Adimec Camera Link OPAL Series, Operating And Users Manual

Page: 40 / 86

OPERATING AND USER MANUAL OPAL-FAMILY
40
IMAGE CAPTURING AND VIDEO OUTPUT
NOTE: The selection and behavior of the control signals are explained in detail in par. 7.11 and 7.12.
Image Acquisition in delayed transfer mode (optional) 7.7
In delayed transfer mode camera timing is controlled by means of two external signals. The
parameters for integration time and frame period can still be set and read-out but have no meaning.
Refer to figure 7.6 for a simplified basic timing diagram.
Delayed transfer mode Figure 7.6:
The image integration starts at a rising edge of the trigger signal. Image integration stops at the falling
edge. Image read-out starts at the falling edge of another trigger control signal.
To simplify explanations in this chapter we will assume that image integration and image read-out are
controlled by CC1. The rising edge of CC1 is interpreted as a “start integrating” request; the falling
edge is interpreted as a “stop integrating” request. The rising edge of CC2 is interpreted as a “start
sending image data” request. The behavior of CC1 and CC2 is determined by the settings explained in
par. 7.11 and 7.12.
Taking into account the remarks and descriptions mentioned in par 7.1, one can conclude the
following restrictions on the trigger signal:
The time between two falling edges of the read-out trigger signal must be equal or longer than the •
minimum frame period valid for the image format programmed.
If a falling edge is detected too early, i.e. before the image is completely read out, then this event
is ignored.
To make use of the maximum speed possibilities of the camera it is generally necessary to •
generate a rising edge of the trigger signal before the previous image is completely read out.
For timing details see figure 7.7. See table 7.2 & 7.3 for the values of all timing parameters.
Timing details delayed transfer mode. Figure 7.7:
Integration image
Image read-out
CCD Operation
Camera Output
Control Signal #2
Control Signal #1
Exposure
control
Sensor
integration
Image
output
Frame
start
Output image
integrating
Exposure
Start event
Exposure
End event
exposure
Frame start event
Frame delay (see text)
td_it_end
td_output
td_it_bgn