control standard NMEA data output messages: GGA, GLL, GSA, GSV, RMC,
and VTG. Using this command message, standard NMEA message is polled once, or setup for periodic output. In addition, checksums may also be enable or disable contingent on receiving program requirements. NMEA message settings are stored in a battery-backed memory for each entry when the message is accepted.
Format: $PSRF103,<msg>,<mode>,<rate>,<cksumEnable>*CKSUM<CR><LF>
<msg> 0=GGA,1=GLL,2=GSA,3=GSV,4=RMC,5=VTG <mode> 0=SetRate,1=Query <rate> Output every <rate>seconds, off=0,max=255 <cksumEnable> 0=disable Checksum,1=Enable checksum for specified message
Example 1: Query the GGA message with checksum enabled $PSRF103,00,01,00,01*25
Example 2: Enable VTG message for a 1Hz constant output with checksum enabled $PSRF103,05,00,01,01*20
Example 3: Disable VTG message $PSRF103,05,00,00,01*21
E.) LLA Navigation initialization ID:104 Parameters required to start using Lat/Lon/Alt
This command is used to initialize the GPS module for a “Warm” start, providing real-time position
(Latitude, Longitude, Altitude coordinates), clock offset, and time. This action enables the GPS receiver to search for the necessary satellite signals at the correct signal parameters. The newly
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EB-3531
Version 1.2.1
acquired and stored satellite data will enable the receiver to acquire signals more quickly, and thus, generate a rapid navigational solution.
When a valid LLA Navigation Initialization command is receive, then the receiver will restart using the
input parameters as a basis for satellite selection and acquisition.
Format: $PSRF104,<Lat>,<Lon>,<Alt>,<ClkOffset>,<TimeOfWeek>,<WeekNo>, <ChannelCount>, <ResetCfg>*CKSUM<CR><LF>
<Lat> Latitude position, assumed positive north of equator and negative
south of equator float, possibly signed
<Lon> Longitude position, it is assumed positive east of Greenwich
and negative west of Greenwich Float, possibly signed
<Alt> Altitude position float, possibly signed
<ClkOffset> Clock Offset of the receiver in Hz, use 0 for last saved value if
available.
If this is unavailable, a default value of 75000 for GSP1, 95000 for GSP1/LX
is used. INT32 <TimeOfWeek> GPS Time Of Week UINT32 <WeekNo> GPS Week Number UINT16 <ChannelCount> Number of channels to use. 1-12 UBYTE <ResetCfg> bit mask 0×01=Data Valid warm/hot starts=1 0×02=clear ephemeris warm start=1 0×04=clear memory. Cold start=1 UBYTE Example: Start using known position and time. $PSRF104,37.3875111,-121.97232,0,96000,237759,922,12,3*37
F.) Development Data On/Off ID:105 Switch Development Data Messages On/Off Use this command to enable development debug information if you are having trouble in attaining
commands accepted. Invalid commands will generate debug information that should enable the user to determine the source of the command rejection. Common input rejection problems are associated to invalid checksum or parameter out of specified range. Note, this setting is not preserved across a module reset.
Format: $PSRF105,<debug>*CKSUM<CR><LF> <debug> 0=Off,1=On Example: Debug On $PSRF105,1*3E
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EB-3531
Example: Debug Off $PSRF105,0*3F
G). Select Datum ID:106 Selection of datum to be used for coordinate transformations
GPS receivers perform initial position and velocity calculations using an earth-centered earth-fixed
(ECEF) coordinate system. Results may be converted to an earth model (geoid) defined by the selected datum. The default datum is WGS 84 (World Geodetic System 1984) which provides a worldwide common grid system that may be translated into local coordinate systems or map Datum. (Local map Datum are a best fit to the local shape of the earth and not valid worldwide.)
Examples: Datum select TOKYO_MEAN $PSRF106,178*32
Name Example Units Description
Message ID $PSRF106 PSRF106 protocol header Datum 178 21= WGS84
178= Tokyo_Mean 179= Tokyo_Japan 180= Tokyo_Korea
181= Tpkyo_Okinawa Checksum *32 <CR><LF> End of message termination
Version 1.2.1
* * *
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