82801FB Datasheet, PDF (168/786 Pages) Intel Corporation – Intel I/O Controller Hub 6 (ICH6) Family

Functional Description
5.14.10.1 Write Only Registers with Read Paths in
ALT Access Mode
The registers described in Table 5-35 have read paths in ALT access mode. The access number
field in the table indicates which register will be returned per access to that port.
Table 5-35. Write Only Registers with Read Paths in ALT Access Mode (Sheet 1 of 2)
Restore Data
Restore Data
I/O
Addr
# of
Rds
Access
Data
00h 2
1 DMA Chan 0 base address low byte
2 DMA Chan 0 base address high byte
01h 2
1 DMA Chan 0 base count low byte
2 DMA Chan 0 base count high byte
02h 2
1 DMA Chan 1 base address low byte
2 DMA Chan 1 base address high byte
03h 2
1 DMA Chan 1 base count low byte
2 DMA Chan 1 base count high byte
I/O
Addr
# of
Rds
Access
Data
40h 7
1 Timer Counter 0 status, bits [5:0]
2 Timer Counter 0 base count low byte
3
Timer Counter 0 base count high
byte
4 Timer Counter 1 base count low byte
5
Timer Counter 1 base count high
byte
6 Timer Counter 2 base count low byte
7
Timer Counter 2 base count high
byte
41h 1
Timer Counter 1 status, bits [5:0]
04h 2
05h 2
06h 2
07h 2
08h 6
1
DMA Chan 2 base address low byte
42h 1
2 DMA Chan 2 base address high byte 70h 1
1 DMA Chan 2 base count low byte
2 DMA Chan 2 base count high byte
C4h 2
1 DMA Chan 3 base address low byte
C6h 2
2 DMA Chan 3 base address high byte
1 DMA Chan 3 base count low byte
2 DMA Chan 3 base count high byte
1
DMA Chan 0–3 Command²
2 DMA Chan 0–3 Request
C8h 2
CAh 2
3
DMA Chan 0 Mode:
Bits(1:0) = 00
4
DMA Chan 1 Mode:
Bits(1:0) = 01
CCh 2
5
DMA Chan 2 Mode:
Bits(1:0) = 10
6 DMA Chan 3 Mode: Bits(1:0) = 11.
CEh 2
Timer Counter 2 status, bits [5:0]
Bit 7 = NMI Enable,
Bits [6:0] = RTC Address
1 DMA Chan 5 base address low byte
2 DMA Chan 5 base address high byte
1 DMA Chan 5 base count low byte
2 DMA Chan 5 base count high byte
1 DMA Chan 6 base address low byte
2 DMA Chan 6 base address high byte
1 DMA Chan 6 base count low byte
2 DMA Chan 6 base count high byte
1 DMA Chan 7 base address low byte
2 DMA Chan 7 base address high byte
1 DMA Chan 7 base count low byte
2 DMA Chan 7 base count high byte
168
Intel^® I/O Controller Hub 6 (ICH6) Family Datasheet