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Functional Description
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2
When PPC Devices are Big-Endian
When all PPC devices are operating in big-endian mode, all data to/from
PCI must be swapped such that PCI looks big-endian from the PPC bus’s
perspective. This is shown in the following figure.
Figure 2-3. Big- to Little-Endian Data Swap
1916 9610
D
H
07-
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15-
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4
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L31-
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D0
D1
D2
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D5
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D7
D6
D5
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D3
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D1
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D0
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D7
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-1
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-2
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L07-
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L23-
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L31-
24
D7
D6
D5
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D1
D0
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24
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07-
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PPC Bus
64-bit PCI
PPC Bus
32-bit PCI