Introduction

The ICH is a highly integrated multifunctional I/O Controller Hub that provides the interface to the PCI Bus and integrates many of the functions needed in today’s PC platforms. The ICH communicates with the host controller over a dedicated hub interface. There are two versions of the ICH (82801AA: ICH and 82801AB: ICH0). This provides added flexibility in designing costeffective system solutions. These devices are pin compatible and are in 241-pin packages.

Intel® 82801AA (I CH) and Intel® 82801AB (ICH0) Features

■ PCI Bus Interface

— Supports PCI at 33 MHz

— Supports PCI Rev 2.2 Specification

— 133 MByte/sec Maximum Throughput

■ Integrated IDE Controller

— Independent Timing of Up to 4 Drives

— Supports Ultra ATA/33 Mode (33 Mbytes/sec)

— PIO Mode 4 Transfers up to 14 Mbytes/s

— Separate IDE Connections for Primary and Secondary Cables

— Implements Write Ping-Pong Buffer for faster write performance

■ USB

— UHCI Implementation With 2 Ports

— Supports Wake-up From Sleeping States S1-S4

— Supports Legacy Keyboard/Mouse Software

— USB Revision 1.1 Compliant

■ AC97 Link for Audio and Telephony CODECs

— AC’97 2.1 Compliant

— 5 Independent Bus Master Logic for PCM In, PCM Out, Mic Input, Modem In, Modem Out

— Separate Independent PCI Functions for Audio and Modem

— Supports wake-up events

■ Interrupt Controller

— Two Cascaded 82C59

— Integrated I/O APIC Capability

— 15 Interrupts Support in 8259 Mode, 24 Supported in I/O APIC Mode.

— Supports Serial Interrupt Protocol

■ Timers Based on 82C54

■ System Timer, Refresh Request, Speaker Tone Output

■ 3.3 V Operation With 5 V Tolerant Buffers for IDE and PCI signals.

■ 241 BGA package

■ GPIO

— TTL, Open-Drain, Inversion

■ Power Management Logic

— ACPI 1.0 Compliant

— Support for APM-Based Legacy Power Management for Non-ACPI Implementations

— ACPI Defined Power States (S1, S3, S4, S5)

— ACPI Power Management Timer

— SMI# Generation

— All Registers Readable/Restorable for Proper Resume from 0 V Suspend States

— PCI PME#

■ Low Pin count (LPC) Interface

— Allows Connection of Legacy ISA and X-Bus Devices such as Super I/O

— Supports Two Master/DMA Devices.

■ Enhanced DMA Controller

— Two Cascaded 8237 DMA Controllers

— PCI DMA: Supports PC/PCI — Includes Two PC/PCI REQ#/GNT# Pairs

— Supports LPC DMA

— Supports DMA Collection Buffer to Provide Type-F DMA Performance for All DMA Channels

■ Real - Time Clock

— 256-byte Battery-Backed CMOS RAM

— Hardware implementation to indicate Century Rollover

■ System TCO Reduction Circuits

— Timers to Generate SMI# and Reset Upon Detection of locked system

— Timers to Detect Improper Processor Reset

— Integrated Processor Frequency Strap Logic

■ SM Bus

— Host Interface Allows Processor to Communicate via SM Bus

— Compatible With Most 2-Wire Components that are Also I2C compatible

■ Supports ISA Bus via External PCI-ISA Bridge

■ Firmware Hub (FWH) Interface

— Master PCI Device Support: up to 6 for the ICH and up to 4 for the ICH0

— The ICH Supports Ultra ATA/66 Mode (66 Mbytes/sec)

■ The 82801AA provides Alert On LAN* Support