Gettemp(); Gettemp() Example - Intel BX80619I73820 Design Manual

7.1.2.3

GetTemp()

The GetTemp() command is used to retrieve the maximum die temperature from a
target PECI address. The temperature is used by the external thermal management
system to regulate the temperature on the die. The data is returned as a negative
value representing the number of degrees centigrade below the maximum processor
junction temperature (T
corresponds to the processor T
which the processor Thermal Control Circuit activates. The actual value that the
thermal management system uses as a control set point (T
negative number below T
issuing a PECI RdPkgConfig() command as described in
RDMSR instruction. T
Chapter 6. Refer to
formatting.
7.1.2.3.1 Command Format
The GetTemp() format is as follows:
Write Length: 0x01
Read Length: 0x02
Command: 0x01
Description: Returns the highest die temperature for addressed processor PECI client.
Figure 7-6. GetTemp()
Byte #
Definition
Example bus transaction for a thermal sensor device located at address 0x30 returning
a value of negative 10 counts is show in
Figure 7-7.

GetTemp() Example

Definition
58
). Note that the maximum PECI temperature value of zero
jmax
jmax
. T
jmax
application to fan speed control management is defined in
CONTROL
Section 7.1.9
0
Write Length
Client Address
Byte
4
FCS
Byte # 0
Byte
0x30
4
0xef
. This also represents the default temperature at
may be extracted from the processor by
CONTROL
for details regarding PECI temperature data
1 2
Read Length
0x01 0x02
5
Temp[7:0] Temp[15:8]
Figure 7-7.
1 2
0x01 0x02
5
0x80
Thermal/Mechanical Specifications and Design Guide
PECI Interface
) is also defined as a
CONTROL
Section 7.1.2.4 or using a
3
Cmd Code
0x01
6 7
FCS
3
0x01
6 7
0xfd 0x4b