Rainbow Electronics GM862-GPS - Manual (Page 116)

GM862-GPS Software User Guide
1vv0300729 Rev. 5 - 05/07/07
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5.7.5 Message 106 – Select Datum
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 datums.
(Local map datums are a best fit to the local shape of the earth and not valid worldwide.)
The command has the following syntax:
$PSRF106,<Datum>< checksum><CR><LF>
Examples:
1. Datum select TOKYO_MEAN
$PSRF106,178*32
The following table describes the command fields:
Name Example Unit Description
Message ID $PSRF106 PSRF106 protocol header
Datum 178 21=WGS84
178= TOKYO_MEA N
179= TOKYO_JAPAN
180= TOKYO_KOREA
181= TOKYO_OKINAWA
Checksum *32
<CR><LF> End of message termination