Agilent Technologies Agilent 34980A, User Manual

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286 34980A User’s Guide
10
64-Bit Digital I/O Module with Memory and Counter
Initiated Measurement Mode
Measurements such as frequency, period, duty cycle, and pulse width
require an initiate command and a gate. The
SENSe:COUNter:INITiate
command is used to initiate (arm) the measurement. The measurement
is gated by either an internal (default) or the external gate source.
For measurements the external gate acts like an external trigger which
triggers the internal gate timer.
The gate source is set using the
SENSe:COUNter:SOURce
command.
The default gate source is
INTernal
. The gate is the aperture over which
the signal data is gathered. When the gate is internal, the measurement
begins as soon as the
INITiate
command is received.
Since the measurements are all derived from the same basic measurement,
you can retrieve the measured frequency, period, duty- cycle, and pulse
width from the same initiated and gated measurement. For example, the
following commands set the counter to measure the input signal for 1 ms
using the internal gate. The frequency, period, duty cycle, and pulse width
are returned as floating point numbers.
CONF:COUN:FREQ 1e-3, (@1301)
SENS:COUN:INIT (@1301)
SENS:COUN:FREQ? (@1301)
SENS:COUN:PER? (@1301)
SENS:COUN:PWID? (@1301)
SENS:COUN:DCYC? (@1301)
The
CONFigure:COUNter:FREQuency
command parameter sets the internal
gate time (to 1e- 3 or 1 ms in the above example). You can also set the
gate time using the
SENSe:COUNter:GATE:TIME
command.