Thermal Limit Registers; Status Register; Configuration Register; Thermal Sensing Device Status Register - Intel P9500 - Core 2 Duo 2.53 GHz 6M L2 Cache 1066MHz FSB Socket P Mobile Processor Manual

System Management Feature Specifications
6.7.2

Thermal Limit Registers

The thermal sensing device has two thermal limit registers; they define high and low
limits for the processor core thermal diode. The encoding for these registers is the
same as for the thermal reference registers. If the diode thermal value equals or
exceeds one of its limits, then its alarm bit in the status register is triggered. This
indication is also brought out to the processor system bus via the THRMALERT# signal.
6.7.3

Status Register

The status register shown in
thresholds have been exceeded. It also indicates if a conversion is in progress or if an
open circuit has been detected in the processor core thermal diode connection. Once
set, alarm bits stay set until they are cleared by a status register read. A successful
read to the status register will clear any alarm bits that may have been set, unless the
alarm condition persists. Note that the THRMALERT# interrupt signal is latched and is
not automatically cleared when the status flag bit is cleared. The latch is cleared by
sending the Alert Response Address (0001100) on the SMBus.
Table 6-14. Thermal Sensing Device Status Register
Bit
7 (MSB)
6
5
4
3
2
1
0 (LSB)
6.7.4

Configuration Register

The configuration register controls the operating mode (standby vs. auto-convert) of
the thermal sensing device.
If the RUN/STOP bit is set (high) then the thermal sensing device immediately stops
converting and enters standby mode. The thermal sensing device will still perform
analog-to-digital conversions in standby mode when it receives a one-shot command.
If the RUN/STOP bit is clear (low) then the thermal sensor enters auto-conversion
mode. The thermal sensing device starts operating in free running mode, auto-
converting at 0.25 Hz after power-up.
Table 6-15. Thermal Sensing Device Configuration Register
Bit
7 (MSB)
6
5–0
® ®
Dual-Core Intel Itanium Processor 9000 and 9100 Series Datasheet
Table 6-14
Name
BUSY A one indicates that the device's analog to digital converter is busy converting.
RESERVED Reserved for future use.
RESERVED Reserved for future use.
RHIGH A one indicates that the processor core thermal diode high temperature alarm has
been activated.
RLOW A one indicates that the processor core thermal diode low temperature alarm has
been activated.
OPEN A one indicates an open fault in the connection to the processor core diode.
RESERVED Reserved for future use.
RESERVED Reserved for future use.
Table 6-15
Reset
Name
State
RESERVED 0 Reserved for future use.
RUN/STOP 0 Standby mode control bit. If high, the device immediately stops
converting, and enters standby mode. If low, the device converts in
either one-shot or timer mode.
RESERVED 0 Reserved for future use.
indicates which (if any) of the thermal value
Function
shows the format of the configuration register.
Function
89