NCT6627UD Nuvoton Technology Corporation of America, NCT6627UD Datasheet - Page 49

• Manufacturer Part Number: NCT6627UD
• Manufacturer: Nuvoton Technology Corporation of America

Specifications of NCT6627UD

• Lead Free Status / Rohs Status: Supplier Unconfirmed

5. Since the PECI temperature is a relative value, the W83627UHG provides registers for each PECI Agent to
convert the relative value to a more traditional “absolute” format. The Tbase registers (Logical Device C,
CR[E1h]~CR[E4h]) store the “base” temperature. By means of BIOS/software, the desired base temperature can
be written to these registers. Important: the value must be positive. Otherwise abnormal temperature responses
will take place. Here is an example on how to obtain Tbase value:
(1). Use a digital thermometer on the surface of the PECI processor to measure the processor body temperature.
(2). Power up the system with the PECI processor. Run the processor to 100% loading.
(3). After the system is stable, read the PECI reading from Logical Device C, CR[E0h] ~ CR[E7h] of selected
Agents and record the value of the digital thermometer.
(4). Calculate Tbase. For example, if PECI = -10 and the digital thermometer is 50’C, then Tbase could be set to
60’C. (60 – 10 = 50).
7. The temperature values in Bank 1 and Bank 2 Index 50h & 51h are:
Bank 1, Index 50h & 51h = (Tbase) + (PECI Agent relative temperature)
Bank 2, Index 50h & 51h = (Tbase) + (PECI Agent relative temperature)
Agent 1 as the temperature source, the reported temperature will be 62°C (-10 + 72).
Index 50h & 51h or Bank 2 Index 50h & 51h reading does not reflect the actual temperature of the
processor.
6. There are two temperature reading registers in the W83627UHG: Bank1, Index 50h & 51h, and Bank2, Index
50h & 51h. The source of the Bank 1, Index 50h & 51h value is determined by the value programmed into the
CPUFANOUT monitor Temperature source select register (Hardware Monitor Device, Bank 0, Index 49h, bits
(2..0)). The source of Bank 2, Index 50h & 51h value is determined by the value programmed into the
SYSFANOUT monitor Temperature source select register (Hardware Monitor Device, Bank 0, Index 4Ah,
bits(7..5)).
Example:
If the PECI relative temperature of agent 1 is -10; Tbase is set to 72°C, and Bank0 Index 49h selects PECI
Please be noted that when the temperature source is selected as PECI temperature source, the Bank 1
3. In addition, each PECI Agent relative temperature can be read in Logical Device C, CR[E0h] ~ CR[E7h],
as long as Logical Device C, CR[E8h] bit 3 is set to “1”. When this bit is “1”, Logical Device C, CR[E0h] ~
CR[E7h] become “Read Only” registers.
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W83627UHG/NCT6627UD
Publication Release Date: October 26, 2010
Revision 1.7