将GPIO的速度等级设置为最低也可以一定程度上降低功耗

eric2013

void HAL_LPTIM_MspInit(LPTIM_HandleTypeDef *hlptim)
{
  GPIO_InitTypeDef     GPIO_InitStruct;

  /* ## - 1 - Enable LPTIM clock ############################################ */
  __HAL_RCC_LPTIM1_CLK_ENABLE();

  /* ## - 2 - Force & Release the LPTIM Periheral Clock Reset ############### */
  /* Force the LPTIM Periheral Clock Reset */
  __HAL_RCC_LPTIM1_FORCE_RESET();

  /* Release the LPTIM Periheral Clock Reset */
  __HAL_RCC_LPTIM1_RELEASE_RESET();

  /* ## - 3 - Enable & Configure LPTIM Ultra Low Power ################# */
  /* Configure PD.13 (LPTIM1_OUT) in alternate function (AF1), Low speed
  push-pull mode and pull-up enabled.
Note: In order to reduce power consumption: GPIO Speed is configured in  <-----------------------------------------
  LowSpeed */

  /* Enable GPIO PORT */
  __HAL_RCC_GPIOD_CLK_ENABLE();

  /* Configure PD.13 */
  GPIO_InitStruct.Pin = GPIO_PIN_13;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_PULLUP;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_MEDIUM;
  GPIO_InitStruct.Alternate = GPIO_AF1_LPTIM1;
  HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);
}