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Xtium2-CXP PX8 Reference
Xtium2-CXP PX8 User's Manual
Trigger to Image Reliability
Trigger-to-image reliability incorporates all stages of image acquisition inside an integrated
controller to increase reliability and simplify error recovery. The trigger-to-image reliability model
brings together all the requirements for image acquisition to a central management unit. These
include signals to control camera timing, on-board frame buffer memory to compensate for PCI bus
latency, and comprehensive error notification. If the Xtium2-CXP PX8 detects a problem, the
application can take appropriate action to return to normal operation.
The Xtium2-CXP PX8 is designed with a robust ACU (Acquisition and Control Unit). The ACU
monitors in real-time, the acquisition state of the input plus the DTE (Data Transfer Engine) which
transfers image data from on-board memory into PC memory. In general, these management
processes are transparent to end-user applications. With the Xtium2-CXP PX8, applications ensure
trigger-to-image reliability by monitoring events and controlling transfer methods as described
below:
Supported Events and Transfer Methods
Listed below are the supported acquisition and transfer events. Event monitoring is a major
component to the Trigger-to-Image Reliability framework.
Acquisition Module Events
Acquisition events pertain to the acquisition module. They provide feedback on the image capture
phase.
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External Trigger (Used/Ignored)
Generated when the external trigger pin is asserted, which indicates the start of the
acquisition process. There are two types of external trigger events: ‘Used’ or ‘Ignored’.
Following an external trigger, if the event generates a captured image, an External Trigger
Used event will be generated (CORACQ_VAL_EVENT_TYPE_EXTERNAL_TRIGGER).
If there is no captured image, an External Trigger Ignored event will be generated
(CORACQ_VAL_EVENT_TYPE_EXTERNAL_TRIGGER_IGNORED). An external trigger event is
ignored if the event rate is higher than the possible frame rate of the camera.
When using an active high/low or double pulse rising/falling edge trigger detection, the 2
nd
pulse will generate the External Trigger End event
(CORACQ_VAL_EVENT_TYPE_EXTERNAL_TRIGGER_END).
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Start of Frame
Event generated during acquisition, with the detection of the start of a video frame by the
board acquisition hardware. The Sapera event value is
CORACQ_VAL_EVENT_TYPE_START_OF_FRAME.
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End of Frame
Event generated during acquisition, with the detection of the end of a video frame by the
board acquisition hardware. The Sapera event value is
CORACQ_VAL_EVENT_TYPE_END_OF_FRAME.
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Data Overflow
The Data Overflow event indicates that there is not enough bandwidth for the acquired data
transfer without loss. Data Overflow would occur with limitations of the acquisition module
and should never occur.
The Sapera event value is CORACQ_VAL_EVENT_TYPE_DATA_OVERFLOW.
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Frame Valid
Event generated on detection of the start of a video frame by the board acquisition
hardware. Acquisition does not need to be active; therefore, this event can verify a valid
signal is connected. The Sapera event value is:
CORACQ_VAL_EVENT_TYPE_VERTICAL_SYNC.
