GlobalSat ET-318 User Guide

ET-318

Version 2.0

GPS Engine Board ET-318

Version 2.0

07/19/2007

Globalsat Technology Corporation Headquarters (Far East Century Park)

16F., No. 186, Jian-Yi Road, Chung-Ho City, Taipei Hsien 235, Taiwan

Tel: 886-2-8226-3799/ Fax: 886-2-8226-3899

E-mail : service@globalsat.com.tw

Website: www.globalsat.com.tw

Page 1 of 26

ET-318

Version 2.0

1. Product Information



Product Name: ET-318



Product Description:

ET-318 is a compact, high performance, and low power consumption GPS engine board. It uses SiRF

Star III chipset which can track up to 20 satellites at a time and perform fast TTFF in weak signal

environments. ET-318 is suitable for the following applications:

‧

Automotive navigation

‧

Personal positioning

‧

Fleet management

‧

Mobile phone navigation

‧

Marine navigation



Product Features:



SiRF star III high performance GPS Chipset



Very high sensitivity (Tracking Sensitivity: -159 dBm)



Extremely fast TTFF (Time To First Fix) at low signal level



Two serial ports



Built-in LNA



Compact size (15.2mm * 14 mm * 2.6mm) suitable for space-sensitive application



One size component, easy to mount on another PCB board



Support NMEA 0183 and SiRF binary protocol



Product Specifications

GPS Receiver

Chipset

Frequency L1, 1575.42 MHz

Code C/A Code

Protocol NMEA 0183 v2.2

SiRF GSC3f/LP

Default:GGA,GSA,GSV,RMC

Support:VTG,GLL,ZDA)

SiRF binary and NMEA Command

Available Baud Rate 4,800 to 57,600 bps adjustable

Channels 20

Page 2 of 26

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

Velocity: 0.1 m/s

Time: 1us synchronized to GPS time

ET-318

5 meters, 2D RMS, WAAS enabled

Version 2.0

Maximum Altitude

Maximum Velocity

Maximum Acceleration

Update Rate 1 Hz

DGPS WAAS, EGNOS, MSAS

Datum WGS-84

I/O Pins 2 serial ports

Type 17-pin stamp holes

Dimensions 15.2 mm * 14 mm * 2.6 mm

Power Supply

Backup Voltage

Power Consumption

＜ 18,000 meter

＜ 515 meter/second

＜ 4G

Interface

Physical Characteristic

DC Characteristics

3.3Vdc ± 5%

2.0 ~ 3.6Vdc ± 10%

Acquisition: 42mA Tracking: 25mA

Environmental Range

Humidity Range 5% to 95% non-condensing

Operation Temperature

Storage Temperature

-40℃ to 85℃

-40℃ to 125℃

Page 3 of 26

ET-318

Version 2.0

2. Technical Information



Block Diagram

Page 4 of 26



Module Pin Assignment:

ET-318

Version 2.0

1 GND G Analog Ground

2 RF_IN RF GPS Signal input

3 GND G Analog Ground

4 NRESET I Reset (Active low)

5 VCC_IN PWR DC Supply Voltage input

6 VBAT PWR Backup voltage supply

7 RXB I Serial port B

8 TXB O Serial port B

9 GND G Analog Ground

10 BOOTSEL Boot mode

11 TXA O Serial port A

12 RXA I Serial port A

13 GPIO1 I General –purpose I/O

14 GPIO14 I General –purpose I/O

15 TIMEMARK O One pulse per second

16 GPIO13 I General –purpose I/O

17 GPIO15 I General –purpose I/O

Signal Name

I/O

Description

Page 5 of 26

Definition of Pin assignment

ET-318

Version 2.0

VCC_IN

This is the main DC supply for a 3.3V +- 5% DC input power module board.

GND

GND provides the ground for digital part.

BOOTSEL

Set this pin to high for programming flash.

RXA

This is the main receiver channel and is used to receive software commands to the board from SIRFdemo software or from user written software. PS: Pull up if not used.

RXB

This is the auxiliary receiving channel and is used to input differential corrections to the board to enable DGPS navigation. PS: Pull up if not used.

TXA

This is the main transmitting channel and is used to output navigation and measurement data to SiRFdemo or user written software.

TXB

For user’s application (not currently used).

RF_IN

This pin receiver signal of GPS analog .due to the RF characteristics of the signal the design has to certain criteria. The line on the PCB from the antenna(or antenna connector) has to be a controlled microstrip line at 50Ω.

Backup battery (V_BAT)

This is the battery backup input that powers the SRAM and RTC when main power is removed. Typical current draw is 15uA. Without an external backup battery, the module/engine board will execute a cold star after every turn 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 5.0v.

TIMEMARK

This pin provides one pulse-per-second output from the board, which is synchronized to GPS time. This is not available in Trickle Power mode.

GPIO Functions

Several I/Os are connected to the digital interface connector for custom applications.

Page 6 of 26



Application Circuit

ET-318

Version 2.0

GPS Active Antenna Specification(Recommendation)

Frequency: 1575.42+2 MHz

Axial Ratio: 3 dB Typical

output Impedance: 50Ω

Polarization: RHCP

Amplifier Gain :18~22dB Typical

Output VSWR: 2.0 Max.

Noise Figure: 2.0 dB Max

Page 7 of 26



Dimensions

ET-318

Version 2.0



Recommend Layout PAD

Page 8 of 26

ET-318

Version 2.0

Application Circuit

1.

J1_I-PEX connect

External antenna

1 2

50 Ohm Micro strip line

RF Switch

2

1

GPS_3V3

C1

1 2

1U

24-20003-12030N

C2

0.1U

1 2

ET318 Application guideline

VCC-R F

12

L1

33N

50 Ohm Micro strip line

1

D5

RB521S

1 2

12

R1 270R

BATTERY

BT1

C3

100p

12

D6

RB512S

RESET

RXB

TXB

1

2

3

4

5

6

7

8

U1

GND

RF_I N

GND

NRESET

VCC_I N

VBAT

RXB

TXB

GPS

GPIO15

GPIO13

TIMEMARK

GPIO14

BOOTSEL

GPIO1

RXA

TXA

GND

17

16

TIMEMAR K

15

14

13

12

11

10

9

GPIO15

GPIO13

GPIO14

GPIO1

RXA

TXA

Bootsel

L4 BLM18AG121SN1D

L3 BLM18AG121SN1D

12

TXD 1

RXD1

2.

GPS_3V3

1 2

VCC-R F

J1_I-PEX connec t

External antenna

1 2

50 Ohm Micro strip line

RF Switch Circuit

C1

1U

C2

0.1U

1 2

D5

RB521S

12

L1

1 2

12

33N

R1 270R

BATTERY

BT1

C3

100p

RB512S

12

RESET

RXB

D6

TXB

1

2

3

4

5

6

7

8

U1

GND

RF_I N

GND

NRESET

VCC_I N

VBAT

RXB

TXB

GPS

GPIO15

GPIO13

TIMEMAR K

GPIO14

GPIO1

RXA

TXA

BOOTSEL

GND

17

16

TIMEMARK

15

14

13

12

11

10

9

GPIO15

GPIO13

GPIO14

GPIO1

RXA

TXA

Bootsel

L4 BLM18AG121SN1D

L3 BLM18AG121SN1D

12

TXD 1

RXD1

Page 9 of 26

3.GPS Power

VCC

GPS-power

ET-318

GPS_3V3

Version 2.0

12

C4

+

22uF/10V

U1

1

VINNCVOUT

4

XC6209F332MRN

CE

GND

5 3 2

R2 100K

1 2

12

C5

1uF /2 5V

L2

GMLB-100505-0020P-N8

12

C6

470pF

GPIO

C7

10uF/16V

12

+

C8

0.1uF

Layout Rule

.Do not routing 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 has to be a

controlled impedance at 50 ohm .

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

* 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 you case.

GPS Passive (or Active )Antenna Specification(Recommendation)

Frequency: 1575.42±2 MHz

Axial Ratio: 3 dB Typical

output Impedance: 50Ω

Polarization: RHCP

Output VSWR: 1.5 Max.

Active option

Low Noise Amplifter:

Amplifier Gain :18~22dB Typical

Output VSWR: 2.0 Max.

Noise Figure: 2.0 dB Max.

Page 10 of 26

ET-318

Definition of Pin assignment

VCC_IN

This is the main DC supply for a 3.3V ± 5% DC input power module board.

GND

GND provides the ground for digital part.

BOOTSEL

Set this pin to high for programming flash.

RXA

This is the main receive channel for receiving software commands to the engine board from

SiRFdemo software or from user written software.

Option to add EMI solutions

Version 2.0

RXB

This is the auxiliary receiving channel and is used to input differential corrections to the board to

enable DGPS navigation.

PS: Pull up if not used.

TXA

This is the main transmits channel for outputting navigation and measurement data to user’s

navigation software or user written software.

Output TTL level, 0V ~ 2.85V

Option to add EMI solutions

TXB

For user’s application (not currently used).

RF_IN

This pin receives signal of GPS analog via external active antenna .It has to be a has to be a

controlled impedance at 50 ohm .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.

TIMEMARK

This pin provides one pulse-per-second output from the board, which is synchronized to GPS time.

This is not available in Trickle Power mode.

Page 11 of 26

ET-318

Backup battery (V_BAT)

This is the battery backup input that powers the SRAM and RTC when main power is removed.

Typical current draw is 15uA. Without an external backup battery, the module/engine board will

execute a cold star after every turn 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 5.0v.

GPIO Functions

Several I/Os are connected to the digital interface connector for custom applications.

(For example, on/off LED)

Other

VCC_RF:

This is providing bias voltage for active antenna via a inductance.

Version 2.0

Page 12 of 26

ET-318

ET-318 Demo Kit Test Description

Test Board Connection ET-318 Demo Kit:

Demo Kit J2 (Male) Connection Test Board J5 (Female)

Definition of Pin assignment

Version 2.0

J2: J3:

Pin Signal Name Pin Signal Name Pin Signal Name Pin Signal Name

1 VCC 2 VCC 1 GPIO15 2 NC

3 NC 4 NC 3 GPIO13 4 NC

5 NC 6 NC 5 TIMEMARK 6 NC

7 NC 8 NC 7 GPIO14 8 NC

9 NC 10

GND 9 GPIO1 10

Page 13 of 26

NC

ET-318

Version 2.0

11

13

15

17

19

TXA 12

GND 14

RXB 16

NC 18

NC 20

RXA 11

TXB 13

GND 15

GND 17

NC 19

JP1: VBAT

JP2: Active Antenna VCC

JP3: Bootsel

Test Software GPSinfo:

1. Select COM Port & Baud Rate

2. Press Start GPS

RESET 12

NC 14

NC 16

NC 18

NC 20

NC

Page 14 of 26

SOFTWARE COMMAND

Name

Example

Units

Description

Message ID

$GPGGA

GGA protocol he

ader

UTC Time

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 Table B

-3

Satellites Used

07 Range 0 to 12

HDO

P 1.0

Horizontal Dilution of Precision

MSL Altitude

9.0 meters

Units

M

meters

Geoid Separation

meters

Units

M

meters

Age of Diff. Corr.

second

Null fields when DGPS is not used

Diff. Ref. Station ID

0000

Checksum

*18

End of

message termination

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

NMEA Output Command

GGA-Global Positioning System Fixed Data

ET-318

Version 2.0

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

1

Table B-2 GGA Data Format

SiRF Technology Inc. does not support geoid corrections. Values are WGS84 ellipsoid heights.

Table B-3 Position Fix Indicator

GLL-Geographic Position-Latitude/Longitude

$GPGLL,3723.2475,N,12158.3416,W,161229.487,A*2C

Table B-4 contains the values for the following example:

Page 15 of 26

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

End of message termination

Table B-4 GLL Data Format

GSA-GNSS DOP and Active Satellites

$GPGSA,A,3,07,02,26,27,09,04,15,,,,,,1.8,1.0,1.5*33

Table B-5 GSA Data Format

Table B-5 contains the values for the following example:

Name Example Units Description Message ID $GPGSA 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

Table B-6 Mode1

Value

M Manual-forced to operate in 2D or 3D mode A 2Dautomatic-allowed to automatically switch 2D/3D

Table B-7 Mode 2

Value

1 Fix Not Available 2 2D 3 3D

GSV-GNSS Satellites in View

1. Satellite used in solution.

Description

GSA protocol header

ET-318

Version 2.0

Table B-8 contains the values for the following example:

Page 16 of 26

Name

Example

Description

Message ID

$GPGSV

GSV protocol header

Number of Messages

2 Range 1 to 3

Message Number

1 Range 1 to 3

Satellites in View

07

Satellite ID

07 Channel 1(Range 1 to 32)

Elevation

79

degree

s Channel 1(Maximum90)

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(Maximum90)

Azimuth

138 Degrees

Chann

el 4(True, Range 0 to 359)

SNR(C/No)

42

dBHz

Range 0 to 99,null when not tracking

Checksum

*71

End of message termination

Name

Example

Units

Descript

ion

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 Variation

degrees

E=east or W=west

Checksum

*10

End of message termination

$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

1

ET-318

Version 2.0

Depending on the number of satellites tracked multiple messages of GSV data may be required.

$GPRMC,161229.487,A,3723.2475,N,12158.3416,W,0.13,309.62,120598,,*10

Table B-10 RMC Data Format

RMC-Recommended Minimum Specific GNSS Data

Table B-10 contains the values for the following example:

2

SiRF Technology Inc. does not support magnetic declination. All “course over ground” data are

geodetic WGS48 directions.

Page 17 of 26

Name

Example

Units

Description

Message ID

$GPVTG

VTG protocol header

Course

309.62

degrees

Measur

ed 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

End of

message termination

ET-318

VTG-Course Over Ground and Ground Speed

$GPVTG,309.62,T,,M,0.13,N,0.2,K*6E

Version 2.0

2.2 NMEA Input Command

A)

. Set Serial Port ID:100 Set PORTA parameters and protocol

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 would be used to

switch the module back to SiRF Binary protocol mode where a more extensive command message set is

available. For example,to change navigation parameters. When a valid message is received,the 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

<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

Page 18 of 26

<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

convertted to two ASCII characters (0-9,A-F) for transmission. The most

significant character is transmitted first.

**<CR><LF> : Hex 0D 0A

ET-318

Version 2.0

B). Navigation lnitialization ID：：：：101 Parameters required for start

This command is used to initialize the module for a warm start, by providing current position （in X, Y, Z coordinates）,clock offset, and time. This enables the receiver to search for the correct satellite signals at

the correct signal parameters. Correct initialization parameters will enable the receiver to acquire signals

more quickly, and thus, produce a faster navigational solution.

When a valid Navigation Initialization command is received, 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

Page 19 of 26

<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 will be used.

INT32

<TimeOf Week> GPS Time Of Week

UINT32

<WeekNo> GPS Week Number

UINT16

ET-318

Version 2.0

（ 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

Page 20 of 26

ET-318

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

C). Set DGPS Port ID:102 Set PORT B parameters for DGPS inputC). Set DGPS Port ID:102 Set PORT B parameters for DGPS input

This command is used to control Serial Port B that is an input only serial port

used to receive

RTCM differential corrections.

Differential receivers may output corrections using different

Version 2.0

communication parameters. The default

communication parameters for PORT B are 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 to

correctly decode the data. When a valid message is received, the parameters will be stored in

battery backed SRAM and then the receiver will restart using the saved parameters.

Format:

＄PSRF102,<Baud>,<DataBits>,<StopBits>,<Parity>*CKSUM<CR><LF>

<baud> 1200,2400,4800,9600,19200,38400

<DataBits> 8

<StopBits> 0,1

Page 21 of 26

ET-318

Version 2.0

<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

D). Query/Rate Control ID:103 Query standard NMEA message and/or set output rateD). Query/Rate Control ID:103 Query standard NMEA message and/or set output rate

This command is used to control the output of standard NMEA message GGA, GLL, GSA,

GSV

RMC, VTG. Using this command message, standard NMEA message may be polled once,

or setup for periodic output. Checksums may also be enabled or disabled depending

on the needs of the receiving program. NMEA message settings are saved in 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

Page 22 of 26

ET-318

Version 2.0

＄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 lnitialization ID:104 Parameters required to start using Lat/Lon/Alt

E). LLA Navigation lnitialization ID:104 Parameters required to start using Lat/Lon/Alt E). LLA Navigation lnitialization ID:104 Parameters required to start using Lat/Lon/Alt

This command is used to initialize the module for a warm start, by providing current position (in

Latitude, Longitude, Altitude coordinates), clock offset, and time. This enables the receiver

to search for the correct satellite signals at the correct signal parameters. Correct initialization

parameters will enable the receiver to acquire signals more quickly, and thus, will produce a

faster navigational soution.

When a valid LLANavigationInitialization command is received,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

Page 23 of 26

ET-318

Version 2.0

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

will be 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

Page 24 of 26

ET-318

Version 2.0

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

F). Development Data On/Off ID:105 Switch Development Data Messages On/Off 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 getting

commands accepted. Invalid commands will generate debug information that should

enable the user to determine the source of the command rejection. Common reasons for

input command rejection are invalid checksum or parameter out of specified range. 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

Example: Debug Off ＄PSRF105,0*3F

GGGG).

). Select Datum

Select Datum ID:10

). ).

Select DatumSelect Datum

Transformations

TransformationsTransformations

ID:106666

ID:10 ID:10

Selection of datum to be used for coordinate

Selection of datum to be used for coordinateSelection of datum to be used for coordinate

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

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worldwide common grid system that may be translated into local coordinate systems or map datums.

(Local map datums are a best fit to the local shape of the earth and not valid worldwide.)

Examples:

Datum select TOKYO_MEAN

$PSRF106,178*32

ET-318

Version 2.0

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