Intel 9130M NE80567KF0288M User Manual

104

Intel Itanium processor 9300 series supports a Scratch EEPROM section, which may be 
used for other data at the system vendor’s discretion. The data in this EEPROM, once 
programmed, can be write-protected by asserting the active-high SM_WP signal. This 
signal has a weak pull-down (10 k) to allow the EEPROM to be programmed in 

systems with no implementation of this signal. The Scratch EEPROM resides in the 
upper half of the memory component (addresses 80 - FFh). The lower half comprises 
the Processor Information ROM (addresses 00 - 7Fh), which is permanently write-
protected.

The PIROM responds to two SMBus packet types: Read Byte and Write Byte. However, 
since the PIROM is write-protected, it will acknowledge a Write Byte command but 
ignores the data. The Scratch EEPROM responds to Read Byte and Write Byte 
commands. 

 

illustrates the Read Byte command. 

 

illustrates the 

Write Byte command. 

In the tables, ‘S’ represents the SMBus start bit, ‘P’ represents a stop bit, ‘A’ represents 
an acknowledge (ACK), and ‘///’ represents a negative acknowledge (NACK). The 
shaded bits are transmitted by the PIROM or Scratch EEPROM, and the bits that aren’t 
shaded are transmitted by the SMBus host controller. In the tables, the data addresses 
indicate 8 bits.

The SMBus host controller should transmit 8 bits with the most significant bit indicating 
which section of the EEPROM is to be addressed: the PIROM (MSB = 0) or the Scratch 
EEPROM (MSB = 1).

120

78h

Package Feature Flags

hex 

all other are reserved

Bit[3] = THERMALERT_N 

threshold values present

Bit[2] = SCRATCH EEPROM 

present

Bit[1] = Core VID present

where a 1 indicates valid 

data

Flag = 0x000E

78h = 0x0E
79h = 0x00

121

79h

122

7Ah

RESERVED

hex

Reserved for future use

7Ah = 0x00

123

7Bh

Number of Devices in TAP 
Chain

hex

Bits [7:4] Number Devices 
in processor TAP chain
Bits [3:0] Reserved

5 devices for TKW = 0x50

124

7Ch

Checksum

hex

Add up by byte and take 
2's compliment

125

7Dh

RESERVED

hex

Reserved for future use

7Dh = 0x00

7Eh = 0x00
7Fh = 0x00

126

7Eh

127

7Fh