Field Name Bits Default Description
OHCI_2_enable 3 1b Set to 1 to enable OHCI_2
OHCI_3_enable 4 1b Set to 1 to enable OHCI_3
OHCI_4_enable 5 1b Set to 1 to enable OHCI_4
Reserved 7:6 00b
UsbEnable register
SeriallrqControl- RW - 8 bits - [PCI_Reg: 69h] Field Name Bits Default Description
NumStartBits 1:0 00b This field defines the number of clocks in the start frame.
Start Frame Width = 4 + 2 * NumStartBits
NumSerIrqBits 5:2 0h Total number of serial IRQ's = 17 + NumSerIrqbits
0 - 17 serial IRQ's (15 IRQ, SMI#, + IOCHK#)
1 - 18 serial IRQ's (15 IRQ, SMI#, IOCHK#, INTA#)
...
15 - 32 serial IRQ's
The SB600 serial IRQ can support 15 IRQ#, SMI#, IOCHK#,
INTA#, INTB#, INTC#, and INTD#.
When serial SMI# is used, BIOS will need to check SIO (or
device that generates serial SMI#) for status.
SerIrqMode 6 0b 0 - Continuous mode
1 - Active (quiet) mode
SerialIrqEnable 7 0b Setting this bit to 1 enable the serial IRQ function
SeriallrqControl register
RTCProtect- RW - 8 bits - [PCI_Reg: 6Ah] Field Name Bits Default Description
RTCProtect38_3F 0 0b When set, RTC RAM index 38:3Fh will be locked from
read/write. This bit can only be written once.
RTCProtectF0_FF 1 0b When set, RTC RAM index F0:FFh will be locked from
read/write. This bit can only be written once.
RTCProtectE0_EF 2 0b When set, RTC RAM index E0:EFh will be locked from
read/write. This bit can only be written once.
RTCProtectD0_DF 3 0b When set, RTC RAM index D0:DFh will be locked from
read/write. This bit can only be written once.
RTCProtectC0_CF 4 0b When set, RTC RAM index C0:CFh will be locked from
read/write. This bit can only be written once.
Reserved 7:5 000b
RTCProtect register
USB Reset- RW - 8 bits - [PCI_Reg: 6Bh] Field Name Bits Default Description
Force Reset to USB Host
Controllers
4:0 00h These are software control bits that force the reset of the USB
host controllers.
Force USB Port PHY
Power Down
5 0b Forces USB PHY into power down mode.
Force PHY PLL Power
Down
6 0b Forces USB PHY PLL into power down mode.
Force USB Port PHY
Reset
7 0b Forces USB PHY reset.
USB Reset register