会自动在tim.c里面生成代码，如下：

/* Includes ------------------------------------------------------------------*/
#include "tim.h"

/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

TIM_HandleTypeDef htim17;

/* TIM17 init function */
void MX_TIM17_Init(void)
{

htim17.Instance = TIM17;
htim17.Init.Prescaler = 0;
htim17.Init.CounterMode = TIM_COUNTERMODE_UP;
htim17.Init.Period = 65535;
htim17.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
htim17.Init.RepetitionCounter = 0;
if (HAL_TIM_Base_Init(&htim17) != HAL_OK)
{
Error_Handler();
}

}

void HAL_TIM_Base_MspInit(TIM_HandleTypeDef* tim_baseHandle)
{

if(tim_baseHandle->Instance==TIM17)
{
/* USER CODE BEGIN TIM17_MspInit 0 */

/* USER CODE END TIM17_MspInit 0 */
/* Peripheral clock enable */
__HAL_RCC_TIM17_CLK_ENABLE();
/* USER CODE BEGIN TIM17_MspInit 1 */

/* USER CODE END TIM17_MspInit 1 */
}
}

void HAL_TIM_Base_MspDeInit(TIM_HandleTypeDef* tim_baseHandle)
{

if(tim_baseHandle->Instance==TIM17)
{
/* USER CODE BEGIN TIM17_MspDeInit 0 */

/* USER CODE END TIM17_MspDeInit 0 */
/* Peripheral clock disable */
__HAL_RCC_TIM17_CLK_DISABLE();
}
/* USER CODE BEGIN TIM17_MspDeInit 1 */

/* USER CODE END TIM17_MspDeInit 1 */
}

然后自己再写一个函数;

/* USER CODE BEGIN 4 */

void Delay_us(uint16_t nus)
{
__HAL_TIM_SetCounter(&htim17, 0);//htim17

__HAL_TIM_ENABLE(&htim17);

while(__HAL_TIM_GetCounter(&htim17) < (36 * nus));//36是系统时钟，更改这里就行了。
/* Disable the Peripheral */
__HAL_TIM_DISABLE(&htim17);
}

/* USER CODE END 4 */

因为36 * 1/36M 对应的就是1us，用定时器来做延时是很准的。

STM32 CubeMX如何生成微秒(us)级延时