User`s guide

Chapter 5 - I/O Commands
COMBINED TIME MESSAGE (@@Gb)
Applicability: M12+ Positioning and Timing Receivers
This message allows the user to give the receiver an initial estimate of the current time and date.
If the receiver is tracking at least one satellite, the receiver will ignore any attempts to change the
time and date parameters using this command. Rather, the receiver will respond with currently
calculated time and date.
If the user inputs the @@Gb Combined Time, @@Ga Combined Position, and @@Cb Almanac
Input message to a defaulted receiver, the receiver will be in a ‘Warm Start’ condition, resulting in
a rapid TTFF. This procedure should be used with care. If any of the data is erroneous, the TTFF
time may actually be EXTENDED instead of shortened.
Default Values: Time = 12:00:00
Date = 1/1/99
GMT offset = 0:00
Legacy Code Compatibility: The @@Gb message was implemented in an identical fashion on the
Motorola M12 Oncore receiver.
Earlier ONCORE receivers such as the VP, GT+, SL, and UT+ utilized three different messages
to convey this information:
@@Ac – Date
@@Aa – Time
@@Ab - GMT Offset
Motorola GPS Products - M12+ User's Guide Revision 6.X 09FEB05
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