User`s manual

Basic Operation & Standard Features
3-8
BASLER A600f
DRAFT
3.2.5 Controlling Exposure Start with an ExTrig Signal
The external trigger (ExTrig) input signal can be used to control the start of exposure. A rising
edge or a falling edge of the signal can be used to trigger exposure start. The Trigger_Mode
control register (see page 4-10) is used to enable ExTrig exposure start control, to select rising or
falling edge triggering, and to assign a physical input port to receive the ExTrig signal.
The ExTrig signal can be periodic or non-periodic. When the camera is operating under control of
an ExTrig signal, the period of the ExTrig signal determines the camera’s frame rate:
For example, if you are operating a camera with an ExTrig signal period of 20 ms (0.020 s):
So in this case, the frame rate is 50 fps.
The minimum high time for a rising edge trigger (or low time for a falling edge trigger) is 1 µs.
Exposure Modes
If you are triggering the camera with an ExTrig signal, two exposure modes are available,
programmable mode and level controlled mode.
Programmable Exposure Mode
When programmable mode is selected, the length of the exposure will be determined by the value
stored in the Shutter control register (see page 4-9). If the camera is set for rising edge triggering,
exposure starts when the ExTrig signal rises. If the camera is set for falling edge triggering,
exposure starts when the ExTrig signal falls. Figure 3-4 illustrates programmable exposure with
the camera set for rising edge triggering.
Figure 3-4: Programmable Exposure with Rising Edge Triggering
1
ExTrig period in seconds
------------------------------------------------------------------ frame rate=
1
0.020
--------------- 50 fps=
ExTrig
ExTrig Period
Exposure
(determined by shutter setting)