Phytec pciGrabber4x4, Руководство по оборудованию

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Delivery Contents / Technical Data
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PHYTEC Messtechnik GmbH 2008 L-720e_0
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Figure 25: Overloaded PCI bus
Figure 25 shows an effect which can appear with too high data rate. It
is good to see that the whole picture becomes streaky. The stripes
arise from the fact that some picture data in absence of the capacity of
the PCI bus can not be written fast enough in the main memory. The
data which cannot be transmitted get lost, because the video decoder
cannot cache them. Only the “old data” are available for certain ranges
of the pictures. In these ranges the “old picture data” are displayed and
so the picture becomes streaky.