Mpc slave offset/attribute (3) registers, Mpc slave offset/attribute (3) registers -46 – Motorola MVME2300 Series User Manual

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2

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 the section on

Generating PCI Memory and I/O

Cycles

. 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. 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

RE
N

WE

N

WP

E

N

IOM

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

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