ADM1031

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25

Table 15. Register 0y01 Configuration 2 Power−On Default = 7FH

Bit

Name

R/W

Description

0

PWM 1 En

R/W

Enables Fan 1 PWM output when this bit is a “1.”

1

PWM 2 En

R/W

Enables Fan 2 PWM output when this bit is a “1.”

2

TACH 1 En

R/W

Enables Tach 1 input when set to “1.”

3

TACH 2 En

R/W

Enables Tach 2 input when set to “1.”

4

Loc Temp En

R/W

Enables Interrupts on local temperature channel when set to “1.”

5

Remote 1 Temp En

R/W

Interrupts on Remote 1 Channel when set to “1.” Default is normally enabled, except

when a diode fault is detected on powerup.

6

Remote 2 Temp En

R/W

Enables Interrupts on Remote 2 Channel when set to “1.” Default is normally enabled,

except when a diode fault is detected on powerup.

7

SW Reset

R/W

When set to “1,” resets the device. Self−clears. Powerup Default = 0.

Table 16. Register 0y02 Status Register 1 Power−On Default = 00H

Bit

Name

R/W

Description

0

Alarm 1 Speed

R

This bit is set to “1” when fan is running at alarm speed. Once read, this bit is not

reasserted on next monitoring cycle, even if the fan is still running at alarm speed.

1

Fan 1 Fault

R

This bit is set to “1” if Fan 1 becomes stuck or is running under speed.

2

Remote 1 High

R

“1” indicates Remote 1 high temperature limit has been exceeded. If the temperature

is still outside the Remote 1 Temp High Limit, this bit reasserts on next monitoring

cycle.

3

Remote 1 Low

R

“1” indicates Remote 1 low temperature limit exceeded (below). If the temperature is

still outside the Remote 1 Temp Low Limit, this bit reasserts on next monitoring cycle.

4

Remote 1 THERM

R

“1” indicates Remote 1 temperature THERM limit has been exceeded. This bit is

cleared on a read of Status Register 1.

5

Remote Diode 1 Error

R

This bit is set to “1” if a short or open is detected on the Remote 1 temperature

channel. This test is only done on powerup, and if set to 1 cannot be cleared by

reading the Status Register 1.

6

Local Temp High

R

This bit is set to “1” if a short or open is detected on the Remote 1 temperature

channel. This test is only done on powerup, and if set to 1 cannot be cleared by

reading the Status Register 1.

7

Local Temp Low

R

“1” indicates Local Temp Low Limit has been exceeded (below). If the temperature is

still outside the Local Temp Low Limit, this bit reasserts on next monitoring cycle.

Table 17. Register 0y03 Status Register 2 Powerup Default = 00H

Bit

Name

R/W

Description

0

Alarm 2 Speed

R

This bit is set to “1” when Fan 2 is running at alarm speed. Once read, this bit is not

reasserted on next monitoring cycle, even if the fan is still running at alarm speed.

1

Fan 2 Fault

R

This bit is set to “1” if Fan 2 becomes stuck or is running under speed.

2

Remote 2 High

R

“1” indicates Remote 2 high temperature limit has been exceeded. If the temperature

is still outside the Remote 2 Temp High Limit, this bit reasserts on the next monitoring

cycle.

3

Remote 2 Low

R

“1” indicates Remote 2 low temperature limit exceeded (below). If the temperature is

still outside the Remote 2 Temp Low Limit, this bit reasserts on the next monitoring

cycle.

4

Remote 2 THERM

R

“1” indicates Remote 2 temperature THERM limit has been exceeded. This bit is

cleared on reading Status Register 2.

5

Remote Diode 2 Error

R

This bit is set to “1” if a short or open is detected on the Remote 2 temperature

channel. This test is only done on powerup, and if set to 1 cannot be cleared by

reading Status Register 2.

6

Local THERM

R

“1” indicates local temperature THERM limit has been exceeded. This bit clears on a

read of Status Register 2.

7

THERM

R

Set to “1” when THERM is pulled low as an input. This bit clears on a read of Status

Register 2.