5.16 ExCA Memory Windows 0−4 End-Address High-Byte Registers

These registers contain the high nibble of the 16-bit memory window end address for memory windows 0, 1, 2, 3, and 4. The lower 4 bits of these registers correspond to bits A23−A20 of the end address. In addition, the memory window wait states are set in this register. See Table 5−12 for a complete description of the register contents.

Bit

7

 

 

6

 

5

4

3

 

2

 

1

 

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Name

 

 

 

 

 

 

ExCA memory windows 0−4 end-address high-byte

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Type

RW

 

 

RW

 

R

R

RW

 

RW

 

RW

 

RW

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Default

0

 

 

0

 

0

0

0

 

0

 

0

 

0

 

Register:

 

ExCA memory window 0 end-address high-byte

 

 

 

 

 

 

Offset:

 

CardBus Socket Address + 813h:

Card A ExCA Offset 13h

 

 

 

 

 

 

 

 

 

 

 

 

Card B ExCA Offset 53h

 

 

 

 

Register:

 

ExCA memory window 1 end-address high-byte

 

 

 

 

 

 

Offset:

 

CardBus Socket Address + 81Bh:

Card A ExCA Offset 1Bh

 

 

 

 

 

 

 

 

 

 

 

 

Card B ExCA Offset 5Bh

 

 

 

 

Register:

 

ExCA memory window 2 end-address high-byte

 

 

 

 

 

 

Offset:

 

CardBus Socket Address + 823h:

Card A ExCA Offset 23h

 

 

 

 

 

 

 

 

 

 

 

 

Card B ExCA Offset 63h

 

 

 

 

Register:

 

ExCA memory window 3 end-address high-byte

 

 

 

 

 

 

Offset:

 

CardBus Socket Address + 82Bh:

Card A ExCA Offset 2Bh

 

 

 

 

 

 

 

 

 

 

 

 

Card B ExCA Offset 6Bh

 

 

 

 

Register:

 

ExCA Memory window 4 end-address high-byte

 

 

 

 

 

 

Offset:

 

CardBus Socket Address + 833h:

Card A ExCA Offset 33h

 

 

 

 

 

 

 

 

 

 

 

 

Card B ExCA Offset 73h

 

 

 

 

Type:

 

Read/Write, Read-only

 

 

 

 

 

 

 

 

 

Default:

 

00h

 

 

 

 

 

 

 

 

 

 

Table 5−12. ExCA Memory Windows 0−4 End-Address High-Byte Registers Description

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

BIT

SIGNAL

TYPE

 

 

 

 

 

FUNCTION

 

 

 

 

 

 

 

 

 

 

 

7−6

MEMWS

 

RW

 

Wait state. These bits specify the number of equivalent ISA wait states to be added to 16-bit memory

 

 

accesses. The number of wait states added is equal to the binary value of these 2 bits.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5−4

RSVD

 

R

Reserved. These bits return 0s when read. Writes have no effect.

 

 

 

 

 

 

 

 

 

3−0

ENDHN

 

RW

 

End-address high nibble. These bits represent the upper address bits A23−A20 of the memory window end

 

 

address.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5−18

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Image 146
Texas Instruments PCI7621, PCI7411, PCI7611, PCI7421 manual ExCA Memory Windows 0−4 End-Address High-Byte Registers