PicoScope 3000A Series Prog rammer's Guide
77
Copyright © 2011-2013 Pico Technology Limited. All rights reserved.
ps3000abpg.en r9
2.12.48 ps3000aSetPulseWidthQualifier
PICO_STATUS ps3000aSetPulseWidthQualifier
(
short handle,
PS3000A_PWQ_CONDITIONS * conditions,
short nConditions,
PS3000A_THRESHOLD_DIRECTION direction,
unsigned long lower,
unsigned long upper,
PS3000A_PULSE_WIDTH_TYPE type
)
This function sets up pulse-width qualification, which can be used on its own for pulse-
width triggering or combined with level triggering or window triggering to produce more
complex triggers. The pulse-width qualifier is set by defining one or more structures
that are then ORed together. Each structure is itself the AND of the states of one or
more of the inputs. This AND-OR logic allows you to create any possible Boolean
function of the scope's inputs.
Applicability
All modes
Arguments
handle,
the handle of the required device
* conditions,
an array of
structures* specifying the conditions that should be applied to each
channel. In the simplest case, the array consists of a single element.
When there are several elements, the overall trigger condition is the
logical OR of all the elements. If
conditions
is
NULL
then the
pulse-width qualifier is not used.
nConditions,
the number of elements in the
conditions
array.
If
nConditions
is zero then the pulse-width qualifier is not used.
Range: 0 to
PS3000A_MAX_PULSE_WIDTH_QUALIFIER_COUNT
direction,
the direction of the signal required for the pulse width
trigger to fire. See
PS3000A_THRESHOLD_DIRECTION constants
for the list of possible values. Each channel of the oscilloscope
(except the EXT input) has two thresholds for each direction—for
example,
—so that
one can be used for the pulse-width qualifier and the other for the
level trigger. The driver will not let you use the same threshold for
both triggers; so, for example, you cannot use
as
the
direction
argument for both
and
at the same time. There is no such
restriction when using window triggers.
lower,
the lower limit of the pulse-width counter, measured in
samples.
upper,
the upper limit of the pulse-width counter, measured in
samples. This parameter is used only when the type is set to
or