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ADM1029

TEMPERATURE REGISTERS

Register 06h – Temp Devices Installed (Power-On Default 0000 0??1)

Bit

Name

R/W

Description

0

Local Temp = 1

R

This bit is permanently set to 1 since the local temperature sensor is always

available.

1

Remote 1 Temp = ?

R

This bit is set to 1 if the Remote 1 temperature sensor (TDM1) is installed.

(Automatically detected on power-up.)

2

Remote 2 Temp = ?

R

This bit is set to 1 if the Remote 2 temperature sensor (TDM2) is installed.

(Automatically detected on power-up.)

3

Reserved

R

Unused. Will read back 0.

4

Reserved

R

Unused. Will read back 0.

5

Reserved

R

Unused. Will read back 0.

6

Reserved

R

Unused. Will read back 0.

7

Reserved

R

Unused. Will read back 0.

NOTE

Question marks on this and following pages indicate bit settings that depend on the state of certain pins on power-up.

Register 30h, 31h, 32h – Temp x

* Offset Registers (Power-On Default 00h)

Bit

Name

R/W

Description

<7:0>

Offset

R/W

This register contains an offset value that is automatically added to the tem-

perature value to reduce the effects of systemic offset errors.

*“x” denotes the number of the temperature channel. Register 30h is for Local temperature channel, 31h is for Remote 1 Temp (D1), 32h is for Remote 2 Temp (D2).

Register 40h, 41h, 42h – Temp x

* Fault Action (Power-On Default 08h)

Bit

Name

R/W

Description

0

Assert CFAULT on

R/W

When this bit is set, CFAULT will be asserted when the Temp x* tempera-

OT = 0

ture exceeds the Temp x* Temperature High Limit, not otherwise.

1

Alarm speed on OT = 0

R/W

When this bit is set, the fans(s) will go to alarm speed when the Temp x*

temperature exceeds the Temp x* Temperature High limit, not otherwise.

2

INT on OT = 0

R/W

When this bit is set, INT will be asserted when the Temp x* temperature

exceeds the Temp x* Temperature High Limit, not otherwise.

3

Alarm below low = 0

R/W

This bit indicates whether an alarm (INT, CFAULT, or Alarm Speed) is

asserted when temperature goes above or below the Low Limit. 1 = above,

0 = below. This bit is set to 1 at power-up if automatic fan speed control is

enabled by Pin 18, cleared otherwise.

4

Assert CFAULT on

R/W

When this bit is set, CFAULT will be asserted when the Temp x* temperature

UT = 0

crosses the Temp x* Temperature Low Limit, not otherwise. Bit 3 decides

whether CFAULT is asserted for going above or below the Low Limit. This bit is

set to 1 if Automatic Fan Speed Control is enabled on power-up.

5

Alarm speed on UT = 0

R/W

When this bit is set, the fans(s) will go to alarm speed when the Temp x*

temperature crosses the Temp x* Temperature Low Limit, not otherwise. Bit

3 decides whether Alarm Speed is asserted for going above or below the Low Limit.

6

INT on UT = 0

R/W

When this bit is set, INT will be asserted when the Temp x* temperature

crosses the Temp x* Temperature Low Limit, not otherwise. Bit 3 decides

whether INT is asserted for going above or below the Low Limit.

7

Latch Temp Fault = 0

R/W

This bit latches a temperature out-of-limit event (i.e., when the temperature

goes above the high limit or crosses the low limit) on the Temp x* channel.

This bit is cleared by writing a 0 to it.

*“x” denotes the number of the temperature channel. Register 40h is for the Local temperature channel, 41h is for Remote 1 Temp (D1), 42h is for Remote 2

Temp (D2).