emc2104 Standard Microsystems Corp., emc2104 Datasheet - Page 62

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

ADDR
ADDR
2Ah
2Bh
Revision 1.74 (05-08-08)
6.17
6.18
R/W
R/W
R/W
R/W
Bit 1 - SPIN_INT_EN1 - Allows the FAN_SPIN1 bit to assert the ALERT# pin.
Bit 0 - STALL_INT_EN1 - Allows the FAN_STALL1 bit or DRIVE_FAIL1 bit to assert the ALERT# pin.
The PWM Config Register controls the output type and polarity of all PWM outputs.
Bit 1 - POLARITY2 - Determines the polarity of PWM2 (if enabled).
Bit 0 - POLARITY1 - Determines the polarity of PWM1 (if enabled).
The PWM Base Frequency Register determines the base frequency that is used with the PWM Divide
register to determine the final PWM frequency. Each PWM driver uses the same divide ratio as set by
the PWM Divide Register.
Bits 3-2 - PWM_BASE2[1:0] - Determines the base frequency of the PWM2 driver (PWM2 / GPIO4
pin).
Bits 1-0 - PWM_BASE1[1:0] - Determines the base frequency of the PWM1 driver (PWM1).
PWM Configuration Register
PWM Base Frequency Register
REGISTER
REGISTER
PWM Base
Frequency
‘1’ - the FAN_STALL 2 or DRIVE_FAIL2 bits will assert the ALERT# pin if set.
‘0’ (default) - the FAN_SPIN1 bit will not assert the ALERT# pin though it will still update the Status
Register normally.
‘1’ - the FAN_SPIN1 bit will assert the ALERT# pin.
‘0’ (default) - the FAN_STALL1 bit or DRIVE_FAIL1 bit will not assert the ALERT# pin though will
still update the Status Register normally.
‘1’ - the FAN_STALL1 or DRIVE_FAIL1 bit will assert the ALERT# pin if set.
Config
PWM
B7
B7
-
-
Table 6.23 PWM Base Frequency Register
Table 6.22 PWM Configuration Register
B6
B6
-
-
DATASHEET
Dual RPM-Based PWM Fan Controller with Hardware Thermal Shutdown
B5
B5
-
-
62
B4
B4
-
-
PWM_
BASE
2_1
B3
B3
-
PWM_
BASE
2_0
B2
B2
-
PWM_
RITY2
POLA
BASE
1_1
B1
B1
PWM_
RITY1
SMSC EMC2104
POLA
BASE
1_0
B0
B0
Datasheet
DEFAULT
DEFAULT
00h
FFh