Matrox Solios eA, Установка и справочник по оборудованию, Страница: 94 / 196

94 Chapter 4: Matrox Solios hardware reference
Timer trigger
The auxiliary I/O controller supports 10 timer-trigger input signals, which can
trigger any of the exposure timers. You can use the timer-trigger input signals to
synchronize the generation of an exposure signal with an external event. The
timer-trigger input signals can be received using auxiliary input signals or auxiliary
I/O signals in input mode; the timer-trigger input signal must meet the
specification of the auxiliary signal.
The trigger signal’s pulse width must be greater than two clock periods of the
timer. To determine the timer period, take the inverse of the timer’s clock
frequency. For example, if the clock frequency is 12.27 MHz, the minimum pulse
width is 2 x 1/12.27 MHz (approximately 163 nsec).
To avoid triggering a timer at an inappropriate time (for example, before the
current grab is complete), the auxiliary I/O controller supports an arm mechanism
for each timer. When a timer is set to generate an exposure signal upon a trigger
and the timer’s arm mechanism is disabled, the timer will react to all triggers
arriving from the specified trigger source. When the arm mechanism is enabled,
the timer must be armed to react to a trigger.
To generate an exposure signal upon a trigger, use the MIL-Lite function
MdigControl() with M_GRAB_EXPOSURE_TRIGGER_SOURCE . To
control the arm mechanism, use the MIL-Lite function MdigControl() with
M_GRAB_EXPOSURE_ARM... .
User-defined signals
Any auxiliary signal can be configured as a user-defined signal.
You can route any input signal that meets specifications to an auxiliary input signal
(or auxiliary I/O signals in input mode) configured as a user-defined signal; your
application can then interpret this user-defined signal as required.