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30 .Nd configure PWM (Pulse Width Modulation) hardware
44 utility can be used to configure pwm hardware.
48 device to communicate with the hardware.
49 Some PWM hardware supports multiple output channels within a single
50 controller block; each
52 instance controls a single PWM channel.
56 .Pa /dev/pwm/pwmcX.Y ,
59 is the controller unit number and
61 is the channel number within that unit.
63 The options are as follows:
64 .Bl -tag -width "-f device"
70 If an unqualified name is provided,
72 is automatically prepended.
74 Show the configuration of the PWM channel.
76 Disable the PWM channel.
78 Configure the duty cycle (in nanoseconds or percentage) of the PWM channel.
79 Duty is the portion of the
81 during which the signal is asserted.
83 Enable the PWM channel.
85 Configure the period (in nanoseconds) of the PWM channel.
87 Invert PWM signal polarity
92 Show the configuration of the PWM channel:
94 pwm -f /dev/pwm/pwmc0.1 -C
97 Configure a 50000 ns period and a 25000 ns duty cycle
98 and enable the channel:
100 pwm -f pwmc1.1 -E -p 50000 -d 25000
103 Configure a 50% duty cycle on the device and channel which
109 pwm -f backlight -d 50%
124 utility and this manual page were written by
125 .An Emmanuel Vadot Aq Mt manu@FreeBSD.org .