IMAQ Configure Trigger3 VI

NI-IMAQ VI

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IMAQ Configure Trigger3 VI

Installed With: NI Vision Acquisition Software

Configures the trigger conditions for an acquisition. Use this VI before any acquisition VI to setup a triggered image acquisition.

IMAQ Configure Trigger3

Frame timeout (ms) specifies the amount of time in milliseconds that NI-IMAQ waits for the trigger to occur and an image to be captured.

Polarity specifies the polarity of the trigger signal.

The following values are valid.

Rising Edge (0)	Sets the polarity to rising edge.
Falling Edge (1)	Sets the polarity to falling edge.

IMAQ Session In identifies the device.

Type specifies the type of the trigger signal.

The following values are valid.

Note Scaled Encoder is valid only when Trigger each line is selected for the Trigger action on the front panel. Use the Divide Factor property to configure the amount of scaling to apply to the Scaled Encoder signal. Refer to Scaled Encoder Signal for an overview of the Scaled Encoder signal. Software Trigger is valid only for the NI 17xx smart cameras.

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 as the Signal Level for the trigger line in Measurement & Automation Explorer (MAX).

External (0)	Use an external trigger for the trigger.
RTSI (1)	Use an RTSI line for the trigger.
ISO In (2)	Use an isolated input for the trigger.
Scaled Encoder (5)	Use scaled encoder counts for the trigger.
Software Trigger (6)	Use a software trigger for the trigger.

Line Number specifies the number of the trigger.

Action specifies if an assertion edge of this trigger line should start an acquisition.

The following values are valid:

Note When using Trigger end of acquisition, the device will continue acquiring a variable number of post trigger buffers before stopping the acquisition. Use the Number of Post Trigger Buffers property to set the number of post trigger buffers.

Disabled (0)	Triggering is disabled.
Trigger start of acquisition (1)	When the assertion edge of the trigger is received, the acquisition is started.
Trigger start of each buffer list (2)	When the assertion edge of a trigger is received, the buffer list is acquired. If the acquisition is continuous, buffer index 0 always waits on a trigger before acquiring.
Trigger each buffer (3)	Each buffer waits for a trigger before acquiring an image into the buffer.
Trigger each line (line scan) (4)	Each line is triggered. This is useful when using an encoder to acquire line scan images.
Trigger end of acquisition (5)	When the assertion edge of the trigger is received, the acquisition is stopped.

error in (no error) describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node.

	status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE.
	code code is the number identifying an error or warning. If status is TRUE, code is a non-zero error code. If status is FALSE, code can be zero or a warning code. Use the error handler VIs to look up the meaning of this code and to display the corresponding error message.
	source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.

Delayspecifies how long the active edge of the Trigger is delayed from the point when the Trigger is asserted.

Valuespecifies the length of the Delay.

Units specifies the Units for the Value parameter.

The following values are valid:

Note A non-zero Delay is only supported for NI 17xx smart cameras when the trigger Action is set to Trigger each buffer.

Scaled Encoder Counts (4)	The delay is measured in scaled encoder counts.
Milliseconds (5)	The delay is measured in milliseconds.

Skip trigger (linescan only) is the number of triggers to skip before acquiring a new line.

This feature is useful when using an encoder to trigger lines. For example, you may have an encoder that outputs 1,000 ticks per revolution. If you need only 200 lines per revolution, set Skip trigger to 4.

Note This input is valid only when using a line scan camera.

IMAQ Session Out has the same value as IMAQ Session In.

error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out indicator on the front panel and select Explain Error from the shortcut menu for more information about the error.

	status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.
	code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code.
	source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.

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