National Instruments ISC-1783, User Manual

Internal Timing

The ISC-178x features two types of internally-timed modes: free-run mode and fixed-frame-

rate mode.
In free-run mode, the device acquires images at the maximum frame rate allowed by the

configuration. To operate in free-run mode, the Trigger Mode must be set to Off.
In fixed-frame-rate mode, you can specify a frame rate that is less than or equal to the

maximum frame rate. To operate in fixed-frame-rate mode, the Trigger Source must be set to

Fixed Rate and the Trigger Mode must be set to On. The rate is determined by the minimum of

the specified Acquisition Frame Rate and the Acquisition Frame Rate Limit attributes.

External Trigger

Use a trigger input to synchronize the ISC-178x with an external event, such as the assertion

of a signal generated by a proximity sensor. You can trigger the ISC-178x at rates up to the

maximum frame rate. You can configure external triggering with any of the Input lines or the

software as the trigger source.
Enable triggering with the Input lines as the trigger source in the following software programs:
•

In Vision Builder AI, select the 

Enable Trigger

 checkbox on the Trigger tab of the

Acquire Image (Smart Camera) step. Then select one of the 

Input

 lines from the Source

drop-down control.

•

In LabVIEW, set the value of the 

Trigger Mode

 to ON and the value of the 

Trigger

Source

 attribute to one of the available Input lines.

•

In MAX, select the 

Enable Trigger

 checkbox on the Triggering tab of the device

configuration page. Then select one of the 

Input

 lines from the Source drop-down

control.

Enable triggering with the software as the trigger source in the following software programs:
•

In Vision Builder AI, select the 

Enable Trigger

 checkbox on the Trigger tab of the

Acquire Image (Smart Camera) step. Then select 

Software

 from the Source drop-down

control. Use Send Software Trigger to trigger the smart camera.

•

In LabVIEW, set the value of the 

Trigger Mode

 to ON and the value of the 

Trigger

Source

 attribute to 

Software

.

•

In MAX, select the 

Enable Trigger

 checkbox on the Triggering tab of the device

configuration page. Then select 

Software

 from the Source drop-down control. Use Send

Software Trigger to trigger the smart camera.

Related Information

Connecting to Lighting Devices

 on page 12

Determining the Maximum Frame Rate

 on page 22

Delay and Activation

The following figure illustrates the relationship between an external trigger, a lightning strobe,

and the exposure time.

ISC-178x User Manual

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© National Instruments

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