Intel 460GX, Software Developer’S Manual

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Introduction
1-2 Intel® 460GX Chipset Software Developer’s Manual
1.1.1 Component Overview
Table 1-1 lists the 460GX chipset components.
Table 1-1. Intel® 460GX Chipset Components
Component Name Function
SAC 82461GX
System Address
Controller
Interfaces the address and control portion of the Itanium™ processor
system bus and the memory bus. Acts as a host bridge interface to
peripheral I/O devices through four Expander busses.
SDC 82462GX
System Data path
Controller
Interfaces the data portion of the Itanium processor system bus and
the memory bus.
MAC 82463GX
Memory Address
Controller
Provides the SDRAM RAS/CAS/WE/CS generation as well as
redriving the address to the SDRAMs. It is capable of buffering several
commands from the SAC.
MDC 82464GX
Memory Data path
Controller
Multiplexes the data from the SDRAM to the SDC. On reads, it latches
data from the SDRAM, then transfers the data to the SDC. On writes, it
latches the data from the SDC, then writes the data to the SDRAM.
GXB 82465GX
Graphics Expander
Bridge
Provides the control and data interface for an AGP 4X graphics port.
This device attaches to the SAC via two Expander busses which utilize
a special configuration.
WXB 82466GX
Wide and fast PCI
Expander Bridge
Provides the primary control and data interface for two independent
64-bit, 66 MHz PCI interfaces. This device attaches to the SAC via an
Expander bus.
PXB 82467GX
PCI Expander Bridge
Provides the primary control and data interface for two independent
32-bit, 33-MHz PCI interfaces. These two 32-bit interfaces may
operate together to produce a single 64-bit, 33-MHz interface via a
configuration option. This device attaches to the SAC via an Expander
bus.
IFB 82468GX
I/O and Firmware
Bridge
The IFB is a multi-function PCI device implementing a PCI-to-LPC
bridge function, a PCI IDE function, a Universal Serial Bus Host/Hub
function, an SMBus Interface function, Power Management function
and the Firmware Hub interface.
FWH 82802AC
Firmware Hub 8Mb
The FWH component interfaces to the IFB component and provides
firmware storage and security features. Further FWH information can
be found at http://developer.intel.com/design/chipsets/datasheets or by
ordering document 290658.
PID NEC# UPD66566S1-
016
Programmable
Interrupt Device
The PID is an interrupt controller that provides interrupt steering
functions. The PID contains the logic required to support 8259A mode,
APIC mode, and SAPIC mode interrupt controller operations. The PID
interfaces include a PCI bus interface, an APIC bus interface, a serial
IRQ interface, and an interrupt input interface.