User guide

Hardware Options and Software Licenses
3.5.1.4 Configuration
The GPS option card is configurable via static parameters to allow the user to select
between a redundant and non-redundant configuration and also to allow the user to
select automatic revert to primary input, when a valid signal is re-established. The
set up of the SFN and associated GPS Interface Module is described in Annex H,
Setting up the SFN Functionality.
3.5.2 Static Parameters
Table 3.14 lists all the static parameters associated with the GPS function.
Table 3.14 Static Parameters (GPS)
Name Description Value
GPS Terminate Input A
High impedance or 50 Ω termination
Enable/Disable
GPS Terminate Input B
High impedance or 50 Ω termination
Enable/Disable
Locking of the Multiplexer clock to GPS 10 MHz is selected using static parameters
(see Annex C, Static Parameters) under reference clock option. The options are
similar to HSync (redundant, revert, etc.)
Other Static Parameters are to do with terminating the inputs. Select Terminate
(50 Ω) if the input is the last in chain, or high-impedance (not-terminated) if the
GPS signals are chained to other MX8400s.
3.5.3 Alarms
3.5.3.1 Non-redundant Configuration
In a non-redundant configuration the GPS option card alarms raised to nCC in the
event of input failures are as defined in Table 3.15.
Table 3.15 GPS Interface Module Input Failure Alarms (Non-redundant
Configuration)
Primary GPS Inputs Alarm Severity
Present None
Missing Critical
3.5.3.2 Redundant Configuration
In a redundant configuration the GPS option card, alarms raised to nCC in the event
of input failures are as defined in Table 3.16.
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