u-blox ANTARIS 4, Руководство по системной интеграции

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your position is our focus
Wakeup conditions
Pin Trigger
EXTINT0 Rising edge
RxD1 or RxD2 Falling edge
Table 13: Possibilities to wakeup the receiver
the first bytes may get lost.
During off state driving RESET_N low can wake the receiver up. If the receiver configuration has not been saved
in BBR, the receiver will loose the actual configuration and revert to previous configuration.
4.2.7.4 Waking up the ANTARIS
®
4 GPS Receiver by RTC
The ANTARIS
®
4 GPS Receiver has an internal RTC, which is used to set a timeout to wake-up the receiver
without any external signal. This is used in the FixNOW™ Mode (FXN) (see Section 4.2.7).
Note The RTC wake-up timeout can only be set internally by the FixNOW™ function. There is no external
or manual access to the wake up timeout.
he FixNOW™ mode controls the Power Supply for the active antenna connected to the RF_IN pin. The voltage
supply shut down when the receiver goes to Off State.
4.2.7.6 Functional Overv
T has several to optimize the G r-Performan t specific user
applic ents:
Note When waking up a receiver from sleep- or backup state with a serial message (RxD1 or RxD2), a
number (at least 8) of 0xFF characters shall be send prior to the RXM-POSREQ message. Otherwise
Note When waking up the ANTARIS
®
4 GPS Receiver by EXTINT0 a position will be calculated.
4.2.7.5 Active Antenna Power Control with FixNOW™
T
will be
iew
he FXN mode
requirem
parameters PS- and Powe ce to mee
ation
Parameter Descrip n tio
T_on [s] Time the receiver stays on after achieving the first position fix with the flag 'position within limits' set.
If T_on is set to 0s, the receiver will shut down after the first valid fix as soon as the RTC is calibrated. If a new
iver will automatically increase the "startup ephemeris is needed to achieve the defined accuracy, the rece
acquisition time T_acq".
T_off [s] Time the receiver stays in Off State
Base TOW [s] Alignment of T_acq (start-up) to GPS Time of Week.
T_acq [s] Time the receiver tries to acquire SV before going to Off State, if SV acquisition is not successful.
T_acq_off [s] Time the receiver stays in Off State, when SV acquisition was not successful.
T_reacq [s] Time the receiver tries to reacquire as soon as a sky obstruction happens and no 2D or 3D fix is possible.
T_reacq_off [s] Time the receiver stays in Off State, after reacquisition was not successful.
Table 14: FXN mode parameter description
GPS Modules - System Integration Manual (SIM) (incl. Reference Design) Receiver Description
GPS.G4-MS4-05007-A1 Page 67