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30 .Nd configure PWM (Pulse Width Modulation) hardware
43 utility can be used to configure pwm hardware.
47 device to communicate with the hardware.
48 Some PWM hardware supports multiple output channels within a single
49 controller block; each
51 instance controls a single PWM channel.
55 .Pa /dev/pwm/pwmcX.Y ,
58 is the controller unit number and
60 is the channel number within that unit.
62 The options are as follows:
63 .Bl -tag -width "-f device"
69 If an unqualified name is provided,
71 is automatically prepended.
73 Show the configuration of the PWM channel.
75 Disable the PWM channel.
77 Configure the duty cycle (in nanoseconds or percentage) of the PWM channel.
78 Duty is the portion of the
80 during which the signal is asserted.
82 Enable the PWM channel.
84 Configure the period (in nanoseconds) of the PWM channel.
89 Show the configuration of the PWM channel:
91 pwm -f /dev/pwm/pwmc0.1 -C
94 Configure a 50000 ns period and a 25000 ns duty cycle
95 and enable the channel:
97 pwm -f pwmc1.1 -E -p 50000 -d 25000
100 Configure a 50% duty cycle on the device and channel which
106 pwm -f backlight -d 50%
121 utility and this manual page were written by
122 .An Emmanuel Vadot Aq Mt manu@FreeBSD.org .