Very simple Rp2040 PWM duty control class

Rp2040PWM.hpp

#include "hardware/pwm.h"

class PiPWM {
public:
  explicit PiPWM(uint pin);
  void start();
  void stop();

  ~PiPWM();
  
  // duty 0-100
  void setDuty(uint8_t duty);

private:
  uint _pin;
  uint _slice_num;
  uint _channel;
  const uint _maxWrap = 500;
};

PiPWM::PiPWM(uint pin): _pin(pin) {
  gpio_set_function(pin, GPIO_FUNC_PWM);
  _slice_num = pwm_gpio_to_slice_num(pin);
  _channel = pwm_gpio_to_channel(pin);
}

void PiPWM::start() {
  pwm_set_wrap(_slice_num, 1);
  pwm_set_chan_level(_slice_num, _channel, 1);

  pwm_set_enabled(_slice_num, true);

  pwm_set_wrap(_slice_num, _maxWrap);
};

void PiPWM::stop() {
  pwm_set_enabled(_slice_num, false);
};

PiPWM::~PiPWM() {
  stop();
};

// duty 0-100
void PiPWM::setDuty(uint8_t duty) {
  if (duty >= 0 && duty <= 100) {
    uint16_t x = (_maxWrap/100) * duty;
      pwm_set_chan_level(_slice_num, _channel, x);
  }
}