System Board
FirmWare Hub (82802AB)
Chapter 2
56
FirmWare Hub (82802AB)
The FWH (also known as flash memory) is connected to the LPC bus. It contains 4Mbit
(512KB) of flash memory.
The hardware features of the FWH include:
• Random Number Generator (RNG)
• Five General Purpose Inputs (GPI)
• Register-based block locking
• Hardware-based locking
An integrated combination of logic features and nonvolatile memory:
• Enables better protection for the storage and update of system code and data.
• Adds flexibility through additional GPIs.
• Allows for quicker introduction of security/manageability features.
The following table outlines the available FWH features
Feature Feature
• Platform compatibility:
— Enables security-enhanced platform
infrastructure
— Part of the Intel I840 chipset
• Two configurable interfaces:
— FWH interface for system operation
— Address/Address Multiplexed (A/A Mux)
interface
• FWH interface mode:
— Five signal communication interface supporting
x8 reads and writes
— Register-based read and write protection for each
code/data storage blocks
— Five additional GPIs for system design and
flexibility
— A hardware RNG
— Integrated Command User Interface (CUI) for
requesting access to locking, programming, and
erasing options. Also handles requests for data
residing in status, ID, and block lock registers.
— Operates with 33MHz PCI clock and 3.3V I/O
• 4Mbits of flash memory for system code/data
nonvolatile storage:
— Symmetrically blocked, 64KB memory
sections
— Automated byte program and block erase
through an integrated Write State
Machine (WSM)
• A/A Mux Interface/Mode, supporting:
— 11-pin multiplexed address and 8-pin data I/O
interface
— Fast on-board or out-of-system programming
• Power supply specifications:
— Vcc: 3.3V +/- 0.3V
— Vpp: 3.3V and 12V for fast programming,
80ns
