Chapter 3
Hardware Overview
©
National Instruments Corporation
3-9
In high-hysteresis analog triggering mode, the trigger is generated when
the signal value is greater than highValue, with the hysteresis specified
by lowValue, as shown in Figure 3-9.
Figure 3-9.
High-Hysteresis Analog Triggering Mode
In low-hysteresis analog triggering mode, the trigger is generated when
the signal value is less than lowValue, with the hysteresis specified by
highValue, as shown in Figure 3-10.
Figure 3-10.
Low-Hysteresis Analog Triggering Mode
The analog trigger circuit generates an internal digital trigger based on
the analog input signal and the user-defined trigger levels. This digital
trigger can be used by any of the timing sections of the DAQ-STC,
including the analog input, analog output, and general-purpose
counter/timer sections. For example, the analog input section can be
configured to acquire n scans after the analog input signal crosses a
specific threshold. As another example, the analog output section can
be configured to update its outputs whenever the analog input signal
crosses a specific threshold.
highValue
Trigger
lowValue
highValue
Trigger
lowValue
PCI_E.book Page 9 Thursday, June 25, 1998 12:55 PM
