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286
Revision 3.0
G
Core Logic Module
(Continued)
5.4.5.1
F5 Index 10h, Base Address Register 0 (F5BAR0) set the
base address that allows PCI access to additional I/O Con-
X-Bus Expansion Support Registers
trol support registers. Table 5-40 shows the support regis-
ters accessed through F5BAR0.
Table 5-40. F5BAR0+I/O Offset: X-Bus Expansion Registers
Bit
Description
Offset 00h-03h
I/O Control Register 1 (R/W)
Reset Value: 010C0007h
31:28
27
Reserved.
IO_ENABLE_SIO_IR (Enable Integrated SIO Infrared).
0: Disable.
1: Enable.
IO_SIOCFG_IN (Integrated SIO Input Configuration).
These two bits can be used to disable the integrated SIO totally or
limit/control the base address.
00: Integrated SIO disable.
01: Integrated SIO configuration access disable.
10: Integrated SIO base address 02Eh/02Fh enable.
11: Integrated SIO base address 015Ch/015Dh enable.
IO_ENABLE_SIO_DRIVING_ISA_BUS (Enable Integrated SIO ISA Bus Control).
Allow the integrated SIO to drive the
internal ISA bus.
0: Disable.
1: Enable. (Default)
Reserved.
Set to 0.
IO_USB_SMI_PWM_EN (USB Internal SMI).
Route USB-generated SMI to SMI Status Register in F1BAR0+I/O Offset
00h/02h[14].
0: Disable.
1: Enable.
IO_USB_SMI_EN (USB SMI Configuration).
Allow USB-generated SMIs.
0: Disable
1: Enable.
If bits 19 and 20 are enabled, the SMI generated by the USB is reported via the Top Level SMI status register at
F1BAR0+I/O Offset 00h/02h[14].
If only bit 19 is enabled, the USB can generate an SMI but there is no status reporting.
IO_USB_PCI_EN (USB).
Enables USB ports.
0: Disable.
1: Enable.
Reserved.
26:25
24
23:21
20
19
18
17:0
Offset 04h-07h
I/O Control Register 2 (R/W)
Reset Value: 00000002h
31:2
1
Reserved.
Write as read.
Video Processor Access Enable.
Allows access to video processor using F4BAR0.
0: Disable.
1: Enable. (Default)
Note:
This bit is readable after the register (F5BAR0+Offset 04h) has been written once.
IO_STRAP_IDSEL_SELECT (IDSEL Strap Override).
0: IDSEL: AD28 for Chipset Register Space (F0-F5), AD29 for USB Register Space (PCIUSB).
1: IDSEL: AD26 for Chipset Register Space (F0-F5), AD27 for USB Register Space (PCIUSB).
0