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DAQmx_CreateCountEdgesChannel

Creates a task and channel to count number of edges.

Syntax

void avl::DAQmx_CreateCountEdgesChannel
(
	DAQmx_CreateCountEdgesChannelState& ioState,
	atl::Optional<const atl::String&> inDeviceID,
	const atl::Optional<const atl::String&> inCounter,
	avl::DAQmxActiveEdge::Type inActiveEdge,
	int inInitialCount,
	avl::DAQmxCountDirection::Type inCountDirection,
	avl::DAQmxTaskID& outTaskID
)

Parameters

Name	Type	Default	Description
ioState	DAQmx_CreateCountEdgesChannelState&		Object used to maintain state of the function.
inDeviceID	Optional<const String&>	NIL	Device alias, product name or serial number
inCounter	const Optional<const String&>	NIL	Name of a counter used to create virtual channel
inActiveEdge	DAQmxActiveEdge::Type		Active edge for counting
inInitialCount	int		Initial value
inCountDirection	DAQmxCountDirection::Type		Type of counting (incrementing and decrementing values)
outTaskID	DAQmxTaskID&		ID of a created task

Remarks

Device driver software

This filter is intended to cooperate with digital I/O cards using its vendor driver software. To be able to connect to a card it is required to install NI-DAQmx driver software. Currently Adaptive Vision Studio requires NI-DAQmx version 9.5.

NI-DAQmx driver software can be downloaded from the following website: http://www.ni.com/dataacquisition/nidaqmx.htm.

Device identification

When there is only one device connected to computer, inDeviceID field can be set to Auto. In this situation first available device will be found and connected.

inDeviceID can be used to pick one of multiple devices connected to computer. Set this field to Device alias (for example "Dev1"), product name or serial number. This parameters should be available in Measurement & Automation Explorer.

Multithreaded environment

This function is not guaranteed to be thread-safe. When used in multithreaded environment, it has to be manually synchronized.