Holux GR-211, Руководство пользователя

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HOLUX
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Table 5-10 contains the values for the following example:
$GPVTG,309.62,T, ,M,0.13,N,0.2,K*6E
Table 5-10 VTG Data Format
Name Example Units Description
Message ID $GPVTG VTG protocol header
Course 309.62 degrees Measured heading
Reference T True
Course degrees Measured heading
Reference M Magnetic(1)
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
1. SiRF Technology Inc. does not support magnetic declination. All “course over ground” data are geodetic
WGS84 directions.
5.2 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 GR-211 by using Differential GPS (DGPS)
real-time pseudo-range correction data in RTCM SC-104 format, with message types 1,2, or 9. As using
DGPS receiver with different communication parameters, GR-211 may decode the data correctly to generate
accurate messages and save them in battery-back SRAM for later computing.
6. Earth Datums
6.1 Earth Datums
The following is a list of the GR-211 earth datum index and the corresponding earth datum name:
Item Datum Reference Ellipsoid Data name
1 Adindan - Ethiopia Clarke 1880 Data1.dat
2 Afgooye – Somalia Krassovsky Data2.dat
3 Alaska, Conus – North American 1983 GRS 1980 Data3.dat
4 Albania – S-42 (Pulkovo 1942) Krassovsky 1940 Data63.dat
5 Argentina South American 1969 Data4.dat
6 Australia Australian – National Data70.dat
7 Bahrain – Ain el ABD 1970 International Data5.dat
8 Bangladesh Everest 1830 Data6.dat
9 Bolivia South American 1969 Data8.dat
10 Botswana – ARC 1950 Clarke 1880 Data7.dat
11 Brazil South American 1969 Data9.dat
12 Brunel, East Malaysia Everest (Sabah & Sarawak) Data37.dat
13 Canada – North American 1983 GRS 1980 Data10.dat
14 Chile South American 1969 Data13.dat
15 Colombia South American 1969 Data12.dat
16 Colombia – Provisional American 1956 International Data11.dat
17 Czechoslovakia – S-42 (Pulkovo 1942) Krassovsky 1940 Data64.dat
18 Ecuador South American 1969 Data14.dat
19 European 1950 – Central Regional Mean International Data29.dat
20 European 1950 – Cyprus International Data15.dat