5.8 ExCA I/O Window Control Register
The ExCA I/O window control register contains parameters related to I/O window sizing and cycle timing. See
Table 5−10 for a complete description of the register contents.
Bit
7
6
5
4
3
2
1
0
Name
Type
Default
ExCA I/O window control
RW
0
RW
0
RW
0
RW
0
RW
0
RW
0
RW
0
RW
0
Register:
Type:
ExCA I/O window control
Read/Write
Offset:
CardBus socket address + 807h: Card A ExCA offset 07h
Card B ExCA offset 47h
00h
Default:
SIGNAL
Table 5−10. ExCA I/O Window Control Register Description
BIT
TYPE
FUNCTION
I/O window 1 wait state. Bit 7 controls the I/O window 1 wait state for 16-bit I/O accesses. Bit 7 has no effect
on 8-bit accesses. This wait-state timing emulates the ISA wait state used by the Intel 82365SL-DF. This
bit is encoded as:
7
WAITSTATE1
RW
0 = 16-bit cycles have standard length (default).
1 = 16-bit cycles are extended by one equivalent ISA wait state.
I/O window 1 zero wait state. Bit 6 controls the I/O window 1 wait state for 8-bit I/O accesses. Bit 6 has
no effect on 16-bit accesses. This wait-state timing emulates the ISA wait state used by the Intel
82365SL-DF. This bit is encoded as:
6
ZEROWS1
RW
0 = 8-bit cycles have standard length (default).
1 = 8-bit cycles are reduced to equivalent of three ISA cycles.
I/O window 1 IOIS16 source. Bit 5 controls the I/O window 1 automatic data-sizing feature that uses IOIS16
from the PC Card to determine the data width of the I/O data transfer. This bit is encoded as:
0 = Window data width determined by DATASIZE1, bit 4 (default).
5
4
IOSIS16W1
DATASIZE1
RW
RW
1 = Window data width determined by IOIS16.
I/O window 1 data size. Bit 4 controls the I/O window 1 data size. Bit 4 is ignored if bit 5 (IOSIS16W1) is
set. This bit is encoded as:
0 = Window data width is 8 bits (default).
1 = Window data width is 16 bits.
I/O window 0 wait state. Bit 3 controls the I/O window 0 wait state for 16-bit I/O accesses. Bit 3 has no effect
on 8-bit accesses. This wait-state timing emulates the ISA wait state used by the Intel 82365SL-DF. This
bit is encoded as:
3
2
WAITSTATE0
ZEROWS0
RW
RW
0 = 16-bit cycles have standard length (default).
1 = 16-bit cycles are extended by one equivalent ISA wait state.
I/O window 0 zero wait state. Bit 2 controls the I/O window 0 wait state for 8-bit I/O accesses. Bit 2 has
no effect on 16-bit accesses. This wait-state timing emulates the ISA wait state used by the Intel
82365SL-DF. This bit is encoded as:
0 = 8-bit cycles have standard length (default).
1 = 8-bit cycles are reduced to equivalent of three ISA cycles.
I/O window 0 IOIS16 source. Bit 1 controls the I/O window 0 automatic data sizing feature that uses IOIS16
from the PC Card to determine the data width of the I/O data transfer. This bit is encoded as:
0 = Window data width is determined by DATASIZE0, bit 0 (default).
1
0
IOSIS16W0
DATASIZE0
RW
RW
1 = Window data width is determined by IOIS16.
I/O window 0 data size. Bit 0 controls the I/O window 0 data size. Bit 0 is ignored if bit 1 (IOSIS16W0) is
set. This bit is encoded as:
0 = Window data width is 8 bits (default).
1 = Window data width is 16 bits.
5−12
TI [ TEXAS INSTRUMENTS ]
