Microchip Technology GPS-2700, Руководство пользователя

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SCPI-Control Quick Start Instructions
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2020 Microchip Technology Inc. DS50003016A-page 55
SERV:TRAC <int > [0,255]
SERV:EFCS:FAST <float> [0.0, 500.0]
SERV:EFCD:FAST <int> [2, 4000]
SERV:PHASECO:FAST <float> [-500.0, 500.0]
SERV?
3.10.1 SERV:LOOP <ON | OFF>
This command enables or disables the servo loop for the selected servo loop. With the
loop disabled, no changes are made to the oscillator frequency control. Normally the
servo loop is left enabled.
The following command returns the current loop setting where 1 means enabled:
SERV:LOOP?
3.10.2 SERV:MODE <OFF | NORM | FAST | AUTO>
GPS-2700 with firmware revision 0.74 and later adds support for two different phase
loop time constant settings. This command allows auto-setting of all of the servo loop
time constants to factory-default values as described in Section 2.5 with one single
command entry.
This command is useful in setting the filter loop time constants for different mission pro-
files to accommodate different usage scenarios of the GPS-2700. The loop time con-
stant of the CSAC can be chosen with these settings.
The AUTO mode lets the firmware determine by itself which loop time constant is used,
thus optimizing the units’ performance dynamically depending on the environmental
effects on the CSAC. The AUTO setting will quickly react to phase perturbations and
will try to set NORM settings (long time constant) whenever the unit is in stable condi-
tions to minimize residual noise, and to improve the ADEV performance of the filtered
output as much as possible for a particular environment. NORM settings are useful in
stationary applications, whereas FAST settings are preferred for mobile applications
such as in vehicles, man-packs, or aircraft.
The following command returns the current mode setting:
SERV:MODE?
If SERV:MODE OFF is sent or in factory default settings, the SERV:MODE? query will
result in a Command Error response. By default, the servo mode is disabled and
NORM settings are used.
3.10.3 SERV:STAT?
GPS-2700 with firmware revision 0.74 and later adds support for two different phase
loop time constant settings. See Section 2.5 for details of recommended loop time con-
stant settings.
This query responds with the current loop parameter settings, NORMAL or FAST.
When the SERV:MODE command is configured to AUTO, the SERV:STAT? query
responds with the automatically selected loop parameter setting, NORMAL or FAST. If
the servo mode is currently in OFF setting, the SERV:STAT? query will result in a Com-
mand Error response.
3.10.4 SERV:DACG <float> [0.001, 10000]
This command is used for factory setup.