Measurement Computing PCI-DAS6071 - Manual (Page 19)

PCI-DAS6071 User's Guide Functional Details
19
A/D START TRIGGER signal
Use the A/D START TRIGGER signal for conventional triggering (when you only need to acquire data after a
trigger event). Figure 7 shows the A/D START TRIGGER signal timing for a conventionally triggered
acquisition.
Figure 7. Data acquisition example for conventional triggering
The A/D START TRIGGER source is programmable and may be set to any of the AUXIN inputs or to the
DAQ-Sync DS A/D START TRIGGER input. The polarity of this signal is also programmable to trigger
acquisitions on either the positive or negative edge.
The A/D START TRIGGER signal is also available as an output and can be programmed to appear at any of the
AUXOUT outputs. Refer to Figure 8 and Figure 9 for A/D START TRIGGER input and output timing
requirements.
Figure 8. A/D START TRIGGER input signal timing
Figure 9. A/D START TRIGGER output signal timing
The A/D START TRIGGER signal is also used to initiate pre-triggered DAQ operations (when you need to
acquire data just before a trigger event). In most pre-triggered applications, the A/D START TRIGGER signal
is generated by a software trigger. The use of A/D START TRIGGER and A/D STOP TRIGGER in pre-
triggered DAQ applications is explained next.
A/D Start Trigger
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