Register Description

R

3.6.8MLT1—Master Latency Timer Register (Device 1)

Address Offset:

0Dh

Default Value:

00h

Access:

R/W

Size:

8 bits

This functionality is not applicable. It is described here since these bits should be implemented as a read/write to prevent standard PCI-PCI bridge configuration software from getting “confused”.

Bit

Description

 

 

7:3

Not applicable but supports read/write operations. (Reads return previously written data.)

 

 

2:0

Reserved.

 

 

3.6.9HDR1—Header Type Register (Device 1)

Offset:

0Eh

Default:

01h

Access:

RO

Size:

8 bits

This register identifies the header layout of the configuration space.

Bit

Descriptions

 

 

7:0

This read only field always returns 01h when read. Writes have no effect.

 

 

3.6.10PBUSN1—Primary Bus Number Register (Device 1)

Offset:

18h

Default:

00h

Access:

RO

Size:

8 bits

This register identifies that “virtual” PCI-PCI Bridge is connected to bus #0.

Bit

Descriptions

 

 

7:0

Bus Number. Hardwired to 0.

 

 

Intel® 82845 MCH for SDR Datasheet

85

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Image 85
Intel 845 manual 8 MLT1-Master Latency Timer Register Device, 9 HDR1-Header Type Register Device