Translations:Buzzer/10/en

To work with pwm through sysfs you need:

1. Export port

   echo 0 > /sys/class/pwm/pwmchip0/export
   

   After that, the /sys/class/pwm/pwmchip0/pwm0 directory appears
2. Write the pwm period in nanoseconds

   echo 250000 > /sys/class/pwm/pwmchip0/pwm0/period # set the period to 250,000 ns, i.e. in 250µs, which corresponds to a frequency of 4kHz
   

3. Record volume (calculated from duty-cycle)

   echo 125000 > /sys/class/pwm/pwmchip0/pwm0/duty_cycle # maximum volume is reached when duty_cycle = period / 2 => set duty_cycle to 125,000 ns
   

4. Enable PWM output

   echo 1 > /sys/class/pwm/pwmchip0/pwm0/enable