User`s guide

Supporting Hardware Triggers
5-27
Supporting Hardware Triggers
The toolbox supports three types of triggers:
• Immediate — Trigger fires when video input object is started.
• Manual — Trigger fires when user calls trigger function.
• Hardware — Trigger fires when externally defined conditions are met
The engine provides automatic support for immediate and manual triggers. If you
want your adaptor to support hardware triggers you must check to see if users have
specified a hardware trigger in your acquisition thread function. Before you start
acquiring frames from your device, insert a call to the IAdaptor member function
useHardwareTrigger() to determine if the frame acquisition loop should wait for a
hardware trigger to fire. If a hardware trigger is configured, insert device SDK calls
required to wait for trigger.
The following figure illustrates the frame acquisition loop with the test for hardware
trigger.