Jackson Labs Micro-JLT GNSS, Руководство пользователя

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Micro-JLT GNSS™ User Manual
44 © 2019 Jackson Labs Technologies, Inc.
3.6.16 SYNChronization:HEAlth?
The SYNChronization:HEAlth? query returns a hexadecimal number indicating the system’s
health-status. Error flags are encoded in a binary fashion so that each flag occupies one single bit of
the binary equivalent of the hexadecimal health-status flag.
The following system parameters are monitored and indicated through the health-status indicator.
Individual parameters are ‘Ored’ together which results in a single hexadecimal value encoding the
following system status information:
As an example, if the unit is in GNSS receiver holdover, and the OCXO voltage is too high, and the
UTC phase offset is > 250ns then the following errors would be indicated:
1) UTC phase > 250ns: 0x4
2) OCXO voltage too high: 0x40
3) GNSS receiver in holdover: 0x10
‘Oring’ these values together results in:
0x40 | 0x10 | 0x4 = 0x54
The unit would thus indicate: HEALTH STATUS: 0x54
A health status of 0x0 indicates a properly locked, and warmed-up unit that is completely healthy and
does not have any pending events.
3.6.17 SYNChronization?
This query returns the results of the following queries:
SYNChronization:SOURce:MODE?
If the OCXO coarse-DAC is maxed-out at 255 HEALTH STATUS |= 0x1;
If the OCXO coarse-DAC is mined-out at 0 HEALTH STATUS |= 0x2;
If the phase offset to UTC is >250ns HEALTH STATUS |= 0x4;
If the run-time is < 300 seconds HEALTH STATUS |= 0x8;
If the GNSS receiver is in holdover > 60s HEALTH STATUS |= 0x10;
If the Frequency Estimate is out of bounds HEALTH STATUS |= 0x20;
If the power supply or OCXO voltage is too high HEALTH STATUS |= 0x40;
If the power supply or OCXO voltage is too low HEALTH STATUS |= 0x80;
If the short-term-drift (ADEV @ 100s) > 100ns HEALTH STATUS |= 0x100;
For the first 3 minutes after a phase-reset, or a coarsedac change: HEALTH STATUS |= 0x200;
If the GNSS receiver indicates a strong jamming signal of >=50
(range is 0 to 255) and is in holdover HEALTH STATUS |= 0x800;