PC87366 datasheet(197/240 Pages) NSC

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12.0 Temperature Sensor (TMS) (Continued)

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Figure 43. OTS and ALERT Temperature Response Diagrams

12.2.3

ALERT Response Read Sequence

The Read Channel Temperature register (RDCHT) holds the temperature value most recently read from the channel. The

Temperature Event Status register (TEVSTS) indicates any ALERT detected as long as VSB is maintained. ALERTs are

cleared by software.

When an IRQ or SMI is received, check the TEVSTS register to see which of the sensors detected an out-of-limit readout,

access the channel readouts, read the current value and status information, and clear any pending status bits.

12.2.4

Power-On Reset Default States

TMS always powers up in a known state. TMS power-up default conditions are:

1. Local temperature set to 0

°C.

2. Remote temperature set to 0

°C until the TMS senses a diode present on D+ and D- input pins.

3. Status register set to 00h.

4. Command register set to 00h; ALERT and OTS enabled, Standby mode deactivated.

OTS

Indicates when temperature is sampled by the A/D Converter.

TOS1

TOS2

THIGH

TLOW

ALERT

Indicates when temperature is sampled by the A/D Converter.

a: ALERT Signal

b: OTS Signal

TOS2

TLOW2

OTS

Indicates when temperature is sampled by the A/D Converter.

THIGH2

TLOW1

THIGH1

TOS1

ALERT

c: Combined ALERT and OTS Signals

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