emc2104 Standard Microsystems Corp., emc2104 Datasheet - Page 60

• Manufacturer Part Number: emc2104
• Description: Emc2104 Dual Rpm-based Pwm Fan Controller With Hardware Thermal Shutdown
• Manufacturer: Standard Microsystems Corp.

ADDR
ADDR
27h
28
Revision 1.74 (05-08-08)
R/W
R/W
6.14
6.15
R/W
R-C
REGISTER
Interrupt
REGISTER
Enable
Fan Status
Register
The Fan Status Register contains the status bits associated with each fan driver. This register is
cleared when read if the error condition has been removed.
Bit 7 - WATCH - This bit is asserted ‘1’ if the host has not programmed the fan driver(s) within four (4)
seconds after power up.
Bit 6 - DRIVE_FAIL2 - Indicates that the RPM based Fan Speed Control Algorithm cannot drive Fan
2 to the desired target setting at maximum drive. This bit can be masked from asserting the ALERT#
pin.
Bit 6 - DRIVE_FAIL1 - Indicates that the RPM based Fan Speed Control Algorithm cannot drive Fan
1 to the desired target setting at maximum drive. This bit can be masked from asserting the ALERT#
pin.
Bit 3 - FAN_SPIN 2- This bit is asserted ‘1’ if the Spin up Routine for Fan 2 cannot detect a valid
tachometer reading within its maximum time window. This bit can be masked from asserting the
ALERT# pin.
Bit 2 - FAN_STALL 2 - This bit is asserted ‘1’ if the tachometer measurement on Fan 2 detects a stalled
fan. This bit can be masked from asserting the ALERT# pin.
Bit 1- FAN_SPIN1- This bit is asserted ‘1’ if the Spin up Routine for Fan 1 cannot detect a valid
tachometer reading within its maximum time window. This bit can be masked from asserting the
ALERT# pin.
Bit 0 - FAN_STALL1 - This bit is asserted ‘1’ if the tachometer measurement on Fan 1 detects a stalled
fan. This bit can be masked from asserting the ALERT# pin.
The Interrupt Enable Register controls the masking for each temperature channel. When a channel is
masked, it will not cause the ALERT# pin to be asserted when an error condition is detected.
Bit 5 - VOLT4_INT_EN - Allows the Voltage Input 4 channel to assert the ALERT# pin.
Fan Status Register
Interrupt Enable Register
‘0’ - The RPM based Fan Speed Control Algorithm can drive Fan 2 to the desired target setting.
‘1’ - The RPM based Fan Speed Control Algorithm cannot drive Fan 2 to the desired target setting
at maximum drive.
‘0’ - The RPM based Fan Speed Control Algorithm can drive Fan 1 to the desired target setting.
‘1’ - The RPM based Fan Speed Control Algorithm cannot drive Fan 1 to the desired target setting
at maximum drive.
WATCH
B7
-
B7
_FAIL2
B6
DRIVE
Table 6.20 Interrupt Enable Register
-
B6
Table 6.19 Fan Status Register
VOLT4_I
NT_EN
DATASHEET
_FAIL1
DRIVE
B5
B5
Dual RPM-Based PWM Fan Controller with Hardware Thermal Shutdown
60
EXT4_I
NT_EN
B4
B4
-
EXT3_I
SPIN2
NT_EN
FAN_
B3
B3
STALL2
EXT2_I
NT_EN
FAN_
B2
B2
EXT1_I
NT_EN
SPIN1
FAN_
B1
B1
SMSC EMC2104
STALL1
INT_IN
T_EN
FAN_
Datasheet
B0
B0
DEFAULT
DEFAULT
00h
00h