Intel 1.40 GHz YA80543KC0174M User Manual

Product codes
YA80543KC0174M
Page of 108
88
Datasheet 
System Management Feature Specifications
All of the commands are for reading or writing registers in the thermal sensor except the one-shot 
command (OSHT). The one-shot command forces the immediate start of a new voltage-to-
temperature conversion cycle. If a conversion is in progress when the one-shot command is 
received, then the command is ignored. If the thermal sensing device is in standby mode when the 
one-shot command is received, a conversion is performed and the sensor returns to standby mode. 
If the thermal sensor is in auto-convert mode and is between conversions, then the conversion rate 
timer resets, and the next automatic conversion takes place after a full delay elapses. Please refer to 
 for further detail on standby and auto-convert modes.
The default command after reset is the reserved value (00h). After reset, receive byte packets will 
return invalid data until another command is sent to the thermal sensing device.
6.7
Thermal Sensing Device Registers
The system management software can configure and control the thermal sensor by writing to and 
interacting with different registers in the thermal sensor. These registers include a thermal 
reference register, two thermal limit registers, a status register, a configuration register, a 
conversion rate register, and other reserved registers. The following subsections describe the 
registers in detail.
6.7.1
Thermal Reference Registers
The processor core and thermal sensing device internal thermal reference registers contain the 
thermal reference value of the thermal sensing device and the processor core thermal diodes. This 
value ranges from +127 to –128 decimal and is expressed as a two’s complement, eight-bit number. 
These registers are saturating, that is, values above 127 are represented at 127 decimal, and values 
below –128 are represented as –128 decimal.
Table 6-13. Command Byte Bit Assignment
Register
Command
Reset State
Function
RESERVED
00h
N/A
Reserved for future use.
RRT
01h
N/A
Read processor core thermal data.
RS
02h
N/A
Read status byte (flags, busy signal).
RC
03h
0000 0000
Read configuration byte.
RCR
04h
0000 0010
Read conversion rate byte.
RESERVED
05h
0111 1111
Reserved for future use.
RESERVED
06h
1100 1001
Reserved for future use.
RRHL
07h
0111 1111
Read processor core thermal diode T
HIGH
 limit.
RRLL
08h
1100 1001
Read processor core thermal diode T
LOW
 limit.
WC
09h
N/A
Write configuration byte.
WCR
0Ah
N/A
Write conversion rate byte.
RESERVED
0Bh
N/A
Reserved for future use.
RESERVED
0Ch
N/A
Reserved for future use.
WRHL
0Dh
N/A
Write processor core thermal diode T
HIGH
 limit.
WRLL
0Eh
N/A
Write processor core thermal diode T
LOW
 limit.
OSHT
0Fh
N/A
One shot command (use send byte packet).
RESERVED
10h – FFh
N/A
Reserved for future use.