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3.3.2 External Digital Trigger
An external digital trigger is generated when a TTL rising edge or falling edge is detected at
the SMB connector TRG IN on the front panel. As shown, trigger polarity can be selected
by software. Note that the signal level of the external digital trigger signal should be TTL
compatible, and the minimum pulse width 20 ns.
Pulse Width > 20ns
Pulse Width > 20ns
Rising Edge Trigger Event
Falling Edge Trigger Event
Figure 3-5: External Digital Trigger
3�3�3 Analog Trigger
An analog trigger is generated when AI input signal level is detected at the SMB connectors
CH0 to CH3 (selected by software). The trigger level is also selected by software.