Vmebus Domain - Motorola MVME5100 Manual

7 Programming the MVME5100

VMEbus Domain

The VMEbus is inherently big-endian. All devices connected directly to the VMEbus must
operate in big-endian mode, regardless of the mode of operation in the processor's domain.
In big-endian mode, byte-swapping is performed first by the Universe ASIC and then by the
PHB. The result is transparent to big-endian software (a desirable effect).
In little-endian mode, however, software must take the byte-swapping effect of the Universe
ASIC and the address reverse-rearranging effect of the PHB into account.
For further details on endian considerations, refer to the MVME5100-Series Single Board
Computer Programmer's Reference Guide.
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MVME5100 Installation and Use (V5100A/IH5)