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Raven PCI Host Bridge & Multi-Processor Interrupt Controller
2
MSOFF3 PPC Slave Offset. This register contains a 16-bit offset that is
added to the upper 16 bits of the PPC address to determine the PCI address
used for transfers from the PPC bus to PCI. This offset allows PCI
resources to reside at addresses that would not normally be visible from the
PPC bus. It is initialized to $8000 to facilitate a zero-based access to PCI
space.
REN Read Enable. If set, the corresponding PPC slave is enabled for read
transactions.
WEN Write Enable. If set, the corresponding PPC slave is enabled for
write transactions.
WPEN Write Post Enable. If set, write posting is enabled for the
corresponding PPC slave.
IOM PCI I/O Mode. If set, the corresponding PPC slave will generate
PCI I/O cycles using spread addressing as defined in the section on
Generating PCI Memory and I/O Cycles
. When clear, the corresponding
PPC slave will generate PCI I/O cycles using contiguous addressing.
General Purpose Registers
These general purpose read/write registers are provided for inter-process
message passing or general purpose storage. They do not control any
hardware.
Address
GPREG0 (Upper) - $FEFF0070
GPREG0 (Lower) - $FEFF0074
GPREG1 (Upper) - $FEFF0078
GPREG1 (Lower) - $FEFF007C
Bit
0 1 2 3 4 5 6 7 8 9
1
0
1
1
1
2
1
3
1
4
1
5
1
6
1
7
1
8
1
9
2
0
2
1
2
2
2
3
2
4
2
5
2
6
2
7
2
8
2
9
3
0
3
1
Name
GPREGx
Operatio
n
R/W
Reset
$00000000