Agilent Technologies 53220A, Руководство пользователя

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53220A/53230A User’s Guide 79
53220A/53230A Measurements 3
Using MEASure
Measurements using commands from the
MEASure
subsystem are made as the
command is executed, and are based on parameters specified within the syn-
tax. The results are sent to the instrument’s output buffer.
For example, the
MEASure
command:
MEAS:FREQ? 60.0, 1e-3, (@1)
takes a single measurement with five digit (1 mHz) resolution of an expected
60 Hz signal on channel 1. All other counter parameters (input configuration,
trigger sources, etc.), are set to values predefined for the given
MEASure
com-
mand, or remain unchanged from previously programmed values.
Because the measurement is taken immediately, changes to the counter config-
uration are limited to the parameters within the command.
Using CONFigure
Measurements using commands from the
CONFigure
subsystem allow the use
of low-level commands to change counter parameters before the measurement
is taken. For example, assume the following configuration is required:
• frequency measurement
• external trigger - positive slope
• trigger count = 2
• sample count (readings per trigger) = 5
• gate time = 5 ms
The
MEASure:FREQuency?
command cannot be used since it immediately
triggers a measurement after setting the trigger source to ‘internal’, the trigger
count to ‘1’, and the sample count to ‘1’. The gate time is set to 0.1 seconds.