ADM1029
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24
Figure 36. Fan Configuration Flowchart
SET FAN 1 = 33%
SET FAN 2 = 33%
CONFIGURE FAN
NORMAL SPEED
FAN 1 (REG 0X60)
FAN 2 (REG 0X61)
BIT 0 = 1
ASSERT CFAULT
ON FAN FAULT (TACH FAILURE OR FAULT ASSERTION)
BIT 1 = 1
ASSERT INT
ON FAN FAULT (TACH FAILURE OR FAULT ASSERTION)
BIT 2 = 1
ASSERT CFAULT
IF FAN HOT UNPLUGGED
BIT 3 = 1
ASSERT INT
IF FAN HOT UNPLUGGED
BIT 4 = 1
THERMAL OVERRIDE IF IN SLEEP MODE (FAN RUNS AT ALARM SPEED)
BIT 5 = 1
DRIVE FAULT LOW IF A FAN FAULT IS DETECTED
BIT 6 = 1
IF CFAULT
PULLED LOW EXTERNALLY, RUN FAN AT HOT-PLUG SPEED
BIT 7 = 1
IF CFAULT
PULLED LOW ESTERNALLY, RUN FAN AT ALLARM SPEED
CONFIGURE FAN
ALARM SPEED
FAN 1 (REG 0X60)
FAN 2 (REG 0X61)
CONFIGURE FAN
HOT-PLUG SPEED
FAN 1 (REG 0X68)
FAN 2 (REG 0X69)
CONFIGURE FAN FAULT
ACTION
FAN 1 (REG 0X18)
FAN 2 (REG 0X19)
CONFIGURE FAN FAULT
MASK REGISTERS
FAN 1 (REG 0X20)
FAN 2 (REG 0X21)
DEFAULT
FAN 1 = 100%
FAN 2 = 100%
DEFAULT
FAN 1 = 100%
FAN 2 = 100%
FAN FAULT MASK (CONFIGURE REG 0X20 FOR
FAN 1, REG 0X21 FOR FAN 2)
BIT 0 = 1
RUN FAN 1 AT ALARM SPEED
IF FAN FAULT IS DETECTED
BIT 1 = 1
RUN FAN 2 AT ALARM SPEED
IF FAN FAULT IS DETECTED
BIT 2 7
DONT CARE
7
6
5
4
3
2
1
0
FAN TACH
FAILURE OR
FAULT PIN
LOW?
FAN RUNS AT ALARM SPEED
YES
CFAULT
YES
YES
YES
YES
YES
YES
YES
YES
INT
INT
CFAULT
FAN RUNS AT HOT-PLUG SPEED
FAN RUNS AT ALARM SPEED
FAN 1 RUNS ALARM SPEED
FAN 2 RUNS ALARM SPEED
YES
FAN TACH
FAILURE OR
FAULT PIN
LOW?
HAS A FAN
BEEN HOT
UNPLUGGED?
HAS A FAN
BEEN HOT
UNPLUGGED?
OVER-
TEMPERATURE
DETECTED IN
SLEEP MODE?
FAN TACH
FAILURE OR
FAULT PIN
LOW?
HAS CFAULT
BEEN PULLED
LOW?
HAS CFAULT
BEEN PULLED
LOW?
FAN TACH
FAILURE OR
FAULT PIN
LOW?
FAN TACH
FAILURE OR
FAULT PIN
LOW?
FAN FAULT ACTION (CONFIGURE REG 0X18 FOR FAN 1, REG 0X19 FOR FAN 2)