(c) Clock synchronization on GPS time
 1_ If a GPS signal is present and valid when the power is on, the
 clock synchronizes on the GPS time using labels 150 and 260.
 2_ If the signal is not present during synchronization, the clock
 dispalys dashes on all the digits. 

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 MMR - GPS SELECTED NAVAIDS Page on MCDU
 Figure 012

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 3 If the signal is present but not valid during synchronization,
_ the clock indicates 00:00:00.
 4 If the signal becomes not valid after synchronization, the
_ clock runs on its internal time base.
 (d) Display of GPS data on MCDU
 1 GPS MONITOR
_ (Ref. Fig. 013) The GPS data are displayed on the GPS MONITOR page of the MCDU. To get the GPS MONITOR page, push the DATA key on the MCDU, then the line key adjacent to the GPS MONITOR indication. The upper part is dedicated to GPS 1 data, the lower part to GPS 2 data. The following data are displayed:
 -GPS position (lat/long)
 -true track
 -GPS altitude
 -figure of merit (in meters)
 -ground speed
 -number of satellites tracked
 -mode.

R **ON A/C 051-099, 106-149, 204-299, 301-399, 401-499,
 2 PREDICTIVE GPS
_ (Ref. Fig. 014) The integrity prediction results given by the GPS portion of the MMR on Flight Management System (FMS) request are displayed on the PREDICTIVE GPS page of the MCDU (from the progress page which displays required navigation accuracy and estimated position accuracy and GPS PRIMARY indication). The prediction concerns the destination (DEST) and any pilot entered waypoint (WPT) and the integrity availability (HIL <
 0.3 Nm) is displayed by Yes (Y) or No (N) for the seven times defined by the five minutes increments for plus or minus 15 minutes around DEST or WPT.
 3 Progress page
_ The progress page indicates whether the GPS is used by the FMGC for navigation. If it is used, the GPS PRIMARY indication is displayed. If it is not used, the GPS PRIMARY LOST message is shown.
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 GPS - GPS MONITOR Page on MCDU
 Figure 013

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 GPS - PREDICTIVE GPS Page
 Figure 014

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 4_ MCDU scratchpad
 GPS PRIMARY in white or GPS PRIMARY LOST in amber show on the
 MCDU scratchpad.
 5_ SELECTED NAVAIDS page
 It is possible to select GPS for navigation computation within
 the FMS on the SELECTED NAVAIDS page.
 If you deselected GPS, the message GPS IS DESELECTED appears
 on the MCDU when a GPS approach starts.
 6_ ARRIVAL page
 To select a GPS approach, use the ARRIVAL page.
 **ON A/C ALL

 (e) Display of GPS messages on ND (Ref. Fig. 015)
 1 Display of GPS PRIMARY LOST amber message
_ This message is displayed at the bottom of the image in all the ND modes (except engine standby modes) when the GPS primary is lost (this message cannot be cleared from the MCDU). In this case, the GPS is not used for navigation (accuracy and integrity for the intended operation can still be met by the use of alternate navigation means).
 2 Display of GPS PRIMARY white message
_ This message is displayed at the bottom of the image in all the ND modes (except engine standby modes) when the GPS becomes primary (this message can be cleared from the MCDU).
 3 Display of GPS APP green message
_ This approach message is displayed at the top of the image in all the ND modes (except engine standby modes) when a GPS approach is selected in the flight plan.
 (2) Warning
 (a) GPS failure The GPSs are monitored by the both FWCs using a status word sent by each GPS. In case of GPS failure, the NAV GPS 1(2) FAULT message is displayed in the lower part of the upper ECAM DU. This message is accompanied by:
 -activation of the MASTER CAUT lights on the glareshield
 -aural warning: Single Chime (SC).
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 MMR - GPS Data Displayed on the NDs
 Figure 015

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 NOTE : The failure is reminded on the INOP SYSTEM page of the
____
 lower ECAM DU. The message displayed is GPS 1(2).

 (b)
 Loss of the GPS primary navigation When the GPS navigation is lost for any reason, the navigation function is degraded and reverts to the traditional navigation function with IRS positions and radio positions if available (in this case the RNP (Required Navigation Performance) features are still available). Warnings are generated to indicate the loss of GPS PRIMARY navigation:
　
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