imgSessionLineTrigSource

Usage

rval imgSessionLineTrigSource(SESSION_ID sid, uInt32 trigger, uInt32 polarity, uInt32 skipCount);

Purpose

Configures triggering per line for acquisition from a line scan camera. Use this function to require a trigger to start the acquisition of each line from a line scan camera.

Note  This function is obsolete. The replacement function is imgSessionLineTrigSource2, which incorporates the functionality of imgSessionLineTrigSource but also returns additional information.

Note  This function requires a camera that has the functionality to externally control the line rate. To implement this functionality, the external line rate signal must be cabled to one of the image acquisition control lines.

Parameters

Name	Type	Direction
sid	SESSION_ID	input
trigger	uInt32	input
polarity	uInt32	input
skipCount	uInt32	input
rval	Int32	output

Parameter Discussion

sid: valid SESSION_ID.

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

IMG_EXT_TRIG0	IMG_EXT_RTSI2
IMG_EXT_TRIG1	IMG_EXT_RTSI3
IMG_EXT_TRIG2	IMG_EXT_RTSI4
IMG_EXT_TRIG3	IMG_EXT_RTSI5
IMG_EXT_RTSI0	IMG_EXT_RTSI6
IMG_EXT_RTSI1

Note  IMG_EXT_TRIG ‹0..3› refers to the external trigger lines of the image acquisition device. IMG_EXT_RTSI ‹0..6› refers to the internal pins on the RTSI controller of the image acquisition device.

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.

skipCount: number of triggers to skip before acquiring a new line. For example, if you are using an encoder to trigger lines and it outputs 1,000 ticks per revolution, but you want to acquire only 10 lines per revolution, set this parameter to 99. Set this parameter to 0 to acquire a line on every trigger.

Return Value

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

For more information, refer to the Obsolete functions topic.