Dalsa PC2-Comp Express OC-P2EM-COMP0, User Manual

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Theory of Operation PC2-Comp Express
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
onboard frame buffer memory to compensate for PCI bus latency and comprehensive error
notification. Whenever PC2-Comp Express detects a problem, the user application is immediately
informed and can take appropriate action to return to normal operation.
The PC2-Comp Express is designed with a robust ACU (Acquisition and Control Unit), which
manages all six inputs. The ACU monitors in real-time, the acquisition state of each input. In general
these management processes are transparent to end-user applications. With the PC2-Comp Express,
applications ensure trigger-to-image reliability by following the rules defined below:
Trigger Signal Validity
External trigger signal noise or glitches are easily ignored by the ACU with its programmable
debouncing control. A parameter is programmed for the minimum pulse duration considered as a valid
external trigger pulse. For further information, refer to "External Trigger (Used or Ignored)" on page
25.
Acquisition Or Transfer Status
For each frame or field, a number of events are generated. An application can monitor these events to
track the image acquisition or to take appropriate action if there is a problem. The following events are
described in:
Acquisition Events:
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"External Trigger (Used or Ignored)" on page 25
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"Vertical Sync from Camera" on page 25
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"Frame Lost" on page 26
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"Start of Frame" on page 26
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"Start of Odd Field" on page 26
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"Start of Odd Field" on page 26
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"Start of Even Field" on page 26
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"End of Frame" on page 26
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"End of Field" on page 26
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"Start of Odd Field" on page 26
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"End of Even Field" on page 27