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Explanation of pwm example code please

Hi, I need to configure pwm with 14uSec off time and 46uSec on time. I had a look at the pwm example in the install directory and also : developer.nordicsemi.com/.../a00039.html. But it is bit confusing, in the sense, if I need to set a duty cycle of 25% which registers to change. When I change the duty_cycle to 250, or, 100(in the local variable "duty_cycle"), there is no effect in the PWM wave generated. The On and Off times are 256msec always. Even tried pressing the configured buttons, but still no change in duty cycle. Attached my code here: main.c

Questions:

  1. Which register to change to set a desired duty cycle(say 25% off time and 75% on time)
  2. If I want to use the same PWM module for generating 25% duty cycle outputting on PIN1 for the first time, then 100% duty cycle outputting on PIN2 the next time and the above continues forever, do I need to deinit the gpiote and configure(nrf_gpio_tsk_config) every time I swap the PWM pins?
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  • Hi Ole, Thanks for your reply and sorry for not being clear. I needed to control the PWM pulse duty cycle via BLE. Initially the duty cycle would be 75% (42usec on time, 14usec off time), after getting an input from the BLE bonded phone connection, the duty cycle would reduce(example: 50%). After getting a second input from BLE bonded phone connection, the period of the PWM pulse would reduce (for example, period of PWM pulse would reduce from 56usec to 24usec with on time 10usec and off time 14usec), etc.

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  • Hi Ole, Thanks for your reply and sorry for not being clear. I needed to control the PWM pulse duty cycle via BLE. Initially the duty cycle would be 75% (42usec on time, 14usec off time), after getting an input from the BLE bonded phone connection, the duty cycle would reduce(example: 50%). After getting a second input from BLE bonded phone connection, the period of the PWM pulse would reduce (for example, period of PWM pulse would reduce from 56usec to 24usec with on time 10usec and off time 14usec), etc.

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