Motorola MVME1603, Installation And Use Manual

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Memory Maps
2-10
2
Notes
1. The IBC (PCI/ISA bridge) performs subtractive decoding in this range
and forwards the PCI memory cycle to the ISA if DEVSEL
∗
is not
detected.
2. The VME2PCI ASIC can be programmed to claim some of this address
range to forward the PCI memory cycle to the VMEchip2.
VMEbus Memory Map
The VMEbus is programmable. The mapping of local resources as viewed
by VMEbus masters varies among applications.
The VMEchip2 ASIC includes a user-programmable map decoder for the
VMEbus-to-local-bus interface. The map decoder enables you to program
the starting and ending address and the modifiers to which the
MVME1603/1604 responds.
The VMEchip2 also includes a user-programmable map decoder for the
GCSRs (global control/status registers, accessible from both the VMEbus
and the local bus). The GCSR map decoder allows you to program the
starting address of the GCSRs in the VMEbus short I/O space.
The VME2PCI ASIC supplies the interface between the PCI local bus and
the VMEchip2 ASIC. Table 2-5 shows the mapping of onboard resources
from the point of view of the VME2PCI.