Rohde & Schwarz R&S NRP - Measuring with Low-Level Commands; The Simplest Measurement; Configuration of the Trigger System

Annex: Remote Control - Commands R&S NRP
1144.1400.12 Annex - I.12 E-2
Measuring with low-level commands
Low-level commands allow the user to perform the most important modifications on the measurement
configuration. In the present context, low-level commands are all commands that do not belong to high-
level commands. These are in particular the commands of the SENSe, TRIGger and CALCulate
systems. Since the high-level commands combine different low-level commands, they allow a simpler
configuration of measurements.
Each measurement configuration should begin with the *RST command, which sets the R&S NRP to a
defined output state. The accurate settings are described in the documentation of remote control
command SYSTem:PRESet. The most important settings are listed below:
• Continuous measurements are stopped (INIT:CONT OFF)
• Offset correction are deactivated (SENSe:CORRection:OFFSet:STATe OFF,
SENSe:CORRection:DCYCle:STATe OFF, SENSe:CORRection:FDOFfset:STATe OFF).
• All other settings of the SENSe system depend on the sensor used and are specified in the
corresponding manual.
• The first 4 CALCulate blocks are set to sensors 1 to 4 (CALCulaten:MATH "(SENSn)").
• The values are measured as absolute values (CALulate:RELative:STATe OFF).
• Logarithmic units are used (UNIT:POWer dBm and UNIT:RATio dB).
The simplest measurement
The fastest way to obtain a result is to use the following sequence of commands
*RST
INIT
FETCh?
Normally, *RST will set the ContAv mode. The concept of smart-sensor technology provides that each
sensor determines the reset values of the assigned SENSe and TRIGger block. Thus, another mode
than ContAv may come after *RST with future sensors. Information is provided in the operating manual
of the sensor used.
INIT initiates the measurement. After *RST, the trigger system is set to "straight through" (TRIG:SOUR
IMM) so that the trigger system state changes to MEASURING via INITIATED and WAIT_FOR_TRG.
After the measurement has been completed, FETCh? delivers the result to the output queue from which
it can be fetched.
Configuration of the trigger system
Trigger source
After a measurement is started with INIT, the state WAIT_FOR_TRG is entered. This is a preliminary
stage to the measurement, which has been initiated so that the measurement may start with high
accuracy at a defined point in time. For this purpose, different sources can be defined for the trigger
event, which triggers the measurement. In manual operation, a trigger event is not expected in the
ContAv mode. Since the measurement is to be performed continuously, the trigger source
(TRIGger:SOURce) is set to IMMediate.