Artesyn MVME5100, Programmer'S Reference Manual, Page: 97 / 318

Hawk PCI Host Bridge & Multi-Processor Interrupt Controller
MVME5100 Single Board Computer Programmer’s Reference (6806800H17B)
97
2.3.4 Endian Conversion
The PHB supports both big- and little-endian data formats. Since the PCI bus is inherently little-
endian, conversion is necessary if all PPC devices are configured for big-endian operation. The
PHB may be programmed to perform the endian conversion described below.
The section discusses the following topics:

When PPC Devices are Big-Endian on page 97

When PPC Devices are Little Endian on page 98

PHB Registers on page 99
2.3.4.1 When PPC Devices are Big-Endian
When all PPC devices are operating in big-endian mode, all data to/from the PCI bus must be
swapped such that the PCI bus looks big endian from the PPC bus’s perspective. This
association is true regardless of whether the transaction originates on the PCI bus or the PPC
bus.