Rikaline GPS Receiver GPS 20 User Guide

Rikaline GPS-20  
GPS Engine Board  
SiRF Star II  
V1.0 Aug 09, 2002  
User’s Guide  
Rikaline Marketing Corp.  
5F-1, 125, RooseveltRd., Sec. 5, Taipei 116, Taiwan, R.O.C.  
Phone: +886-2-2934-5456 Fax: +886-2-2934-4373  
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1. Introduction  
1.1 Overview  
The Rikaline GPS-20 GPS Engine Board is a total solution GPS receiver, designed based on SiRF Star  
II Architecture and pin to pin compatible with SiRF Start I engine board for replacing the system existing in  
the market using SiRF Start I. This positioning application meets strict needs such as car navigation,  
mapping, surveying, security, agriculture and so on. Only clear view of sky and certain power supply are  
necessary to the unit. It communicates with other electronic utilities via compatible dual-channel through  
RS-232 or TTL and saves critical satellite data by built–in backup memory. With low power consumption, the  
GPS-20 tracks up to 12 satellites at a time, re-acquires satellite signals in 100 ms and updates position data  
every second. Trickle-Power allows the unit operates a fraction of the time and Push-to-Fix permits user to  
have a quick position fix even though the receiver usually stays off.  
1.2 Features  
The GPS-20 provides a host of features that make it easy for integration and use.  
1. SiRF Star II chipset with embedded ARM7TDMI CPU available for customized applications in  
firmware.  
2. High performance receiver tracks up to 12 satellites while providing first fast fix and low power  
consumption.  
3. Differential capability utilizes real-time RTCM corrections producing 1-5 meter position accuracy.  
4. Compact design ideal for applications with minimal space.  
5. A rechargeable battery sustains internal clock and memory. The battery is recharged during normal  
operation.  
6. User initialization is not required.  
7. Dual communication channels and user selectable baud rates allow maximum interface capability and  
flexibility.  
8. Optional communication levels, RS-232 and TTL meet ordinary application and new fashions of  
connecting PDA with TTL or RS-232 output.  
9. FLASH based program memory: New software revisions upgradeable through serial interface.  
10. Built-in WAAS and EGNOS demodulator.  
1.3 Technical specifications  
1.3.1 Physical Characteristics  
Dimension: 71.1(L) x 40.6(W) x 14.4(H) mm  
2.80"(L) x 1.60"(W) x 0.57"(H).  
Weight: 25g  
1.3.2 Environmental Characteristics  
1) Operating temperature: -40oC to +85oC  
2) Storage temperature: -55oC to +100oC.  
-45oC to +80oC with battery  
1.3.3 Electrical Characteristics  
1.3.3.1 General:  
1) Frequency: L1, 1,575.42MHz  
2) C/A Code:  
3) Channels:  
1.023MHz Chip Rate  
12  
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1.3.3.2 Power  
GPS-20 5V Version GPS-20 3.3V Version  
TTL  
TTL  
Main Power  
+5VDC±5%  
3.3VDC±10%  
170mA Typical  
+2.5V to 3.3V  
10µA Typical  
230hr (9.6 days)  
Supply Current  
Backup Power  
Backup Current  
Packup Period  
170mA Typical  
+2.5V to 3.3V  
10µA Typical  
230hr (9.6 days)  
1.3.3.3 Datum  
WGS 84  
1.3.4 Performance  
1.3.4.1 Acquisition  
1) Tracks up to 12 satellites.  
2) Update rate: 1 second.  
3) Acquisition time  
Reacquisition 0.1 sec., averaged  
Snap Start  
Hot start  
3
8
sec, averaged  
sec., averaged  
Warm start  
Cold start  
38 sec., averaged  
45 sec., averaged  
1.3.4.2 Position Aaccuracy: (Non Differential GPS)  
Position  
Velocity  
Time  
5-25 meter CEP without SA  
0.1 meters/second, without SA  
1
microsecond synchronized GPS time  
1.3.4.3 DGPS Accuracy (Differential GPS)  
Position  
Velocity  
1 to 5 meter, typical  
0.05 meters/second, typical  
1.3.4.4 Dynamic Conditions  
Altitude  
Velocity  
Acceleration  
Jerk  
18,000 meters (60,000 feet) max  
515 meters / second (1,000 knots) max  
4 G, max  
20  
meters/second3 , max  
1.3.4.5 1PPS Pulse  
Level  
TTL  
Pulse Duration 100ms  
Time Reference at the pulse positive edge  
Measurements Aligned to GPS second, ± 1 microsecond  
1.3.5 Interfaces  
1.3.5.1 Interface  
Two full duplex serial communication, RS-232 or TTL compatible level, with user selectable baud rate  
(4800-Default, 9600, 19200, 38400).  
1.3.5.2 Protocol Message  
SiRF Binary – Position, Velocity, Altitude, Status and Control  
NMEA 0183 Version 2.2 ASCII output -- GGA, GLL, GSA, GSV, RMC, ZDA and VTG.  
4
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1.3.5.3 DGPS Protocol  
Real-time Differential Correction input (RTCM SC-104 version 2.00 message types 1, 5 and 9).  
2. Operational characteristics  
2.1 Initialization  
As soon as the initial self-test is complete, the GPS-20 begins the process of satellite acquisition and  
tracking automatically. Under normal circumstances, it takes approximately 45 seconds to achieve a position  
fix, 38 seconds if ephemeris data is known. After a position fix has been calculated, information about valid  
position, velocity and time is transmitted over the output channel.  
The GPS-20 utilizes initial data, such as last stored position, date, time and satellite orbital data, to  
achieve maximum acquisition performance. If significant inaccuracy exists in the initial data, or the orbital  
data is obsolete, it may take more time to achieve a navigation solution. The GPS-20 Auto-locate feature is  
capable of automatically determining a navigation solution without intervention from the host system.  
However, acquisition performance can be improved when the host system initializes the GPS-20 in the  
following situation:  
1) Moving further than 500 kilometers.  
2) Failure of data storage due to the inactive internal memory battery.  
2.2 Navigation  
After the acquisition process is complete, the GPS-20 sends valid navigation information over  
output channels. These data include:  
1) Latitude/longitude/altitude  
2) Velocity  
3) Date/time  
4) Error estimates  
5) Satellite and receiver status  
The GPS-20 sets the default of auto-searching for real-time differential corrections in RTCM SC-104  
standard format, with the message types 1, 5, or 9. It accomplishes the satellite data to generate a differential  
(DGPS) solution. The host system, at its option, may also command the GPS-20 to output a position  
whenever a differential solution is available.  
5
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3. Hardware interface  
3.1 Connectors  
3.1.1 Antenna Connector  
MCX, RSMA  
3.1.2 Interface Connector  
20-Pin and 10-Pin straight header, 2mm pitch  
3.2 Pin Assignment of Connector  
Table 1-1 Pin list of the 20-Pin Digital Interface Connector (CN1)  
Pin Number  
Name  
Description  
1
2
ANT_PWR Antenna DC Voltage  
VCC_5V  
BAT  
+5 DC Power Input  
Backup Battery  
3
4
VCC_3V  
PBRES  
GPIOA  
GPIOB  
GPIOC  
GPIOD  
GND  
+3.3V DC Power Input  
5
Push Button Reset Input. Active Low  
SW dependent functions (note 1)  
SW dependent functions (note 1)  
SW dependent functions (note 1)  
SW dependent functions (note 1)  
Ground  
6
7
8
9
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
20  
TXA  
Serial Data Output A  
Serial Data Input A  
RXA  
GND  
Ground  
TXB  
Serial Data Output B  
Serial Data Input B  
RXB  
GND  
Ground  
BOOTSEL  
GND  
Booting Mode Select  
Ground  
TIMEMARK 1PPS Time Mark Output  
ALT/GPIOE Alternative output (Reserved)  
Table1-2Pinlistofthe10-PinDigitalInterfaceConnector(JP1)  
Pin Number  
Name  
Description  
1
2
GPIOF  
JTDI  
SW dependent functions (note 1)  
JTAG software debug function  
SW dependent functions (note 1)  
JTAG software debug function  
SW dependent functions (note 1)  
JTAG software debug function  
SW dependent functions (note 1)  
JTAG software debug function  
JTAG software debug function  
Ground  
3
GPIOG  
JTMS  
GPIOH  
JTCK  
GPIOI  
JTDO  
JTRST  
GND  
4
5
6
7
8
9
10  
Note: 1) Pulled high (VCC/VDD) through on-board 100K Ohm resister.  
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2) Pulled low (GND) through on-board 100K Ohm resister.  
3.2.1 VCC_5V (+5V DC Power Input)  
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This is the main DC power supply for a +5V-powered board. (Required for the GPS-20 5V version)  
3.2.2 VCC_3V (+3.3V DC Power Input)  
This is the main DC power supply for a +3.3V-powered board. (Required for 3.3V version)  
3.2.3 ANT_PWR  
DC voltage for an active antenna. This voltage is not required for operation with a passive antenna.  
The antenna power may be supplied through the interface connector (CN1). The current limiting  
(<200mA) should be supplied externally.  
3.2.4 GND  
GND provides the ground for the board. Connect all grounds.  
3.2.5 Serial Data: RXA, RXB, TXA and TXB  
The board supports two full duplex serial channels. All support variable baud rates, and all can be  
controlled from the appropriate screens in GPS Monitor software. You can directly communicate with  
a PC serial port.TTL level should be turned to RS-232 level)  
3.2.6 RXA  
This is the main receiving channel and is used to receive software commands to the board from GPS  
Monitor software or from user written software.  
3.2.7 RXB  
This is the auxiliary receiving channel and is used to input differential corrections to the board to  
enable DGPS navigation.  
3.2.8 TXA  
This is the main transmitting channel and is used to output navigation and measurement data to GPS  
Monitor or user written software.  
3.2.9 TXB  
For user’s application  
3.2.10 PBRES  
This pin provides an active-low reset input to the board. It causes the board to reset and start  
searching for satellites. PB Reset is an optional input and, if not utilized, it may be left open.  
3.2.11 Time mark  
This pin provides 1 pulse per second output from the board, which is synchronized to within 1  
microsecond of GPS time. The output is a TTL positive level signal.  
3.2.12 Battery (BAT)  
This is the battery backup supply that powers the SRAM and RTC when main power is off. Typical  
current draw is 10 µA.  
Without an external backup battery or supercap, the board will execute a cold start after every turn  
7
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on. To achieve the faster start-up offered by a hot start or warm start, either a battery backup input  
must be connected or a recharge battery installed  
.
Table 1-3 Backup Battery Voltage Range  
Board  
MIN  
MAX  
GPS-20  
2.5  
3.3  
With a 3.3V Lithium-Ion (2.3mAh) rechargeable .To maximize battery lifetime (3~5 years), the battery  
voltage should not exceed 3.3V.  
3.2.13 GPIO Functions  
Several I/Os of CPU are connected to the digital interface connector for consumer applications and  
are labeled GPIOA to GPIOI.  
3.2.14 JTAG Functions  
The JTAG interface provides a standard development/debugging interface. A simple header connects  
to a variety of the off-the-shelf emulators to provide single-step, trap and access to all the internal  
registers of the GSP2e.  
3.3 TricklePowerTM Description  
The GPS-20 design includes all the functionality necessary to implement the SiRF TricklePower  
mode of operation. In this mode, the lowest average power dissipation is achieved by powering down  
the board (after a position is determined) in such a manner that when it is turned back on it can  
recomputed a position fix in the shortest amount of time. Standard TricklePower operates in three  
states  
3.3.1 Tracking State  
In this state, the board is fully powered, tracking satellites, and gathering data.  
3.3.2 CPU State  
In this mode, the GRF2i has been turned off which removes the clock to the GSP2e. Without a clock,  
the GSP2e is effectively powered down (although the RTC keeps running). The CPU would switch to  
ECLK and kept running to process the GPS data until a position fix is determined and the result has  
been transmitted by the serial communication interface.  
3.3.3 Trickle State  
In this state, the CPU is in a low power standby state and the receiver clocks are off with only the  
RTC clock active. After a set amount of time, the RTC generates an NMI signal to wake up the  
ARM-7 microprocessor and reset the receiver back to tracking state.  
The default time for each TricklePower mode and the approximate current consumed (in each mode)  
is shown in Table 1-4. For example, the TricklePower duty cycle (20%), the average receiver power  
dissipation is approximately 165mW (60mA @ 3.3V) while maintaining one-second update rate.  
Table 1-4 TricklePowerTM Power Consumption  
+5V  
Current  
mA  
+3.3V  
Current  
mA  
Time  
Msec  
Mode  
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Tracking  
CPU  
220  
360  
420  
170  
33  
160  
29  
Trickle  
0.55  
0.55  
Note: Table 1-4 does not include the external antenna power, which must be controlled from the system  
power supply.  
3.4 Push-to-Fix Description  
The purpose of Push-to-Fix mode is to support applications where a position fix is only required when  
requested by the user (or the application). To support this, the board is left in the Trikle state until  
commanded to generate a fix.  
3.4.1 Power-on State  
In this state, the receiver calculates the position once, collects the ephemeris, and calibrates the RTC  
before going back to the Trickle State.  
3.4.2 Trickle State  
In this state only the RTC is running. The supply current is typically <500uA, which includes the  
standby current of the GSP2e and CPU.  
There are three events that can happen which effectively return the CPU to normal operation:  
3.4.3 Power-on  
If power is removed, then re-applied to the board a reset signal is generated by the CPU supervisor.  
After the reset has been removed, the CPU will start up, get a fix and return to Trickle State. This  
typically takes 2 to 6 seconds.  
3.4.4 Ephemeris Collection  
Every 30 minutes the GSP2e WAKEUP signal is activated, wake up the CPU to calculate a fix, collect  
a new ephemeris, calibrate the RTC and then go to the Trickle State.  
3.4.5 User Requested Fix  
With each user request of a fix, the CPU will wake up by toggling PBRES low (pin 5 of the digital  
interface connector). The CPU is restarted and (following a Snap Start) a fix is calculated. Before  
going back to Trickle State, the CPU will check the ephemeris and the RTC calibration.  
Note – The CPU will restart ~ 200-600 mSec after the PBRES input is brought high.  
3.5 SRAM DATA BACKUP Description  
SiRFchiphasaninternal1M bSRAM forGPStaskandOSkernel;besides,wehaveaddedanexternal4M b(Canbe  
expandedto8M b)foruserstoringcodes.  
9
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3.6 Mechanical Drawing  
3.6.1 Top View  
3.6.2 Lateral View  
3.6.3 Connector  
R
T
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4. Software Interface  
4.1 NMEA Transmitted Messages  
The GPS-20 supported by SiRF Technology Inc. also outputs data in NMEA-0183 format as defined by  
the National Marine Electronics Association (NMEA), Standard.  
The default communication parameters for NMEA output are 4800 baud, 8 data bits, stop bit, and no  
parity.  
Table 4-1 NMEA-0183 Output Messages  
NMEA Record  
Description  
Global positioning system fixed data  
GPGGA  
GPGLL  
Geographic position- latitude/longitude  
GNSS DOP and active satellites  
GNSS satellites in view  
Recommended minimum specific GNSS data  
Course over ground and ground speed  
GPGSA  
GPGSV  
GPRMC  
GPVTG  
4.1.1 Global Positioning System Fix Data (GGA)  
Table 5-2 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 4-2 GGA Data Format  
Name  
Message ID  
Example  
$GPGGA  
Units  
Description  
GGA protocol header  
UTC Time  
161229.487  
Hhmmss.sss  
Latitude  
3723.2475  
ddmm.mmmm  
N/S Indicator  
Longitude  
N
N=north or S=south  
dddmm.mmmm  
12158.3416  
E/W Indicator  
Position Fix Indicator  
Satellites Used  
HDOP  
MSL Altitude  
Units  
Geoid Separation  
Units  
Age of Diff. Corr.  
Diff. Ref. Station ID  
Checksum  
W
1
07  
1.0  
9.0  
M
E=east or W=west  
See Table 5-3  
Range 0 to 12  
Horizontal Dilution of Precision  
Meters  
Meters  
Meters  
Meters  
second  
M
Null fields when DGPS is not used  
End of message termination  
Description  
0000  
*18  
<CR> <LF>  
Table 4-3 Position Fix Indicator  
Value  
0
1
2
3
0 Fix not available or invalid  
GPS SPS Mode, fix valid  
Differential GPS, SPS Mode, fix valid  
GPS PPS Mode, fix valid  
11  
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4.1.2 Geographic Position with Latitude/Longitude (GLL)  
Table 4-4 contains the values for the following example:  
$GPGLL,3723.2475,N,12158.3416,W,161229.487,A*2C  
Table 4-4 GLL Data Format  
Name  
Message ID  
Latitude  
N/S Indicator  
Longitude  
E/W Indicator  
UTC Position  
Status  
Example  
$GPGLL  
3723.2475  
N
12158.3416  
W
Units  
Description  
GLL protocol header  
ddmm.mmmm  
N=north or S=south  
dddmm.mmmm  
E=east or W=west  
hhmmss.sss  
161229.487  
A
A=data valid or V=data not valid  
Checksum  
<CR> <LF>  
*2C  
End of message termination  
4.1.3 GNSS DOP and Active Satellites (GSA)  
Table 4-5 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 4-5 GSA Data Format  
Name  
Message ID  
Mode 1  
Example  
$GPGSA  
Units  
Description  
GSA protocol header  
A
3
See Table 5-6  
See Table 5-7  
Mode 2  
Satellite Used (1)  
Satellite Used (1)  
……  
07  
02  
Sv on Channel 1  
Sv on Channel 2  
….  
Satellite Used  
PDOP  
HDOP  
VDOP  
Checksum  
<CR> <LF>  
Sv on Channel 12  
Position Dilution of Precision  
Horizontal Dilution of Precision  
Vertical Dilution of Precision  
1.8  
1.0  
1.5  
*33  
End of message termination  
(1) Satellite used in solution.  
Table 4-6 Mode 1  
Value  
Description  
M
A
Manual—forced to operate in 2D or 3D mode  
2D Automatic—allowed to automatically switch 2D/3D  
Table 4-7 Mode 2  
Value  
Description  
1
2
3
Fix Not Available  
2D  
3D  
4.1.4 GNSS Satellites in View (GSV)  
Table 4-8 contains the values for the following example:  
12  
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$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 4-8 GSV Data Format  
Name  
Message ID  
Example  
$GPGSV  
2
Units  
Description  
GSV protocol header  
Range 1 to 3  
Range 1 to 3  
Range 1 to 12  
Number of Messages  
Message Number  
Satellites in View  
Satellite ID  
Elevation  
1
07  
07  
79  
Channel 1 (Range 1 to 32)  
degrees Channel 1 (Maximum 90)  
Azimuth  
SNR (C/No)  
....  
048  
42  
....  
degrees Channel 1 (True, Range 0 to 359)  
dBHz Range 0 to 99, null when not tracking  
Satellite ID  
Elevation  
27  
27  
Channel 4 (Range 1 to 32)  
degrees Channel 4 (Maximum 90)  
Azimuth  
138  
42  
*71  
degrees Channel 4 (True, Range 0 to 359)  
dBHz Range 0 to 99, null when not tracking  
SNR (C/No)  
Checksum  
<CR> <LF>  
End of message termination  
NOTE: Items <4>,<5>,<6> and <7> repeat for each satellite in view to a maximum of four (4) satellites per  
sentence. Additional satellites in view information must be sent in subsequent sentences. These fields will be  
null if unused.  
4.1.5 Recommended Minimum Specific GNSS Data (RMC)  
Table 4-9 contains the values for the following example:  
$GPRMC,161229.487,A,3723.2475,N,12158.3416,W,0.13,309.62,120598, ,*10  
Table 4-9 RMC Data Format  
Name  
Message ID  
UTC Time  
Example  
$GPRMC  
161229.487  
A
3723.2475  
N
12158.3416  
W
0.13  
309.62  
120598  
Units  
Description  
RMC protocol header  
hhmmss.sss  
Status  
Latitude  
A=data valid or V=data not valid  
ddmm.mmmm  
N=north or S=south  
dddmm.mmmm  
N/S Indicator  
Longitude  
E/W Indicator  
Speed Over Ground  
Course Over Ground  
Date  
E=east or W=west  
Knots  
Degrees True  
ddmmyy  
Degrees E=east or W=west  
Magnetic Variation (1)  
Checksum  
*10  
<CR> <LF>  
End of message termination  
(1) SiRF Technology Inc. does not support magnetic declination. All “course over ground” data are  
geodetic WGS84 directions.  
4.1.6 Course Over Ground and Ground Speed  
Table 4-10 contains the values for the following example:  
$GPVTG,309.62,T, ,M,0.13,N,0.2,K*6E  
Table 4-10 VTG Data Format  
13  
Rikaline Marketing Corp.  
5F-1, 125, Roosevelt Road, Sec. 5, Taipei, Taiwan 116  
Tel: ++886 2 2934 5456 Fax: ++886 2 2934 4373 E-Mail: [email protected] web: www.rikaline.com.tw  
Download from Www.Somanuals.com. All Manuals Search And Download.  
GPS-20 Operating Manual  
Rik a lin e  
Name  
Message ID  
Course  
Reference  
Course  
Example  
$GPVTG  
309.62  
T
Units  
Description  
VTG protocol header  
Degrees Measured heading  
True  
Degrees Measured heading  
Magnetic (1)  
Reference  
Speed  
M
0.13  
N
Knots  
Measured horizontal speed  
Knots  
Units  
Speed  
Units  
0.2  
K
Km/hr  
Measured horizontal speed  
Kilometers per hour  
Checksum  
<CR> <LF>  
*6E  
End of message termination  
(1) SiRF Technology Inc. does not support magnetic declination. All “course over ground” data are  
geodetic WGS84 directions.  
4.2 RTCM Received Data  
The default communication parameters for DGPS Input are 9600 baud, 8 data bits, stop bit, and no  
parity. Position accuracy of less than 5 meters can be achieved with the GPS-20 by using Differential GPS  
(DGPS) real-time pseudo-range correction data in RTCM SC-104 format, with message types 1, 5, or 9. As  
using DGPS receiver with different communication parameters, GPS-20 may decode the data correctly to  
generate accurate messages and save them in battery-back SRAM for later computing.  
14  
Rikaline Marketing Corp.  
5F-1, 125, Roosevelt Road, Sec. 5, Taipei, Taiwan 116  
Tel: ++886 2 2934 5456 Fax: ++886 2 2934 4373 E-Mail: [email protected] web: www.rikaline.com.tw  
Download from Www.Somanuals.com. All Manuals Search And Download.  
GPS-20 Operating Manual  
Rik a lin e  
5. Earth Datums  
5.1 Earth Datums  
The following is a list of the GPS-20 earth datum index and the corresponding earth datum name:  
Item  
1
2
Datum  
Reference Ellipsoid  
Clarke 1880  
Krassovsky  
Data name  
Data1.dat  
Data2.dat  
Adindan - Ethiopia  
Afgooye – Somalia  
3
4
5
6
7
8
Alaska, Conus – North American 1983  
Albania – S-42 (Pulkovo 1942)  
Argentina  
Australia  
Bahrain – Ain el ABD 1970  
Bangladesh  
GRS 1980  
Data3.dat  
Data63.dat  
Data4.dat  
Data70.dat  
Data5.dat  
Data6.dat  
Krassovsky 1940  
South American 1969  
Australian – National  
International  
Everest 1830  
9
Bolivia  
South American 1969  
Clarke 1880  
Data8.dat  
Data7.dat  
10 Botswana – ARC 1950  
11 Brazil  
12 Brunel, East Malaysia  
13 Canada – North American 1983  
14 Chile  
15 Colombia  
South American 1969  
Everest (Sabah & Sarawak)  
GRS 1980  
South American 1969  
South American 1969  
International  
Krassovsky 1940  
South American 1969  
International  
International  
International  
International  
International  
International  
International  
International  
International  
International  
International  
International  
Data9.dat  
Data37.dat  
Data10.dat  
Data13.dat  
Data12.dat  
Data11.dat  
Data64.dat  
Data14.dat  
Data29.dat  
Data15.dat  
Data16.dat  
Data17.dat  
Data18.dat  
Data19.dat  
Data20.dat  
Data21.dat  
Data22.dat  
Data23.dat  
Data24.dat  
Data25.dat  
Data26.dat  
Data27.dat  
Data28.dat  
Data30.dat  
Data32.dat  
Data31.dat  
Data33.dat  
Data65.dat  
Data34.dat  
Data35.dat  
Data65.dat  
Data53.dat  
Data67.dat  
Data36.dat  
Data38.dat  
Data39.dat  
Data40.dat  
Data42.dat  
Data41.dat  
Data43.dat  
16 Colombia – Provisional American 1956  
17 Czechoslovakia – S-42 (Pulkovo 1942)  
18 Ecuador  
19 European 1950 – Central Regional Mean  
20 European 1950 – Cyprus  
21 European 1950 – Eastern Regional Mean  
22 European 1950 – Egypt  
23 European 1950 – Finland, Norway  
24 European 1950 – Greece  
25 European 1950 – Iran  
26 European 1950 – Italy (Sardinia)  
27 European 1950 – Italy (Sicily)  
28 European 1950 – Malta  
29 European 1950 – Northern Regional Mean  
30 European 1950 – Portugal, Spain  
31 European 1950 – Southern Regional Mean International  
32 European 1950 – Tunisia  
33 European 1950 – Western Regional mean  
34 Guyana - South American 1969  
35 Hawaii-North American 1983  
36 Hong Kong  
37 Hu_Tsu_Shan Taiwan  
38 Hungary – S-42 (Pulkovo 1942)  
39 Indian 1960  
International  
International  
South American 1969  
GRS1980  
International  
International  
Krassovsky 1940  
Everest 1830  
Modified Airy  
Krassovsky 1940  
Clarke 1880  
Krassovsky 1940  
Clarke 1880  
GRS1980  
40 Ireland – 1965  
41 Kazakhstan – S-42 (Pulkovo 1942)  
42 Kenya, Tanzania- ARC 1960  
43 Latvia – S-42 (Pulkovo 1942)  
44 Liberia – 1964  
45 Mexico, central America  
46 OMAN  
Clarke 1880  
47 Pakistan  
Everest 1830  
South American 1969  
South American 1969  
Clarke 1866  
48 Paraguay - South American 1969  
49 Peru1 – South American 1969  
50 Philippines  
15  
Rikaline Marketing Corp.  
5F-1, 125, Roosevelt Road, Sec. 5, Taipei, Taiwan 116  
Tel: ++886 2 2934 5456 Fax: ++886 2 2934 4373 E-Mail: [email protected] web: www.rikaline.com.tw  
Download from Www.Somanuals.com. All Manuals Search And Download.  
GPS-20 Operating Manual  
Rik a lin e  
51 Poland – S-42 (Pulkovo 1942)  
52 Potsdam  
53 Puerto Rico – Virgin Islands  
54 Qatar national  
55 Qornoq – Greenland (SOUTH)  
56 Regional Mean  
57 Reunion – Mascarene Islands  
58 Romania – S-42 (Pulkovo 1942)  
59 Rome 1940 – Italy  
60 Saudi Arabia – Ain el Abd 1970  
61 Singapore  
62 South Africa  
63 Thailand 1975  
64 Tokyo_Japan  
65 Tokyo_Korea  
66 Tokyo_Mean  
67 Tokyo_Okinawa  
68 Trinidad, Tobago  
69 Venezuela  
70 Venezuela – Provisional American 1956  
71 WGS84  
Krassovsky 1940  
Bessel 1841  
Clarke 1866  
International  
International  
South American 1969  
International  
Krassovsky 1940  
International  
International  
Modified Fischer 1960  
Clarke 1880  
Everest 1830  
Bessel 1841  
Bessel 1841  
Bessel 1841  
Bessel 1841  
South American 1969  
South American 1969  
International  
Data68.dat  
Data71.dat  
Data44.dat  
Data45.dat  
Data46.dat  
Data48.dat  
Data47.dat  
Data69.dat  
Data49.dat  
Data50.dat  
Data51.dat  
Data52.dat  
Data54.dat  
Data60.dat  
Data61.dat  
Data59.dat  
Data62.dat  
Data55.dat  
Data57.dat  
Data56.dat  
Data58.dat  
WGS84  
5.2 Setting Syntax  
5.2.1 Manufacturing Default:  
Datum: WGS84.  
Baud Rate: 4800.  
Output: GGA, GSA, GSV, RMC.  
5.2.2 Datum change syntax:  
>DOS\Sirfprog /Fdataxx.dat –Px –Bx –Csh1  
-Px: x is com port, 1= COM1, 2 = COM2  
-Bx: x is baud rate, 4800, 9600, 19200 or 38400  
Example:  
Change Datum to WGS84,  
Sirfprog /Fdata58.dat –P1 –B4800 –Csh1 <Entry>  
After changing datum, the new datum will be kept in SRAM. If no power supplied to GPS-20 for more  
than 9 days, user must re-set datum when power on.  
16  
Rikaline Marketing Corp.  
5F-1, 125, Roosevelt Road, Sec. 5, Taipei, Taiwan 116  
Tel: ++886 2 2934 5456 Fax: ++886 2 2934 4373 E-Mail: [email protected] web: www.rikaline.com.tw  
Download from Www.Somanuals.com. All Manuals Search And Download.  
GPS-20 Operating Manual  
Rik a lin e  
6. Ordering Information  
6.1 Product Options  
6.1.1 Input Power  
GPS-20-5: 5V (Standard: TTL level, No backup battery)  
GPS-20-3: 3.3V (Standard: TTL level, No backup battery)  
6.2 Accessories  
A-10302 Active Antenna, 2-Meter, MCX straight connector  
A-10302-A Active Antenna, 2-Meter, MCX 90° connector  
A-10305 Active Antenna, 5-Meter, MCX straight connector  
A-10305-A Active Antenna, 5-Meter, MCX 90° connector  
Active Antenna with other connector is produced on demand.  
7. Warranty  
The GPS-20 is warranted to be free from defects in material and functions for one year from the date  
of purchase. Any failure of this product within this period under normal conditions will be replaced at  
no charge to the customers.  
17  
Rikaline Marketing Corp.  
5F-1, 125, Roosevelt Road, Sec. 5, Taipei, Taiwan 116  
Tel: ++886 2 2934 5456 Fax: ++886 2 2934 4373 E-Mail: [email protected] web: www.rikaline.com.tw  
Download from Www.Somanuals.com. All Manuals Search And Download.  

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