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Introduction
1-2
82801AA and 82801AB Datasheet
Chapter 5. Functional Description
Chapter 5 provides a detailed description of the functions in the ICH. All functions in this datasheet
are abbreviated using the following nomenclature; Device:Function. This manual abbreviates
devices with D30 and D31 and functions with F0, F1, F2, F3, F4, F5 and F6. For example, Device
31 Function 5 is abbreviated as D31:F5.
Chapter 6. Register Memory and I/O Address Maps
Chapter 6 provides an overview of the registers, fixed I/O ranges, variable I/O ranges, and memory
ranges decoded by the ICH.
Chapter 7. Hub Interface to PCI Bridge Registers
Chapter 7 provides a detail description of all registers that reside in the Hub Link to PCI bridge.
This bridge resides at Device 30, Function 0 (D30:F0).
Chapter 8. LPC Bridge Registers
Chapter 8 provides a detail description of all registers that reside in the LPC bridge. This bridge
resides at Device 31, Function 0 (D31:F0). This function contains registers for many different units
within the ICH including DMA, Timers, Interrupts, Processor Interface, GPIO, Power
Management, System Management and RTC.
Chapter 9. IDE Controller Registers
Chapter 9 provides a detail description of all registers that reside in the IDE controller. This
controller resides at Device 31, Function 1 (D31:F1).
Chapter 10. USB Controller Registers
Chapter 10 provides a detail description of all registers that reside in the USB controller. This
controller resides at Device 31, Function 2 (D31:F2).
Chapter 11. SMBus Controller Registers
Chapter 11 provides a detail description of all registers that reside in the SMBus controller. This
controller resides at Device 31, Function 3 (D31:F3).
Chapter 12. AC’97 Audio Controller Registers
Chapter 12 provides a detail description of all registers that reside in the audio controller. This
controller resides at Device 31, Function 5 (D31:F5). Note that this section of the EDS does not
include the native audio mixer registers. Accesses to the mixer registers are forwarded over the
AC-link to the codec where the registers reside.
Chapter 13. AC’97 Modem Controller Registers
Chapter 13 provides a detail description of all registers that reside in the modem controller. This
controller resides at Device 31, Function 6 (D31:F6). Note that this section of the EDS does not
include the modem mixer registers. Accesses to the mixer registers are forwarded over the AC-link
to the codec where the registers reside.
Chapter 14. Electrical Characteristics
Chapter 14 provides all AC and DC characteristics including detailed timing diagrams.
Chapter 15. Pinout and Package Information
Chapter 15 provides a table of each signal and its ball assignment in the 241 BGA package. A
footprint of the ballout is also provided. This chapter also provides the physical dimensions and
characteristics of the 241 BGA package.
Chapter 16. Testability
Chapter 17 provides details about the implementation of two test modes provided in the ICH;
NAND Tree and High-Z.
Appendix A. Register Index
Appendix A provides a list of registers and the location within the datasheet where the register
description can be found.
Appendix B. Register Bit Index
Appendix B provides an alphabetical list of the register bits (by bit name) and the location within
the datasheet where the register bit description can be found.