User`s guide

6 Acquiring Image Data
6-6
Setting the Values of Trigger Properties
In this section...
“About Trigger Properties” on page 6-6
“Specifying Trigger Type, Source, and Condition” on page 6-6
About Trigger Properties
Most trigger properties can be set in the same way you set any other image acquisition
object property: referencing the property as you would a field in a structure using dot
notation. For example, you can specify the value of the TriggerRepeat property, where
vid is a video input object created using the videoinput function.
vid.TriggerRepeat = Inf
For more information, see “Configuring Image Acquisition Object Properties” on page
5-16.
Some trigger properties, however, are interrelated and require the use of the
triggerconfig function to set their values. These properties are the TriggerType,
TriggerCondition, and TriggerSource properties. For example, some
TriggerCondition values are only valid when the value of the TriggerType property
is 'hardware'.
Specifying Trigger Type, Source, and Condition
Setting the values of the TriggerType, TriggerSource, and TriggerCondition
properties can be a two-step process:
1
Determine valid configurations of these properties by calling the triggerinfo
function.
2
Set the values of these properties by calling the triggerconfig function.
For an example of using these functions, see “Using a Hardware Trigger” on page
6-14.
Determining Valid Configurations
To find all the valid configurations of the TriggerType, TriggerSource, and
TriggerCondition properties, use the triggerinfo function, specifying a video input
object as an argument.