User`s guide

7 Using Events and Callbacks
Events and Callback Function Properties (Continued)
Event Callback Proper ty D es cription
Timer
TimerFcn
The toolbox generates a timer event when a specified
amount of time expires. Time is measured relative
to when the object starts running. You use the
TimerPeriod property to specify the amount of time.
Note Some timer events might not execute if your
system is significantly slowed or if the
TimerPeriod
is set too small.
When a tim er event occurs, the toolbox executes the
function specified by the
TimerFcn property.
Trigger
TriggerFcn
The toolbox generates a trigger event when a
trigger executes. The video input object executes
immediate triggers. Yo u execute manual triggers by
calling the
trigger function. The image acquisition
device executes hardware triggers when a specified
condition is m et.
When a trigger event occurs, the toolbox exe cute s
the function s pecified by the
TriggerFcn property.
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