Motorola MTX series - Figure 2-3. Big- to Little-Endian Data Swap; When PPC Devices Are Big-Endian

Functional Description
http://www.motorola.com/computer/literature 2-15
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
DH07-00 DH15-08 DH23-16 DH31-2
4
DL07-00 DL15-08 DL23-16 DL31-24
D0 D1 D2 D3 D4 D5 D6 D7
D7 D6 D5 D4 D3 D2 D1 D0
D0 D1 D2 D3 D4 D5 D6 D7
AD63-56 AD55-48 AD47-40 AD39-32
AD31-24 AD23-16 AD15-08 AD07-00
DH07-00 DH15-08 DH23-16 DH31-24 DL07-00 DL15-08 DL23-16 DL31-24
D7 D6 D5 D4
D3 D2 D1 D0
AD31-24 AD23-16 AD15-08 AD07-00
PPC Bus
64-bit PCI
PPC Bus
32-bit PCI