Giga-tronics 8650A Series, Руководство по эксплуатации

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Remote Operation
Manual 31470, Rev. E, April 2001 3-5
3.2 SCPI Command Interface
This section details operation of the 8650A power meter using the SCPI (Standard Communications for
Programmable Instruments) interface commands. A SCPI command reference is presented in Table 3-3
and the sections that follow.
SCPI commands promote consistency in definition of a common instrument control and measurement
command language. The structured approach of the SCPI standard offers test system design engineers a
number of system integration advantages that achieve considerable efficiency gains during control
program development.
SCPI compatible instrument commands are structured from a common functional organization or model
of a test instrument (see Figure 3-1). Most of the power meter configuration and measurement functions
fall within the Measurement Function Block and the Trigger Subsystem of the SCPI instrument model.
The 8650A uses the Sense Subsystem of the Measurement Function Block to implement commands
that apply specifically to the individual power sensors; sensor 1, and sensor 2. For example, the
SENSe2:CORRection:OFFSet command corrects for the attenuation of a signal that passes through an
attenuator or coupler before it is measured by power sensor 2. Figure 3-1 illustrates the SCPI subsystem
model.
3.2.1 Sensor Calibration and Zero
The Calibration subsystem performs sensor calibration and zeroing. CALibrate:STATe n selects if the
calibration data is applied or not. If STATe is ON, then the instrument uses the calibration data for
correction. If STATe:OFF is selected, then no calibration using the calibration data will be made. The
CALibrate:ZERO subsystem controls the autozero calibration of the sensor.
3.2.2 Sensor and Channel Configuration
The Calculate subsystem of the Measurement Function Block contains commands that define the form
of the measured data from sensor 1 and sensor 2. Calculate commands define the configuration of the
two Software Calculation Channels. For example, the CALC1:POW 1 command configures channel 1
to report the power level as measured by sensor 1. CALC2: RAT 2,1 configures channel 2 to report the
ratio of power levels, sensor 2 over sensor 1.
Figure 3-1: SCPI Subsystem Model
NOTE:
Throughout this manual, some commands will be in both upper- and lower-case, such
as CALCulate and MEMory. The uppercase is the required input. The whole word can be used if
desired. If the whole word is used, it must be used in it’s entirety. For example, CALCulat will not
be recognized as a valid command.
☛ ☛ ☛ ☛
SENS
e
CALC
ulate
CAL
ibrate
TRIG
ger
MEM
ory