Data Translation DT3130 Series, Руководство пользователя

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Chapter 2
18
By default, the external trigger is disabled. Through software, you
can enable the external trigger.
For the DT3131, DT3132, and DT3133 boards, you can specify
whether to start image acquisition when the board detects either a
low-to-high edge (rising-edge) transition or a high-to-low edge
(falling-edge) transition.
For the DT3131-ISO, DT3132-ISO, and DT3133-ISO boards, you can
specify whether to start image acquisition when the board detects
either a low-to-high (high level) transition or a high-to-low (low
level) transition on the input pin as referenced to the
Trigger
−
input pin. The difference between and Trigger
−
must be greater than 0.8 V for the signal to be considered a high level.
The incoming external trigger is qualified to be within a
programmable window and is forwarded to the device driver as an
interrupt. The interrupt is processed by the device driver to start the
acquisition and trigger the strobe, if desired. Refer to
page 20 for
more information on strobing.
Notes: Each device on the board requires its own interrupt resource.