
ExCA Compatibilty Registers (Function 0)
120
September 2005
SCPS110
5.14 ExCA Memory Windows 04 Start-Address High-Byte Registers
These registers contain the high nibble of the 16-bit memory window start address for memory windows 0,
1, 2, 3, and 4. The lower 4 bits of these registers correspond to bits A23A20 of the start address. In addition,
the memory window data width and wait states are set in this register. See Table 511 for a complete
description of the register contents.
Register:
ExCA memory window 0 start-address high-byte
ExCA register offset:
CardBus Socket Address + 811h: Card A ExCA Offset 11h
Register:
ExCA memory window 1 start-address high-byte
ExCA register offset:
CardBus Socket Address + 819h: Card A ExCA Offset 19h
Register:
ExCA memory window 2 start-address high-byte
ExCA register offset:
CardBus Socket Address + 821h: Card A ExCA Offset 21h
Register:
ExCA memory window 3 start-address high-byte
ExCA register offset:
CardBus Socket Address + 829h: Card A ExCA Offset 29h
Register:
ExCA memory window 4 start-address high-byte
ExCA register offset:
CardBus Socket Address + 831h: Card A ExCA Offset 31h
Register type:
Read/Write
Default value:
00h
BIT NUMBER
7
6
5
4
3
2
1
0
RESET STATE
0
Table 511. ExCA Memory Windows 04 Start-Address High-Byte Registers Description
BIT
SIGNAL
TYPE
FUNCTION
7
DATASIZE
RW
This bit controls the memory window data width. This bit is encoded as:
0 = Window data width is 8 bits (default)
1 = Window data width is 16 bits
6
ZEROWAIT
RW
Zero wait-state. This bit controls the memory window wait state for 8- and 16-bit accesses. This wait-state
timing emulates the ISA wait state used by the 82365SL-DF. This bit is encoded as:
0 = 8- and 16-bit cycles have standard length (default).
1 = 8-bit cycles reduced to equivalent of three ISA cycles
16-bit cycles reduced to the equivalent of two ISA cycles
54
SCRATCH
RW
Scratch pad bits. These bits have no effect on memory window operation.
30
STAHN
RW
Start address high-nibble. These bits represent the upper address bits A23A20 of the memory window
start address.
5.15 ExCA Memory Windows 04 End-Address Low-Byte Registers
These registers contain the low byte of the 16-bit memory window end address for memory windows 0, 1, 2,
3, and 4. The 8 bits of these registers correspond to bits A19A12 of the end address.
Register:
ExCA memory window 0 end-address low-byte
ExCA register offset:
CardBus Socket Address + 812h: Card A ExCA Offset 12h
Register:
ExCA memory window 1 end-address low-byte
ExCA register offset:
CardBus Socket Address + 81Ah: Card A ExCA Offset 1Ah
Register:
ExCA memory window 2 end-address low-byte
ExCA register offset:
CardBus Socket Address + 822h: Card A ExCA Offset 22h
Register:
ExCA memory window 3 end-address low-byte
ExCA register offset:
CardBus Socket Address + 82Ah: Card A ExCA Offset 2Ah
Register:
ExCA memory window 4 end-address low-byte
ExCA register offset:
CardBus Socket Address + 832h: Card A ExCA Offset 32h
Register type:
Default value:
00h
BIT NUMBER
7
6
5
4
3
2
1
0
RESET STATE
0