imgSessionTriggerConfigure2

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Updated2023-02-21
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Usage

rval imgSessionTriggerConfigure2(SESSION_ID sid, IMG_SIGNAL_TYPE triggerType, uInt32 triggerNumber, uInt32 polarity, uInt32 timeout, uInt32 action);

Purpose

Configures an acquisition to start based on an external trigger.

Parameters

Name	Type	Direction
sid	SESSION_ID	input
triggerType	IMG_SIGNAL_TYPE	input
triggerNumber	uInt32	input
polarity	uInt32	input
timeout	uInt32	input
action	uInt32	input
rval	Int32	output

Parameter Discussion

sid: valid SESSION_ID.

triggerType: type of trigger line to use. triggerType can be one of the following constants:

Note To use the ISO_IN or RS422_IN signals on the NI PCI-1426, select External as the Trigger Type for your function and choose ISO In or RS-422 In as the Signal Level for the trigger line in Measurement & Automation Explorer (MAX).

IMG_SIGNAL_EXTERNAL

IMG_SIGNAL_RTSI

IMG_SIGNAL_ISO_IN

triggerNumber: number of the trigger line to use.

polarity: polarity of the trigger line. polarity can be one of the following constants:

IMG_TRIG_POLAR_ACTIVEL	Triggers on a falling edge.
IMG_TRIG_POLAR_ACTIVEH	Triggers on a rising edge.

timeout: time, in milliseconds, to wait for the trigger to occur. Use IMG_TIMEOUT_INFINITE to wait indefinitely.

action: action to take when the trigger edge occurs. The following are valid values for action:

IMG_TRIG_ACTION_NONE	Clears the trigger.
IMG_TRIG_ACTION_CAPTURE	Starts acquiring.
IMG_TRIG_ACTION_BUFLIST	Acquires the buffer list once.
IMG_TRIG_ACTION_BUFFER	Acquires a single image.
IMG_TRIG_ACTION_STOP	Stops the acquisition.

Note When using IMG_TRIG_ACTION_STOP, the device will continue acquiring a variable number of post-trigger buffers before stopping the acquisition. Use the IMG_ATTR_NUM_POST_TRIGGER_BUFFERS attribute to set the number of post-trigger buffers.

Return Value

This function returns 0 on success. On failure, this function returns an error code. For information about the error code, call imgShowError.