pwm command
Synopsis
pwm invert <pwm_dev_num> <channel> <polarity>
pwm config <pwm_dev_num> <channel> <period_ns> <duty_ns>
pwm enable <pwm_dev_num> <channel>
pwm disable <pwm_dev_num> <channel>
Description
The pwm
command is used to access and configure PWM (Pulse Width Modulation)
signals.
pwm invert
If the value of
polarity
is 0, the default polarity is used.If the value of
polarity
is 1, the polarity is inverted.
pwm config
Configure the period and duty period in nanoseconds.
pwm enable
Enable output on the configured device and channel.
pwm disable
Disable output on the configured device and channel.
- pwm_dev_num
Device number of the pulse width modulation device
- channel
Output channel of the PWM device
- polarity
0 - Use normal polarity
1 - Use inverted polarity
- duty_ns
Duty period in ns
- period_ns
Period time in ns
Examples
Configure device 0, channel 0 to 20 µs period and 14 µs (that is, 70%) duty period:
=> pwm config 0 0 20000 14000
Enable output on the configured device and channel:
=> pwm enable 0 0
Disable output on the configured device and channel:
=> pwm disable 0 0
Invert the signal on the configured device and channel:
=> pwm invert 0 0 1
Configuration
The pwm
command is only available if CONFIG_CMD_PWM=y.
Return value
If the command succeeds, the return value $?
is set to 0. If an error occurs, the
return value $?
is set to 1.