User's Manual

Chapter 3 Advanced Programming with NI-IMAQdx
NI-IMAQdx User Manual 3-8 ni.com
• TriggerParameter—Certain trigger modes require an additional
parameter. Refer to the following sections to see if the optional
parameter is required.
Trigger Mode 0
With trigger mode 0, the camera starts frame integration when the external
trigger input changes to an active value. The frame is exposed for a duration
specified by the shutter attribute before the camera transfers the image to
the host computer. No optional parameter is required.
Figure 3-3. Timing Diagram for Trigger Mode 0
Trigger Mode 1
With trigger mode 1, the camera starts frame integration when the external
trigger input changes to an active value. The frame is exposed while the
external trigger is active. When the trigger becomes inactive, the camera
stops frame integration and transfers the image to the host computer. No
optional parameter is required.
Figure 3-4. Timing Diagram for Trigger Mode 1
Trigger
Exposure
Transmission
Frame N Frame N + 1 Frame N + 2
Start Delay Start Delay Start Delay
Start Delay Start Delay Start Delay
Frame
N + 1
Frame
N
Frame
N + 2
Trigger
Exposure
Transmission
Frame N Frame N + 1 Frame N + 2
Start Delay Start Delay Start Delay
Start/Stop
Delay
Start/Stop
Delay
Start/Stop
Delay
Frame
N + 1
Frame
N
Frame
N + 2