Advantech iDAQ-731, User Manual

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iDAQ-731_751_763D User Manual 26
3.4.2 Streaming Digital Input Acquisition
For a streaming acquisition, the number of samples to be acquired is set to infinite.
The acquisition starts when a start trigger is received and continues until a stop trig -
ger is received as shown in Figure 3.14.
Figure 3.14 Streaming acquisition.
Both the start trigger and the stop trigger can come from a software command or a
hardware signal. If a hardware signal is used, the start (for the start trigger) or the
stop (for the stop trigger) of the acquisition can also be delayed. Refer to the device
specifications for possible signal sources.
3.4.3 Retriggerable Digital Input Acquisition
The acquisition can be retriggerable. When re-trigger is enabled, after the acquisition
stops, it restarts whenever the required trigger is received, and reconfiguration of the
acquisition is not required.
Figures 3.15 to 3.18 show examples of retrigger acquisition for post-trigger, pre-trig
-
ger, about-trigger, and streaming acquisitions, respectively. In a post-trigger acquisi -
tion, a start trigger is ignored while the acquisition is in progress. In an about-trigger
acquisition, a stop trigger is ignored while the acquisition is being stopped.
Figure 3.15 Post-trigger acquisition with retrigger.