Programming The Local Bus To Vmebus Map Decoders - Motorola MVME162FX Programmer's Reference Manual

D64
A24
A32
USR
SUP

Programming the Local Bus to VMEbus Map Decoders

This section includes programming information on the local bus to
VMEbus map decoders and the GCSR base address registers.
The local bus to VMEbus interface allows onboard local bus
masters access to off-board VMEbus resources. The address of the
VMEbus resources as viewed from the local bus is controlled by the
local bus slave map decoders, which are part of the local bus to
VMEbus interface. Four of the six local bus to VMEbus map
decoders are programmable, while the two I/O map decoders are
fixed. The first I/O map decoder provides an A16/D16 or A16/D32
space at $FFFF0000 to $FFFFFFFF which is the VMEbus short I/O
When this bit is high, the first map decoder responds
to VMEbus D64 block access cycles. When this bit is
low, the first map decoder does not respond to
VMEbus D64 block access cycles.
When this bit is high, the first map decoder responds
to VMEbus A24 (standard) access cycles. When this
bit is low, the first map decoder does not respond to
VMEbus A24 access cycles.
When this bit is high, the first map decoder responds
to VMEbus A32 (extended) access cycles. When this
bit is low, the first map decoder does not respond to
VMEbus A32 access cycles.
When this bit is high, the first map decoder responds
to VMEbus user (non-privileged) access cycles.
When this bit is low, the first map decoder does not
respond to VMEbus user access cycles.
When this bit is high, the first map decoder responds
to VMEbus supervisory access cycles. When this bit
is low, the first map decoder does not respond to
VMEbus supervisory access cycles.
LCSR Programming Model
2
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