Phytec pciGrabber4x4, Руководство по оборудованию

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pciGrabber-4x4
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PHYTEC Messtechnik GmbH 2008 L-720e_0
Figure 50: Return Values of ‚Data_Present‘
Bits 2 and 3 are set to 1, as soon as an even or odd image was
completely recorded. Those bits are used, in case only one image
should be taken (single-shot, defined by
Set_Image ). The bits remain
set until a new digitization is started.
Caution:
Don’t call the status too often during digitization, since each inquiry
will occupy the PCI Express / PCI-bus, which might hinder the data
transfer of the Grabber. You might include delay times between in-
quiries, in order to avoid slowing down digitization.
Please pay attention to evaluate the correct bits, which correspond to
the actual mode, since otherwise your program might access the data
during the wrong time interval.
Figure 51: Timing Diagram of the Return Parameter of ‚Data_Present()