Jackson Labs Micro-JLT GNSS, Руководство пользователя

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Micro-JLT GNSS™ User Manual
3.6.11 SYNChronization:FEEstimate?
This query returns the Frequency Error Estimate, similar to the Allan Variance using a 1000s
measurement interval and comparing the internal 1PPS to GNSS 1PPS offset.
Values less than 1E-012 are below the noise floor, and are not significant.
3.6.12 SYNChronization:LOCKed?
This query returns the lock state (0=OFF, 1=ON) of the PLL controlling the OCXO.
3.6.13 SYNChronization:OUTput:1PPS:RESET <ON|OFF>
This command allows the generation of the 1PPS signal upon power-on without an external GNSS
antenna being connected to the unit. By default the unit does not generate a 1PPS signal until the
GNSS receiver has locked onto the Satellites.
With the command SYNC:OUT:1PPS:RESET ON the unit can be configured to generate an
asynchronous 1PPS output after power-on even if a GNSS antenna is not connected to the unit. Once
the GNSS receiver locks, the 1PPS signal will align itself to UTC time by stepping in 10 equally
spaced steps toward UTC alignment. The default setting is OFF which means
the 1PPS output
signal is disabled until proper GNSS lock is achieved .
3.6.14 SYNChronization:OUTput:1PPS:RESET?
This query returns the state of the SYNC:OUT:1PPS:RESET command, and may return ON or OFF.
3.6.15 SYNChronization:OUTput:1PPS:WIDTH <int> <ms | us>
[100us, 500ms]
This command allows configuration of the 1PPS active high pulse width. The default pulse width on
the standard Micro-JLT GNSS™ is 200 milliseconds and the pulse can be configured from 100
microseconds to 500 milliseconds. The integer parameter is followed by optional us (microsecond)
or ms (millisecond) units. The default unit is milliseconds. The output 1PPS signal is synchronized to
UTC (USNO) on its rising edge if 3D fix is available.
This command has the following format:
SYNChronization:OUTput:1PPS:WIDTH <int> <ms | us > [100us,500ms]
The following command returns the current pulse width setting stored in NV memory:
SYNChronization:OUTput:1PPS:WIDTH?
The unit of parameter for this command can be either us or ms. For example, command
SYNC:OUT:1PPS:WIDTH 200000us and command SYNC:OUT:1PPS:WIDTH 200ms will both
configure the pulse width to 200ms. If the 1PPS output signal is already available before sending this
command, a 1PPS pulse with the specified pulse width will be generated on the next second and
every second thereafter.