Dual RPM-Based PWM Fan Controller with Hardware Thermal Shutdown
Datasheet
6.36
GPIO Direction Register
Table 6.53 GPIO Direction Register
B6 B5 B4 B3
ADDR
E1h
R/W
REGISTER
B7
B2
B1
B0
DEFAULT
GPIO
Direction 1
GPIO
GPIO
GPIO
R/W
-
-
-
-
-
00h
3_DIR 2_DIR 1_DIR
The GPIO Direction Register 1 controls the direction of GPIOs 1 through 6. When muxable pins are
not configured as a GPIO ports the respective bits are ignored.
Bit 5 - 0 - GPIOx_DIR - Controls the input / output state of GPIOs. The bit is not used if the pin is not
configured as a GPIO.
‘0’ (default) - The GPIO is configured as an input.
‘1’ - The GPIO is configured as an output.
6.37
GPIO / PWM Pin Output Configuration Register
Table 6.54 GPIO / PWM Pin Output Configuration Register
ADDR
R/W
REGISTER
B7
B6
B5
B4
B3
B2
B1
B0
DEFAULT
GPIO
Output
Config
PWM
1_OT
GPIO
3_OT
GPIO
2_OT
GPIO
1_OT
E2
R/W
-
-
-
-
00h
The GPIO Output Configuration Register controls the output pin type of each GPIO pin. These settings
apply to the pin if it is configured as a GPIO output or a PWM. Bit 6 - PWM1_OT - Determines the
output type for the PWM1 pin.
‘0’ (default) - The PWM1 output is configured as an open drain output (if enabled as a PWM
output).
‘1’ - The PWM1 output is configured as a push-pull output (if enabled as an a PWM output).
Bit 2 - 0 - GPIOx_OT - Determines the output type for GPIOx.
‘0’ (default) - GPIOx is configured as an open drain output (if enabled as an output).
‘1’ - GPIOxis configured as a push-pull output (if enabled as an output).
6.38
GPIO Input Register
Table 6.55 GPIO Input Register
ADDR
R/W
REGISTER
B7
B6
B5
B4
B3
B2
B1
B0
DEFAULT
GPIO
3_IN
GPIO
2_IN
GPIO
1_IN
E3h
R
GPIO Input
-
-
-
-
-
00h
The GPIO Input Register indicates the state of the corresponding GPIO pin regardless of the
functionality of the pin (GPIO, PWM, or TACH) or the direction of the GPIO (input, push-pull output,
open-drain output). When a GPIO is configured as an input, any change of state will assert the
ALERT# pin (unless GPIO interrupts are masked, see Section 6.15).
Revision 1.74 (05-08-08)
SMSC EMC2104
DATA8S0HEET
SMSC [ SMSC CORPORATION ]
