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Register 48h, 49h, 4Ah – Temp x

* Cooling Action (Power-On Default 00h)

Bit

Name

R/W

Description

0

Fan 1 = 0

R/W

If a Temp x

* out-of-limit event is generated such that fans should be driven at

Alarm Speed, Fan 1 will be set to this speed when this bit is set. If no Temp x

*

out-of-limit event is present, Fan 1 will be set to the speed determined by the

automatic fan speed control circuit as a result of temperature measurements on

the Temp x

* channel when this bit is set. If this bit is not set, Temp x* tem-

perature measurements will have no effect on the speed of Fan 1.

1

Fan 2 = 0

R/W

If a Temp x

* out-of-limit event is generated such that fans should be driven

at Alarm Speed, Fan 2 will be set to this speed when this bit is set. If no Temp

x

* out-of-limit event is present, Fan 2 will be set to the speed determined by

the automatic fan speed control circuit as a result of temperature measure-

ments on the Temp x

* channel when this bit is set. If this bit is not set,

Temp x temperature measurements have no effect on the speed of Fan 2.

While in theory it is possible, through setting of Bits 0 and 1 in registers 48h

to 4Ah, to have any temperature channel controlling any fan, in practice this

is not feasible. A subset of possibilities only are supported as follows:

Case 1:

TDM1 controlling Fan 1

(Bit 0 in 49h set and/or

TDM2 controlling Fan 2

Bit 1 in 4Ah set, only)

Case 2:

Local controlling Fan 1 and/or Fan 2

(Bits 0, 1 in 48h only set)

Case 3:

TDM1 controlling Fan 1 and/or Fan 2 (Bits 0, 1 in 49h only set)

Case 4:

TDM2 controlling Fan 1 and/or Fan 2 (Bits 0, 1 in 4Ah only set)

Case 5:

Fan 1 and/or Fan 2 set to max speed

(Bits 0, 1 in 48h, 49h,

(Default)

determined by temperature

4Ah all set)

measurements on all three channels.

Other:

If Bits 0,1 in registers 48h, 49h, 4Ah are

set inconsistent with these cases, fans

will run at the speeds determined by

the normal speed registers.

2

Reserved

R

Unused. Will read back 0.

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.

*“x” denotes the number of the temperature channel. Register 48h is for the Local temperature channel. 49h is for Remote 1 Temp (D1), 4Ah is for Remote 2

Temp (D2).

ADM1029