REV. 0

ADM1031

–23–

Table XII. Registers

Address A7–A0

Register Name

in Hex

Comments

Value Registers

0x08–0x1E

See Table XIII.

Device ID Register

0x3D

This location contains the device identification number. Since this

device is the ADM1031, this register contains 0x31. This register is

read only.

Company ID

0x3E

This location contains the company identification number (0x41).

This register is read only.

THERM Behavior/Revision

0x3F

This location contains the revision number of the device. The lower

four bits reflect device revisions [3:0]. Bit 7 of this register is the

THERM-to-fan enable bit. See Table XXII.

Configuration Register 1

0x00

See Table XIV. Power-on value = 1001 0000.

Configuration Register 2

0x01

See Table XV. Power-on value = 0111 1111.

Status Register 1

0x02

See Table XVI. Power-on value = 0000 0000.

Status Register 2

0x03

See Table XVII. Power-on value = 0000 0000.

Manufacturer’s Test Register

0x07

This register is used by the manufacturer for test purposes only. This

register should not be read from or written to in normal operation.

Fan Characteristics Register 1

0x20

See Table XIX. Power-on value = 0101 1101.

Fan Characteristics Register 2

0x21

See Table XX. Power-on value = 0101 1101.

Fan Speed Configuration Register

0x22

See Table XXI. Power-on value = 0101 0101.

Fan Filter Register

0x23

See Table XXII. Power-on value = 0101 0000.

0x24

See Table XXIII. Power-on value = 0100 0001.

0x25

See Table XXIV. Power-on value = 0110 0001.

0x26

See Table XXV. Power-on value = 0110 0001.

Table XIII. Value Registers

Address

Read/Write

Description

0x06

Read/Only

Extended Temperature Resolution (see Table XVIII).

0x08

Read/Write

Fan 1 Speed—this register contains the value of the Fan 1 tach measurement.

0x09

Read/Write

Fan 2 Speed—this register contains the value of the Fan 2 tach measurement.

0x0A

Read/Only

Local Temperature Value—this register contains the 8 MSBs of the local temperature measurement.

0x0B

Read/Only

Remote 1 Temperature Value—this register contains the 8 MSBs of the Remote 1 temperature reading.

0x0C

Read/Only

Remote 2 Temperature Value—this register contains the 8 MSBs of the Remote 2 temperature reading.

0x0D

Read/Write

Local Temperature Offset—See Table XXVII. (Power-On Default = 00h.)

0x0E

Read/Write

Remote 1 Temperature Offset—See Table XXVIII. (Power-On Default = 00h.)

0x0F

Read/Write

Remote 2 Temperature Offset—See Table XXIX. (Power-On Default = 00h.)

0x10

Read/Write

Fan 1 Tach High Limit—this register contains the limit for the Fan 1 tach measurement. Since the

tach circuit counts between pulses, a slow fan will result in a large measured value, so exceeding the

limit is the way to detect a slow or stalled fan. (Power-On Default = FFh.)

0x11

Read/Write

Fan 2 Tach High Limit—this register contains the limit for the Fan 2 tach measurement. Since the

tach circuit counts between pulses, a slow fan will result in a large measured value, so exceeding the

limit is the way to detect a slow or stalled fan. (Power-On Default = FFh.)

0x14

Read/Write

Local Temperature High Limit (Power-On Default 60

°C).

0x15

Read/Write

Local Temperature Low Limit (Power-On Default 0

°C).

0x16

Read/Write

Local Temperature Therm Limit (Power-On Default 70

°C).

0x18

Read/Write

Remote 1 Temperature High Limit (Power-On Default 80

°C).

0x19

Read/Write

Remote 1 Temperature Low Limit (Power-On Default 0

°C).

0x1A

Read/Write

Remote 1 Temperature Therm Limit (Power-On Default 100

°C).

0x1C

Read/Write

Remote 2 Temperature High Limit (Power-On Default 80

°C).

0x1D

Read/Write

Remote 2 Temperature Low Limit (Power-On Default 0

°C).

0x1E

Read/Write

Remote 2 Temperature Therm Limit (Power-On Default 100

°C).