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AMD Geode SC3200 User Manual

Page 281

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AMD Geode™ SC3200 Processor Data Book

281

Core Logic Module - X-Bus Expansion Interface - Function 5

32581C

Offset 04h-07h

I/O Control Register 2 (R/W)

Reset Value: 00000002h

31:2

Reserved. Write as read.

1

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.

0

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).

Offset 08h-0Bh

I/O Control Register 3 (R/W)

Reset Value: 00009000h

31:16

Reserved. Write as read.

15:13

IO_USB_XCVR_VADJ (USB Voltage Adjustment Connection). These bits connect to the voltage adjustment interface on
the three USB transceivers. Default = 100.

12:8

IO_USB_XCVT_CADJ (USB Current Adjustment). These bits connect to the current adjustment interface on the three
USB transceivers. Default = 10000.

7

IO_TEST_PORT_EN (Debug Test Port Enable).

0: Disable

1: Enable

6:0

IO_TEST_PORT_REG (Debug Port Pointer). These bits are used to point to the 16-bit slice of the test port bus.

Table 6-40. F5BAR0+I/O Offset: X-Bus Expansion Registers (Continued)

Bit

Description