HP Vectra VL800, Техническое справочное руководство

Страница: 64 / 147

64
3 System Board
The Input/Output Controller Hub 2 (82801BA)
ICH2 SMBus Master
Controller
The ICH2 provides a processor-to-SMBus controller. All access performed to
the SMBus is done through the ICH2 SMBus interface. Typically, the
processor has access to all the devices connected to the SMBus.
RIMM Sockets
Each RIMM socket is connected to the SMBus. The 168-pin RIMM modules
include a 256 byte I
2
C Serial EEPROM. The first 128 bytes contain general
information, including the RDRAM chip manufacturer’s name, RIMM speed
rating, RIMM type, etc. The second 128 bytes of the Serial EEPROM can be
used to store data online.
Serial EEPROM
This is the non-volatile memory which holds the default values for the CMOS
memory (in the event of battery failure).When installing a new system
board, the Serial EEPROM will have a blank serial number field. This will be
detected automatically by the BIOS, which will then prompt the user for the
serial number which is printed on the identification label on the back of the
PC.
The computer uses 16KBytes of Serial EEPROM implemented within one
chip. Serial EEPROM is ROM in which one byte at a time can be returned to
its unprogrammed state by the application of appropriate electrical signals.
In effect, it can be made to behave like very slow, non-volatile RAM. It is
used for storing the tatoo string, the serial number, and the parameter
settings for the
Setup
program as well as hardware monitoring firmware.