Basler ace acA1920-155, User Manual, Page: 122 / 326

Image Acquisition Control AW00123404000
112 Basler ace USB 3.0
6.4.1 Frame Start Trigger Mode
The main parameter associated with the frame start trigger is the Trigger Mode parameter. The
Trigger Mode parameter for the frame start trigger has two available settings: off and on.
6.4.1.1 Frame Start Trigger Mode = Off
When the Frame Start Trigger Mode parameter is set to off, the camera will generate all required
frame start trigger signals internally, and you do not need to apply frame start trigger signals to the
camera.
With the trigger mode set to off, the way that the camera will operate the frame start trigger depends
on the setting of the camera’s Acquisition Mode parameter:

If the Acquisition Mode parameter is set to single frame, the camera will automatically generate
a single frame start trigger signal whenever it receives an Acquisition Start command.

If the Acquisition Mode parameter is set to continuous frame, the camera will automatically
begin generating frame start trigger signals when it receives an Acquisition Start command.
The camera will continue to generate frame start trigger signals until it receives an Acquisition
Stop command.
The rate at which the frame start trigger signals are generated can be determined by the
camera’s Acquisition Frame Rate parameter:

If the parameter is not enabled, the camera will generate frame start trigger signals at the
maximum rate allowed with the current camera settings.

If the parameter is enabled and is set to a value less than the maximum allowed frame rate
with the current camera settings, the camera will generate frame start trigger signals at the
rate specified by the parameter setting.

If the parameter is enabled and is set to a value greater than the maximum allowed frame
rate with the current camera settings, the camera will generate frame start trigger signals at
the maximum allowed frame rate.
Exposure Time Control with the Frame Start Trigger Off
When the Trigger Mode parameter for the frame start trigger is set to off, the exposure time for each
frame acquisition is determined by the value of the camera’s Exposure Time parameter.
For more information about the camera’s Exposure Time parameter, see Section 6.5 on page 127 .
Keep in mind that the camera will only react to frame start triggers when it is in a
"waiting for frame start trigger" acquisition status. For more information about the
acquisition status, see Section 6.1 on
page 97 and Section 6.3 on page 103 .