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Raven PCI Host Bridge & Multi-Processor Interrupt Controller Chip
2
WEN
Write Enable. If set, the corresponding MPC slave is
enabled for write transactions.
WPEN
Write Post Enable. If set, write posting is enabled for the
corresponding MPC slave.
MEM
PCI Memory Cycle. If set, the corresponding MPC slave
will generate transfers to or from PCI memory space.
When clear, the corresponding MPC slave will generate
transfers to or from PCI I/O space using the addressing
mode defined by the IOM field.
IOM
PCI I/O Mode. If set, the corresponding MPC slave will
generate PCI I/O cycles using spread addressing as
defined in
. When
clear, the corresponding MPC slave will generate PCI I/O
cycles using contiguous addressing. This field only has
meaning when the MEM bit is clear.
MPC Slave Offset/Attribute (3) Registers
MSOFF3
MPC Slave Offset. This register contains a 16-bit offset
that is added to the upper 16 bits of the MPC address to
determine the PCI address used for transfers from the
MPC bus to PCI. This offset allows PCI resources to
reside at addresses that would not normally be visible
from the MPC bus. It is initialized to $8000 to facilitate a
zero-based access to PCI space.
Address
MSOFF3/MSATT3 - $FEFF005C
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
MSOFF3
MSATT3
REN
WE
N
W
PEN
IO
M
Operation
R/W
R
R/W
R/W
R
R/W
R
R
R
R/W
Reset
$8000
$00
1
1
0
0
0
0
0
0