2 System Board

FirmWare Hub (82802AB)

The FWH includes two hardware interfaces:

FirmWare Hub interface.

Address/Address Multiplexed (A/A Mux) interface.

The IC (Interface Configuration) pin on the FWH provides the control between these interfaces. The interface mode needs to be selected prior to power-up or before return from reset (RST# or INIT# low to high transition).

The FWH interface works with the ICH2 during system operation, while the A/A Mux interface is designed as a programming interface for component pre-programming.

An internal CUI (Command User Interface) serves as the control center between the FWH and A/A Mux interfaces, and internal operation of the non-volatile memory. A valid command sequence written to the CUI initiates device automation. An internal WSM (Write State Machine) automatically executes the algorithms and timings necessary for block erase and program operations.

55

Page 55
Image 55
HP XU700 manual FirmWare Hub 82802AB