SEPTENTRIO PolaRx5TR, Reference Manual

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3 Command Line Reference
spim
gpim
setPPSINMonitor
getPPSINMonitor
Mode
off
on
RxControl: Navigation > Receiver Operation > Timing
By default, the receiver uses the PPS IN signal only at startup for initial synchronization. Dur-
ing operation, PPS IN is ignored and the receiver time is kept in sync by counting the cycles
of the 10-MHz REF IN reference. It is assumed that the phase of PPS IN remains constant
with respect to the 10-MHz reference, or in other words, that there are exactly 10 millions of
cycles of the 10-MHz reference between each PPS IN pulse.
In some cases, this assumption is not valid, for example when the PPS IN phase can
jump independently of the 10 MHz reference. When enabling PPS IN monitoring with the
setPPSINMonitor
command, the receiver continuously monitors the phase of the PPS IN
signal. In case of jump, the receiver resets and resynchronizes to the new PPS IN phase. This
ensures that the receiver time is always aligned with PPS IN. The jump detection threshold is
set to about one nanosecond.
Example
COM1> spim, on<CR>
$R: spim, on
PPSINMonitor, on
COM1>
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