5.21 ExCA I/O Windows 0 and 1 Offset-Address Low-Byte Registers

These registers contain the low byte of the 16-bit I/O window offset address for I/O windows 0 and 1. The 8 bits of these registers correspond to the lower 8 bits of the offset address, and bit 0 is always 0.

Bit

7

6

5

4

3

2

 

1

0

 

 

 

 

 

 

 

 

 

 

Name

 

 

ExCA I/O windows 0 and 1 offset-address low-byte

 

 

 

 

 

 

 

 

 

 

 

Type

RW

RW

RW

RW

RW

RW

 

RW

R

 

 

 

 

 

 

 

 

 

 

Default

0

0

0

0

0

0

 

0

0

 

Register:

ExCA I/O window 0 offset-address low-byte

 

 

 

 

 

Offset:

CardBus Socket Address + 836h:

Card A ExCA Offset 36h

 

 

 

 

 

 

 

Card B ExCA Offset 76h

 

 

 

Register:

ExCA I/O window 1 offset-address low-byte

 

 

 

 

 

Offset:

CardBus Socket Address + 838h:

Card A ExCA Offset 38h

 

 

 

 

 

 

 

Card B ExCA Offset 78h

 

 

 

Type:

Read/Write, Read-only

 

 

 

 

 

 

 

Default:

00h

 

 

 

 

 

 

 

5.22 ExCA I/O Windows 0 and 1 Offset-Address High-Byte Registers

These registers contain the high byte of the 16-bit I/O window offset address for I/O windows 0 and 1. The 8 bits of these registers correspond to the upper 8 bits of the offset address.

Bit

7

6

5

4

3

2

 

1

0

 

 

 

 

 

 

 

 

 

 

Name

 

 

ExCA I/O windows 0 and 1 offset-address high-byte

 

 

 

 

 

 

 

 

 

 

 

Type

RW

RW

RW

RW

RW

RW

 

RW

RW

 

 

 

 

 

 

 

 

 

 

Default

0

0

0

0

0

0

 

0

0

 

Register:

ExCA I/O window 0 offset-address high-byte

 

 

 

 

 

Offset:

CardBus Socket Address + 837h:

Card A ExCA Offset 37h

 

 

 

 

 

 

 

Card B ExCA Offset 77h

 

 

 

Register:

ExCA I/O window 1 offset-address high-byte

 

 

 

 

 

Offset:

CardBus Socket Address + 839h:

Card A ExCA Offset 39h

 

 

 

 

 

 

 

Card B ExCA Offset 79h

 

 

 

Type:

Read/Write

 

 

 

 

 

 

 

 

Default:

00h

 

 

 

 

 

 

 

5−23

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Texas Instruments PCI7421, PCI7411, PCI7611, PCI7621 manual ExCA I/O Windows 0 and 1 Offset-Address Low-Byte Registers