OPERATING AND USER MANUAL QUARTZ series CXP
32
Trigger configuration, accuracy and deglitch filter
6.4.8.
In the control modes of the camera (see section 6.4.5), a trigger determines the exact timing.
A trigger consists of a rising edge and a falling edge or vice versa, configurable by TriggerActivation.
In case of a TriggerActivation set to RisingEdge, the rising edge triggers the start of integration.
There are three possible triggers:
The CoaXPress trigger.
•
Trigger sequences have the highest priority.
The frame grabber manufacturer is to facilitate software that allows to send the trigger.
The camera’s IO_Connector.
•
can be connected to a hardware trigger (section 3.2).
PARAMETER NAME
INTERFACE
ACCESS
VISIBILITY
RANGE
DEFAULT
TriggerSource
IEnumeration
R/W
B
Trigger
IO_Connector
Trigger
TriggerActivation
IEnumeration
R/W
B
RisingEdge
FallingEdge
RisingEdge
TriggerDeglitchTime
Integer
R/W
E
0 to 255
0
The latency and accuracy of the triggers are shown in the table below.
TRIGGER TYPE
LATENCY / ACCURACY
CoaXPress trigger
3.4 us +/- 10 ns *)
camera IO_Connector
< 1.5 us from non-conductive to conductive
< 10 us from conductive to non-conductive **)
* It is adviced to inquire your framegrabber manufacturer if there is additional latency at the
framegrabber side.
** See section 3.2 for more details on the termination circuit.
Latency / Accuracy of the various triggers
Table 6.4:
To be able to handle glitches on possible heavily disturbed external trigger signals, a deglitch circuit
can be activated. This deglitch circuit will prevent short glitches to be interpreted as trigger signals.
The sensitivity of the deglitch circuit can be programmed via the TriggerDeglitchTime parameter.
By default the deglitch circuit is switched off (which represents value 0). When the value (x) is between
1 and 255, the input signal must be present for at least x µs, before it will be interpreted as a trigger
signal. This means that the start of integration is delayed with the set deglitch period. The end of
integration is also delayed with the deglitch period to ensure that the period of the external trigger
signal is the same as the length of the integration time.
Set Exposure mode and Exposure time
6.4.9.
The exposure modes (described in more detail in section 6.4.5) are selectable with the ExposureMode
parameter.
In exposure modes Timed and TimedTriggerControl, the exposure time (integration time) is
configurable in units of 1 µs with the ExposureTimeRaw parameter.
The sensor design dictates a minimum exposure time, Emin of 11.5
µs
. This is not included in the
ExposureTimeRaw and will be added to that set value.
