AMD Geode SC2200 User Manual

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AMD Geode™ SC2200 Processor Data Book

Core Logic Module - USB Controller Registers - PCIUSB

32580B

Index 10h-13h

Base Address Register- USB_BAR0 (R/W)

Reset Value: 00000000h

31:12

Base Address. POST writes the value of the memory base address to this register.

11:4

Always 0. Indicates that a 4 KB address range is requested.

Always 0. Indicates that there is no support for prefetchable memory.

2:1

Always 0. Indicates that the base register is 32-bits wide and can be placed anywhere in 32-bit memory space.

Always 0. Indicates that the operational registers are mapped into memory space.

Index 14h-2Bh

Reserved

Reset Value: 00h

Index 2Ch-2Dh

Subsystem Vendor ID (RO)

Reset Value: 0E11h

Index 2Eh-2Fh

Subsystem ID (RO)

Reset Value: A0F8h

Index 30h-3Bh

Reserved

Reset Value: 00h

Index 3Ch

Interrupt Line Register (R/W)

Reset Value: 00h

This register identifies the system interrupt controllers to which the device’s interrupt pin is connected. The value of this register is used
by device drivers and has no direct meaning to USB.

Index 3Dh

Interrupt Pin Register (R/W)

Reset Value: 01h

This register selects which interrupt pin the device uses. USB uses INTA# after reset. INTB#, INTC# or INTD# can be selected by writ-
ing 2, 3 or 4, respectively.

Index 3Eh

Min. Grant Register (RO)

Reset Value: 00h

This register specifies how long a burst is needed by the USB, assuming a clock rate of 33 MHz. The value in this register specifies a
period of time in units of 1/4 microsecond.

Index 3Fh

Max. Latency Register (RO)

Reset Value: 50h

This register specifies how often (in units of 1/4 microsecond) the USB needs access to the PCI bus assuming a clock rate of 33 MHz.

Index 40h-43h

ASIC Test Mode Enable Register (R/W)

Reset Value: 000F0000h

Used for internal debug and test purposes only.

Index 44h

ASIC Operational Mode Enable Register (R/W)

Reset Value: 00h

7:1

Write Only. Read as 0s.

Data Buffer Region 16

0: The size of the region for the data buffer is 32 bytes.

1: The size of the region for the data buffer is 16 bytes.

Index 45h-FFh

Reserved

Reset Value: 00h

Table 6-41. PCIUSB: USB PCI Configuration Registers (Continued)

Bit

Description