NUCLEO-C092RC开发板pwm+timer+控制呼吸

/* USER CODE BEGIN 2 */

  // Start the PWM channels for both LEDs

  // Note: Use the correct Timer handle and Channel defined by your configuration

  if (HAL_TIM_PWM_Start(&htim1, TIM_CHANNEL_2) != HAL_OK) // For LED on PC9

  {

    Error_Handler();

  }

  if (HAL_TIM_PWM_Start(&htim2, TIM_CHANNEL_1) != HAL_OK) // For LED on PA5

  {

    Error_Handler();

  }





  // --- Variables for breathing effect ---

  // Set PWM_MAX_VALUE to your timer's ARR (Auto-Reload Register) value

  // Assuming ARR was set to 999 for both timers in CubeMX for a 0-1000 range

  uint32_t pwm_max_value = 999;

  uint32_t brightness = 0;

  int8_t step = 5; // How much to change brightness each step

  uint8_t delay_ms = 10; // Delay between steps, controls breathing speed





  /* USER CODE END 2 */



  /* Infinite loop */

  /* USER CODE BEGIN WHILE */

  while (1)

  {

    /* USER CODE END WHILE */

          // --- Fade In ---

              for (brightness = 0; brightness <= pwm_max_value; brightness += step)

              {

                // Clamp brightness to max value in case step overshoots

                if (brightness > pwm_max_value) {

                    brightness = pwm_max_value;

                }



                // Set the PWM duty cycle (Compare value) for both LEDs simultaneously

                __HAL_TIM_SET_COMPARE(&htim1, TIM_CHANNEL_2, brightness); // LED on PC9

                __HAL_TIM_SET_COMPARE(&htim2, TIM_CHANNEL_1, brightness); // LED on PA5



                HAL_Delay(delay_ms); // Adjust delay for breathing speed

              }



               // Ensure brightness is exactly max value after loop

              __HAL_TIM_SET_COMPARE(&htim1, TIM_CHANNEL_2, pwm_max_value);

              __HAL_TIM_SET_COMPARE(&htim2, TIM_CHANNEL_1, pwm_max_value);

              HAL_Delay(delay_ms * 10); // Optional: Pause briefly at full brightness





              // --- Fade Out ---

              // Start slightly below max to avoid issues with unsigned wrap-around if step doesn't divide evenly

              for (brightness = pwm_max_value; brightness > 0; )

              {

                 // Decrement first, then check bounds

                 if (brightness <= step) { // Prevent underflow for unsigned int

                      brightness = 0;

                 } else {

                     brightness -= step;

                 }



                // Set the PWM duty cycle (Compare value) for both LEDs simultaneously

                __HAL_TIM_SET_COMPARE(&htim1, TIM_CHANNEL_2, brightness); // LED on PC9

                __HAL_TIM_SET_COMPARE(&htim2, TIM_CHANNEL_1, brightness); // LED on PA5



                HAL_Delay(delay_ms); // Adjust delay for breathing speed

              }



              // Ensure brightness is exactly 0 after loop

              __HAL_TIM_SET_COMPARE(&htim1, TIM_CHANNEL_2, 0);

              __HAL_TIM_SET_COMPARE(&htim2, TIM_CHANNEL_1, 0);

              HAL_Delay(delay_ms * 10); // Optional: Pause briefly when off



              /* USER CODE END 3 */

            }

    /* USER CODE BEGIN 3 */

  }

  /* USER CODE END 3 */