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Specify maximum wait time for external trigger


The data acquisition session ExternalTriggerTimeout property specifies the maximum amount of time in seconds the session waits for an external trigger before timing out. To disable the timeout, set ExternalTriggerTimeout to a value of Inf.


Specify External Trigger Timeout

Specify how long the session waits for an external trigger before timing out.

Create a session and click on the Properties link to display session properties.

s = daq.createSession('ni')
s = 

Data acquisition session using National Instruments hardware:
   Will run for 1 second (1000 scans) at 1000 scans/second.
   No channels have been added.
Properties, Methods, Events

                         AutoSyncDSA: false
                       NumberOfScans: 1000
                   DurationInSeconds: 1
                                Rate: 1000
                        IsContinuous: false
      NotifyWhenDataAvailableExceeds: 100
IsNotifyWhenDataAvailableExceedsAuto: true
          NotifyWhenScansQueuedBelow: 500
    IsNotifyWhenScansQueuedBelowAuto: true
              ExternalTriggerTimeout: 10
                      TriggersPerRun: 1
                              Vendor: National Instruments
                            Channels: ''
                         Connections: ''
                           IsRunning: false
                           IsLogging: false
                              IsDone: false
         IsWaitingForExternalTrigger: false
                   TriggersRemaining: 1
                           RateLimit: ''
                         ScansQueued: 0
               ScansOutputByHardware: 0
                       ScansAcquired: 0

Change the timeout to 15 seconds.

s.ExternalTriggerTimeout = 15;

Specify External Trigger with Disabled Timeout

Set an external trigger on a session, without a timeout.

Create a session with an external trigger, then set its ExternalTriggerTimeout to Inf.

s = daq.createSession('ni');
s.ExternalTriggerTimeout = Inf;