Pci-Graphics; Universe Ii's Involvement; Vmebus Domain - Motorola MVME2400 Series Programmer's Reference Manual

Programming Details
and Big-Endian mode, there should be no endian issues for the Ethernet
data. Big-Endian software must still however be aware of the byte-
swapping effect when accessing the registers of the PCI-Ethernet device.

PCI-Graphics

The effects of byte swapping on Big-Endian software must be considered
by Big-Endian software.
5
Note

Universe II's Involvement

Since PCI is Little-Endian and the VMEbus is Big-Endian, the Universe II
performs byte swapping in both directions (from PCI to VMEbus and from
VMEbus to PCI) to maintain address invariance, regardless of the mode of
operation in the processor's domain.

VMEbus Domain

The VMEbus is inherently Big-Endian and all devices connected directly
to VMEbus are expected to operate in Big-Endian mode, regardless of the
mode of operation in the processor's domain.
In Big-Endian mode, byte-swapping is performed by the Universe II and
then by the MPIC. The result has the desirable effect by being transparent
to the Big-Endian software.
In Little-Endian mode, however, software must be aware of the byte-
swapping effect from the Universe II and the address reverse-rearranging
effect of the MPIC.
5-14
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There are no graphics on the MVME2400 series boards.
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