EMC2103 Standard Microsystems Corporation, EMC2103 Datasheet - Page 51

• Manufacturer Part Number: EMC2103
• Description: Rpm-based Fan Controller with HW Thermal Shutdown
• Manufacturer: Standard Microsystems Corporation

RPM-Based Fan Controller with HW Thermal Shutdown
Datasheet
SMSC EMC2103
ADDR
ADDR
6.14
6.15
27h
28
R/W
R/W
R/W
R-C
The Fan Status Register contains the status bits associated with each fan driver.
Bit 7 - WATCH - This bit is asserted ‘1’ if the host has not programmed the fan driver within four (4)
seconds after power up (i.e. the Watchdog Timer has timed out. See
Bit 5 - DRIVE_FAIL - Indicates that the RPM based Fan Speed Control Algorithm cannot drive the Fan
to the desired target setting at maximum drive. This bit can be masked from asserting the ALERT pin.
Bit 1- FAN_SPIN - This bit is asserted ‘1’ if the Spin up Routine for the Fan cannot detect a valid
tachometer reading within its maximum time window. This bit can be masked from asserting the ALERT
pin.
Bit 0 - FAN_STALL - This bit is asserted ‘1’ if the tachometer measurement on the Fan 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 3 - EXT3_INT_EN (EMC2103-2 only) - Allows the External Diode 3 to assert the ALERT pin.
Bit 2 - EXT2_INT_EN (EMC2103-2 only) - Allows the External Diode 2 to assert the ALERT pin.
Bit 1 - EXT1_INT_EN - Allows the External Diode 1 to assert the ALERT pin.
Fan Status Register
Interrupt Enable Register
‘0’ - The RPM based Fan Speed Control Algorithm can drive Fan to the desired target setting.
‘1’ - The RPM based Fan Speed Control Algorithm cannot drive Fan to the desired target setting
at maximum drive.
‘0’ (default) - The ALERT pin will not be asserted for any error condition associated with External
Diode 3 channel.
‘1’ - The ALERT pin will be asserted for an error condition associated with External Diode 3
channel.
‘0’ (default) - The ALERT pin will not be asserted for any error condition associated with External
Diode 2 channel.
‘1’ - The ALERT pin will be asserted for an error condition associated with External Diode 2
channel.
‘0’ (default) - The ALERT pin will not be asserted for any error condition associated with External
Diode 1 channel.
REGISTER
REGISTER
Fan Status
Interrupt
Enable
Register
B7
-
WATCH
B7
Table 6.21 Interrupt Enable Register
B6
-
Table 6.20 Fan Status Register
B6
-
B5
-
DATASHEET
DRIVE
_FAIL
B4
B5
-
51
EXT3_I
NT_EN
B4
B3
-
B3
-
EXT2_I
NT_EN
B2
B2
-
FAN_
EXT1_I
NT_EN
SPIN
Section
B1
B1
5.9.
STALL
Revision 0.85 (01-29-08)
INT_IN
FAN_
T_EN
B0
B0
DEFAULT
DEFAULT
00h
00h