NAME

SYNOPSIS

DESCRIPTION

temperature_sensor should be the name of the sysctl variable used to read the system temperature. pwm_device should be the name of the PWM device that controls the system fan. If an unqualified name is provided, /dev/pwm is automatically prepended.

When called with the -s option, fand will print the current status of the temperature sensor and the PWM state and exit. This can be useful when determining the required temperature multiplier and other options.

The options are as follows:

-d duty

The duty cycle (in nanoseconds or percentage) of the PWM channel for the default (low) temperature threshold. Duty is the portion of the period during which the signal is asserted.

-D duty

The duty cycle (in nanoseconds or percentage) of the PWM channel for the high temperature threshold. Duty is the portion of the period during which the signal is asserted.

-f

Run fand in the foreground. Also enables more verbose output.

-i seconds

The temperature polling interval, in seconds (Default: 60)

-I

Invert PWM signal polarity

-K

Converts the temperature sensor reading from degrees Kelvin

-m multiplier

Multiplier applied to reading from temperature sensor (Default: 1.0)

-o temperature

Temperature to deactivate fan, in °C (Default: 50)

-p period

The period in nanoseconds of the PWM channel for the default (low) temperature threshold (Default: 0)

-P period

The period in nanoseconds of the PWM channel for the high temperature threshold (Default: 0)

-r path

The PID file path (Default: /var/run/fand.pid)

-s

Show current temperature and PWM status, then exit.

-t temperature

Default (low) temperature to enable the fan, in °C (Default: 50)

-T temperature

High temperature threshold, in °C (Default: not set)

-v

Print program version and exit

EXAMPLES

• Using the "hw.temp.CPU" sensor and the pwmc1.0 controller, run the fan at half duty cycle when the temperature reaches 45C and run at full when the temperature rises above 60C. Disable the fan if the temperature falls below 35C. When reading from the sensor, assume value is in tenth degrees Kelvin.

  fand -t 45 -p 50000 -d "50%" -T 60 -o 35 -K -m 0.1 hw.temp.CPU pwmc1.0
      

SEE ALSO

AUTHORS