How to control the number of pulses using app_pwm library?

[nordicdev]

Hi, I would like to generate PWM waves with on/off period as low as 10usec.

1. How to stop the PWM and restart it? I tried this but does not stop the PWM:

   void pwm_start( void ) { nrf_drv_gpiote_out_task_enable(GPIO_YELLOW_LED_PIN_WII); app_pwm_enable(&PWM1); } void pwm_stop( void ) { app_pwm_disable(&PWM1); nrf_drv_gpiote_out_task_disable(GPIO_YELLOW_LED_PIN_WII); uint32_t err_code = app_pwm_uninit(&PWM1); APP_ERROR_CHECK(err_code);
   nrf_gpio_cfg_output(GPIO_YELLOW_LED_PIN_WII); nrf_gpio_pin_set(GPIO_YELLOW_LED_PIN_WII); }

2. How to control the number of PWM pulses? I want to output 1 PWM pulse upon button press. Thanks.

[Mahesh Venkitachalam]

I want to output 1-60 (depends upon the input from the BLE app) PWM pulses of on time 42usec and off time 14usec and then send 1 PWM pulse of on time 260usec and off time=0usec. Then wait for 10msec.

Is it necessary to use PWM for the above? Why not set/unset the GPIO pin directly? Won't that give you more control?

[Ole Bauck]

For this task it is best to use gpio or fickle with gpiote, ppi and timer and use another timer in counter mode to count the number of periods (1-60). Also take a look at ppi groups and enable/disable tasks. Depending on how many resources that are available you may be able to do this all automatically with only the CPU updating the number of periods (1-60).