
ExCA Compatibilty Registers (Function 0)
116
September 2005
SCPS110
5.7
ExCA Address Window Enable Register
The ExCA address window enable register enables/disables the memory and I/O windows to the 16-bit PC
Card. By default, all windows to the card are disabled. The controller does not acknowledge PCI memory or
I/O cycles to the card if the corresponding enable bit in this register is 0b, regardless of the programming of
the memory or I/O window start/end/offset address registers. See Table 59 for a complete description of the
register contents.
ExCA register offset:
CardBus socket address + 806h;
Card A ExCA offset 06h
Register type:
Read-only, Read/Write
Default value:
00h
BIT NUMBER
7
6
5
4
3
2
1
0
RESET STATE
0
Table 59. ExCA Address Window Enable Register Description
BIT
SIGNAL
TYPE
FUNCTION
7
IOWIN1EN
RW
I/O window 1 enable. Bit 7 enables/disables I/O window 1 for the PC Card. This bit is encoded as:
0 = I/O window 1 disabled (default)
1 = I/O window 1 enabled
6
IOWIN0EN
RW
I/O window 0 enable. Bit 6 enables/disables I/O window 0 for the PC Card. This bit is encoded as:
0 = I/O window 0 disabled (default)
1 = I/O window 0 enabled
5
RSVD
R
Reserved. Bit 5 returns 0b when read.
4
MEMWIN4EN
RW
Memory window 4 enable. Bit 4 enables/disables memory window 4 for the PC Card. This bit is
encoded as:
0 = Memory window 4 disabled (default)
1 = Memory window 4 enabled
3
MEMWIN3EN
RW
Memory window 3 enable. Bit 3 enables/disables memory window 3 for the PC Card. This bit is
encoded as:
0 = Memory window 3 disabled (default)
1 = Memory window 3 enabled
2
MEMWIN2EN
RW
Memory window 2 enable. Bit 2 enables/disables memory window 2 for the PC Card. This bit is
encoded as:
0 = Memory window 2 disabled (default)
1 = Memory window 2 enabled
1
MEMWIN1EN
RW
Memory window 1 enable. Bit 1 enables/disables memory window 1 for the PC Card. This bit is
encoded as:
0 = Memory window 1 disabled (default)
1 = Memory window 1 enabled
0
MEMWIN0EN
RW
Memory window 0 enable. Bit 0 enables/disables memory window 0 for the PC Card. This bit is
encoded as:
0 = Memory window 0 disabled (default)
1 = Memory window 0 enabled