Peci Specifications; Peci Device Address; Peci Command Support; Peci Fault Handling Requirements - Intel E3300 Datasheet

Thermal Specifications and Design Considerations
5.3.2

PECI Specifications

5.3.2.1

PECI Device Address

The PECI register resides at address 30h.
5.3.2.2

PECI Command Support

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.
5.3.2.3

PECI Fault Handling Requirements

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 assured 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 using 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 damage. 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.
5.3.2.4

PECI GetTemp0() Error Code Support

The error codes supported for the processor GetTemp() command are listed in
Table 27:
Table 27.

GetTemp0() Error Codes

Error Code
8000h
8002h
Datasheet
General sensor error
Sensor is operational, but has detected a temperature below its operational
range (underflow)
Description
§ §
83