Matt,
The AnalogTriggerEvent may be the event you want to use, but it sounds like the AlarmEvent may better fit your application. With the AlarmEvent, you can specify both a high limit and a low limit. Events are fired when the specified channel exceeds the high limit, returns back from beyond the high limit, exceeds the low limit, or returns back from beyond the low limit. You can choose which events to monitor. Below, I have included a link to a document detailing the use of DAQ Events in various programming environments:
An Overview of DAQ Events and OccurrencesGood luck with your application.
Spencer S.