[嵌入式]Stm32L0 STM32CUBE中UART和使用LPUART1以及串口不进中断问题解决

使用STM32CUBE配置串口USART2

?USART2中断

使用STM32CUBE配置串口LPUART1，这个串口要配置115200可能需要修改时钟，太低的系统时钟可能无法达到这个速度

配置中断LPUART1

?GPIO设置一般默认就可以

?都使用LL库

生成代码，此处很关键，默认生成的代码里没有使能LPUART1，需要手动使能，官方应该是出于功耗考虑，但是新手就在此掉坑了

/**
  ******************************************************************************
  * @file    usart.c
  * @brief   This file provides code for the configuration
  *          of the USART instances.
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; Copyright (c) 2021 STMicroelectronics.
  * All rights reserved.</center></h2>
  *
  * This software component is licensed by ST under BSD 3-Clause license,
  * the "License"; You may not use this file except in compliance with the
  * License. You may obtain a copy of the License at:
  *                        opensource.org/licenses/BSD-3-Clause
  *
  ******************************************************************************
  */

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

/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

/* LPUART1 init function */

void MX_LPUART1_UART_Init(void)
{

  /* USER CODE BEGIN LPUART1_Init 0 */

  /* USER CODE END LPUART1_Init 0 */

  LL_LPUART_InitTypeDef LPUART_InitStruct = {0};

  LL_GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* Peripheral clock enable */
  LL_APB1_GRP1_EnableClock(LL_APB1_GRP1_PERIPH_LPUART1);

  LL_IOP_GRP1_EnableClock(LL_IOP_GRP1_PERIPH_GPIOA);
  /**LPUART1 GPIO Configuration
  PA2   ------> LPUART1_TX
  PA3   ------> LPUART1_RX
  */
  GPIO_InitStruct.Pin = LL_GPIO_PIN_2;
  GPIO_InitStruct.Mode = LL_GPIO_MODE_ALTERNATE;
  GPIO_InitStruct.Speed = LL_GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.OutputType = LL_GPIO_OUTPUT_PUSHPULL;
  GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
  GPIO_InitStruct.Alternate = LL_GPIO_AF_6;
  LL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  GPIO_InitStruct.Pin = LL_GPIO_PIN_3;
  GPIO_InitStruct.Mode = LL_GPIO_MODE_ALTERNATE;
  GPIO_InitStruct.Speed = LL_GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.OutputType = LL_GPIO_OUTPUT_PUSHPULL;
  GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
  GPIO_InitStruct.Alternate = LL_GPIO_AF_6;
  LL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /* LPUART1 interrupt Init */
  NVIC_SetPriority(LPUART1_IRQn, 0);
  NVIC_EnableIRQ(LPUART1_IRQn);

  /* USER CODE BEGIN LPUART1_Init 1 */

  /* USER CODE END LPUART1_Init 1 */
  LPUART_InitStruct.BaudRate = 9600;
  LPUART_InitStruct.DataWidth = LL_LPUART_DATAWIDTH_8B;
  LPUART_InitStruct.StopBits = LL_LPUART_STOPBITS_1;
  LPUART_InitStruct.Parity = LL_LPUART_PARITY_NONE;
  LPUART_InitStruct.TransferDirection = LL_LPUART_DIRECTION_TX_RX;
  LPUART_InitStruct.HardwareFlowControl = LL_LPUART_HWCONTROL_NONE;
  LL_LPUART_Init(LPUART1, &LPUART_InitStruct);
  /* USER CODE BEGIN LPUART1_Init 2 */

  /* USER CODE END LPUART1_Init 2 */

}
/* USART2 init function */

void MX_USART2_UART_Init(void)
{

  /* USER CODE BEGIN USART2_Init 0 */

  /* USER CODE END USART2_Init 0 */

  LL_USART_InitTypeDef USART_InitStruct = {0};

  LL_GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* Peripheral clock enable */
  LL_APB1_GRP1_EnableClock(LL_APB1_GRP1_PERIPH_USART2);

  LL_IOP_GRP1_EnableClock(LL_IOP_GRP1_PERIPH_GPIOA);
  /**USART2 GPIO Configuration
  PA9   ------> USART2_TX
  PA10   ------> USART2_RX
  */
  GPIO_InitStruct.Pin = LL_GPIO_PIN_9;
  GPIO_InitStruct.Mode = LL_GPIO_MODE_ALTERNATE;
  GPIO_InitStruct.Speed = LL_GPIO_SPEED_FREQ_HIGH;
  GPIO_InitStruct.OutputType = LL_GPIO_OUTPUT_PUSHPULL;
  GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
  GPIO_InitStruct.Alternate = LL_GPIO_AF_4;
  LL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  GPIO_InitStruct.Pin = LL_GPIO_PIN_10;
  GPIO_InitStruct.Mode = LL_GPIO_MODE_ALTERNATE;
  GPIO_InitStruct.Speed = LL_GPIO_SPEED_FREQ_HIGH;
  GPIO_InitStruct.OutputType = LL_GPIO_OUTPUT_PUSHPULL;
  GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
  GPIO_InitStruct.Alternate = LL_GPIO_AF_4;
  LL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /* USART2 interrupt Init */
  NVIC_SetPriority(USART2_IRQn, 0);
  NVIC_EnableIRQ(USART2_IRQn);

  /* USER CODE BEGIN USART2_Init 1 */

  /* USER CODE END USART2_Init 1 */
  USART_InitStruct.BaudRate = 115200;
  USART_InitStruct.DataWidth = LL_USART_DATAWIDTH_8B;
  USART_InitStruct.StopBits = LL_USART_STOPBITS_1;
  USART_InitStruct.Parity = LL_USART_PARITY_NONE;
  USART_InitStruct.TransferDirection = LL_USART_DIRECTION_TX_RX;
  USART_InitStruct.HardwareFlowControl = LL_USART_HWCONTROL_NONE;
  USART_InitStruct.OverSampling = LL_USART_OVERSAMPLING_16;
  LL_USART_Init(USART2, &USART_InitStruct);
  LL_USART_DisableOverrunDetect(USART2);
  LL_USART_DisableDMADeactOnRxErr(USART2);
  LL_USART_ConfigAsyncMode(USART2);
  LL_USART_Enable(USART2);
  /* USER CODE BEGIN USART2_Init 2 */

  /* USER CODE END USART2_Init 2 */

}

/* USER CODE BEGIN 1 */

/* USER CODE END 1 */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

?使能LPUART1代码

  /* USER CODE BEGIN LPUART1_Init 2 */
  LL_USART_DisableOverrunDetect(LPUART1);
  LL_USART_DisableDMADeactOnRxErr(LPUART1);
  LL_USART_ConfigAsyncMode(LPUART1);
	LL_USART_Enable(LPUART1);
  /* USER CODE END LPUART1_Init 2 */

切记，这样串口是不会进中断的，?STM32CUBE默认不给开启中断，就说是不是坑

?? ?/* 开启串口1中断 */
? LL_USART_EnableIT_RXNE(LPUART1);
?? ?/* 开启串口2中断 */
? LL_USART_EnableIT_RXNE(USART2);