Intel L3426 BV80605004737AA Data Sheet

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The PECI device address for socket 0 is 30h and socket 1 resides at 31h. Note that each 

address also supports two domains (Domain 0 and Domain 1). For more information on 

PECI domains, refer to the Platform Environment Control Interface Specification. 

PECI command support is covered in detail in the Platform Environment Control 

Interface Specification. Refer to this document for details on supported PECI command 

function and codes.

PECI is largely a fault tolerant interface, including noise immunity and error checking 

improvements over other comparable industry standard interfaces. The PECI client is 

as reliable as the device that it is embedded in, and thus given operating conditions 

that fall under the specification, the PECI will always respond to requests and the 

protocol itself can be relied upon to detect any transmission failures. There are, 

however, certain scenarios where the PECI is know to be unresponsive.

Prior to a power on RESET# and during RESET# assertion, PECI is not ensured to 

provide reliable thermal data. System designs should implement a default power-on 

condition that ensures proper processor operation during the time frame when reliable 

data is not available via PECI. 

To protect platforms from potential operational or safety issues due to an abnormal 

condition on PECI, the Host controller should take action to protect the system from 

possible damaging states. It is recommended that the PECI host controller take 

appropriate action to protect the client processor device if valid temperature readings 

have not been obtained in response to three consecutive gettemp()s or for a one 

second time interval. The host controller may also implement an alert to software in the 

event of a critical or continuous fault condition. 

The error codes supported for the processor GetTemp() command are listed in 

8000h

General sensor error

8002h

Sensor is operational, but has detected a temperature below its operational 
range (underflow).