82801DB Datasheet, PDF (386/587 Pages) Intel Corporation – Intel 82801DB I/O Controller Hub 4 (ICH4)

IDE Controller Registers (D31:F1)
10.1.6
10.1.7
10.1.8
PI — Programming Interface Register (IDE—D31:F1)
Address Offset: 09h
Default Value: 8Ah
Attribute: R/W
Size:
8 bits
Bit
Description
7 This read-only bit is a 1 to indicate that the ICH4 supports bus master operation
6:4 Reserved. Will always return 0.
3
SOP_MODE_CAP — RO. This read-only bit is a 1 to indicate that the secondary controller supports
both legacy and native modes.
SOP_MODE_SEL — R/W. This read/write bit determines the mode that the secondary IDE channel
is operating in.
2
0 = Legacy-PCI mode (default)
1 = Native-PCI mode
1
POP_MODE_CAP — RO. This read-only bit is a 1 to indicate that the primary controller supports
both legacy and native modes.
POP_MODE_SEL — R/W. This read/write bit determines the mode that the primary IDE channel is
operating in.
0
0 = Legacy-PCI mode (default)
1 = Native-PCI mode
SCC — Sub Class Code Register (IDE—D31:F1)
Address Offset: 0Ah
Default Value: 01h
Attribute: RO
Size:
8 bits
Bit
Description
Sub Class Code — RO.
7:0
01h = IDE device, in the context of a mass storage device.
BCC — Base Class Code Register (IDE—D31:F1)
Address Offset: 0Bh
Default Value: 01h
Attribute: RO
Size:
8 bits
Bit
Base Class Code — RO.
7:0
01 = Mass storage device
Description
386
Intel^® 82801DB ICH4 Datasheet