Easy I/O for DAQ Library Chapter 10
LabWindows/CVI Standard Libraries 10-38 © National Instruments Corporation
Parameters
Input device short integer Assigned by configuration utility.
counter string The counter to be used for the counting
operation.
sourceTimebase double USE_COUNTER_SOURCE: count TTL edges at
counter’s SOURCE pin; or supply a valid
internal timebase frequency to count the TTL
edges of an internal clock.
timebaseDivisor double The source frequency divisor.
gateMode unsigned
short integer Specifies how the signal on the counter's GATE
pin is used.
outputBehavior unsigned
short integer The behavior of the output signal when counter
reaches terminal count.
sourceEdge short integer The edge of the counter source or timebase signal
on which it decrements:
COUNT_ON_RISING_EDGE or
COUNT_ON_FALLING_EDGE.
Output taskID unsigned
long integer The reference number assigned to this operation.
You pass taskID to CounterStart,
CounterRead, and CounterStop.
Return Value
error short integer Refer to error codes in Table 10-5.
Parameter Discussion
counter is the counter to be used for the counting operation. The valid counters are shown in
Table 10-2, which is found in the Valid Counters for the Counter/Timer Functions subsection of
the Easy I/O for DAQ Library Function Overview section of this chapter.
sourceTimebase determines whether the counter uses its SOURCE pin or an internal timebase
as its signal source. Pass USE_COUNTER_SOURCE to count TTL edges at counter’s SOURCE
pin, or pass a valid internal timebase frequency to count the TTL edges of an internal clock.
Valid internal timebase frequencies are:
1000000 (Am9513)
100000 (Am9513)
10000 (Am9513)
1000 (Am9513)
100 (Am9513)
20000000 (DAQ-STC)
100000 (DAQ-STC)