使用STM32的串口通讯,接收串口助手的数据,并且将接收到的数据返回串口,重定义printf功能。
配置引脚信息
由于每次新建工程都需要配置信息,比较麻烦,好在STM32CubeIDE提供了导入.ioc文件的功能,可以帮我们节省时间。
1.从BEEP的项目里导入ioc文件,并命名为Serial。
将串口1的mode修改为Asynchronous同步通讯,波特率为115200,数据宽度:8位,检验:None,停止位:1位。
2.添加DMA发送通道
3.打开串口1中断设置。
核心代码解释
1.在BSP中新建蜂鸣器的驱动库bsp_uart.h和bsp_uart.c文件。在bsp_uart.h中增加以下内容:
/** bsp_uart.h** Created on: Mar 4, 2022* Author: Administrator*/#ifndef BSP_UART_H_
#define BSP_UART_H_#include "stdint.h"void USART1_Init(void);
void USART1_Send_U8(uint8_t ch);
void USART1_Send_ArrayU8(uint8_t *BufferPtr, uint16_t Length);#endif /* BSP_UART_H_ */
2.在bsp_uart.c中添加以下内容:
/** bsp_uart.c** Created on: Mar 4, 2022* Author: Administrator*/#include "bsp_uart.h"
#include "bsp.h"#define ENABLE_UART_DMA 1uint8_t RxTemp = 0;// Initialize USART1 初始化串口1
void USART1_Init(void)
{HAL_UART_Receive_IT(&huart1, (uint8_t *)&RxTemp, 1);
}// The serial port sends one byte 串口发送一个字节
void USART1_Send_U8(uint8_t ch)
{HAL_UART_Transmit(&huart1, (uint8_t *)&ch, 1, 0xFFFF);
}// The serial port sends a string of data 串口发送一串数据
void USART1_Send_ArrayU8(uint8_t *BufferPtr, uint16_t Length)
{#if ENABLE_UART_DMAHAL_UART_Transmit_DMA(&huart1, BufferPtr, Length);#elsewhile (Length--){USART1_Send_U8(*BufferPtr);BufferPtr++;}#endif
}// The serial port receiving is interrupted. Procedure 串口接收完成中断
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{/* Prevent unused argument(s) compilation warning */UNUSED(huart);/* NOTE : This function should not be modified, when the callback is needed,the HAL_UART_RxCpltCallback can be implemented in the user file*/// 测试发送数据,实际应用中不应该在中断中发送数据// Test sending data. In practice, data should not be sent during interrupts USART1_Send_U8(RxTemp);// Continue receiving data 继续接收数据HAL_UART_Receive_IT(&huart1, (uint8_t *)&RxTemp, 1);
}#ifdef __GNUC__
#define PUTCHAR_PROTOTYPE int __io_putchar(int ch)
#else
#define PUTCHAR_PROTOTYPE int fputc(int ch, FILE *f)
#endif /* __GNUC__ */
PUTCHAR_PROTOTYPE
{/* Place your implementation of fputc here *//* e.g. write a character to the EVAL_COM1 and Loop until the end of transmission */HAL_UART_Transmit(&huart1, (uint8_t *)&ch, 1, 0xFFFF);return ch;
}
USART1_Init():初始化串口相关内容,开启串口接收1个数据。
USART1_Send_U8(ch):串口1发送一个字节。
USART1_Send_ArrayU8(BufferPtr,Length):串口1发送一串数据,BufferPtr是数据的首地址,Length是数据的长度。ENABLE_UART_DMA是串口1 DMA的开关。
3.由于串口1接收中断只进行一次,所以接收数据后需要再次调用接收数据。这里为了方便测试,所以在中断调用串口发送数据,实际应用中不应该在中断中发送数据,串口发送数据比较耗时,可能导致丢包甚至串口出错等问题。
4.重新定义printf使用串口1发送数据。
5.在BSP初始化中,调用USART1_Init()函数,请求接收数据。
//bsp.c
#include "bsp.h"// LED显示当前运行状态,每10毫秒调用一次,LED灯每200毫秒闪烁一次。
// The LED displays the current operating status, which is invoked every 10 milliseconds, and the LED blinks every 200 milliseconds.
static void Bsp_Led_Show_State_Handle(void)
{static uint8_t led_count = 0;led_count++;if (led_count > 20){led_count = 0;LED_TOGGLE();}
}// The peripheral device is initialized 外设设备初始化
void Bsp_Init(void)
{Beep_On_Time(50);USART1_Init();
}// main.c中循环调用此函数,避免多次修改main.c文件。
// This function is called in a loop in main.c to avoid multiple modifications to the main.c file
void Bsp_Loop(void)
{// Detect button down events 检测按键按下事件if (Key1_State(KEY_MODE_ONE_TIME)){Beep_On_Time(50);static int press = 0;press++;printf("press:%d\n", press);}Bsp_Led_Show_State_Handle();// The buzzer automatically shuts down when times out 蜂鸣器超时自动关闭Beep_Timeout_Close_Handle();HAL_Delay(10);
}
6.在按键按下后,增加printf()函数,通过串口1打印信息。
/* USER CODE BEGIN Header */
/********************************************************************************* @file : main.c* @brief : Main program body******************************************************************************* @attention** Copyright (c) 2022 STMicroelectronics.* All rights reserved.** This software is licensed under terms that can be found in the LICENSE file* in the root directory of this software component.* If no LICENSE file comes with this software, it is provided AS-IS.********************************************************************************/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "dma.h"
#include "usart.h"
#include "gpio.h"/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "bsp.h"
/* USER CODE END Includes *//* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD *//* USER CODE END PTD *//* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* USER CODE END PD *//* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM *//* USER CODE END PM *//* Private variables ---------------------------------------------------------*//* USER CODE BEGIN PV *//* USER CODE END PV *//* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP *//* USER CODE END PFP *//* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 *//* USER CODE END 0 *//*** @brief The application entry point.* @retval int*/
int main(void)
{/* USER CODE BEGIN 1 *//* USER CODE END 1 *//* MCU Configuration--------------------------------------------------------*//* Reset of all peripherals, Initializes the Flash interface and the Systick. */HAL_Init();/* USER CODE BEGIN Init *//* USER CODE END Init *//* Configure the system clock */SystemClock_Config();/* USER CODE BEGIN SysInit *//* USER CODE END SysInit *//* Initialize all configured peripherals */MX_GPIO_Init();MX_DMA_Init();MX_USART1_UART_Init();/* USER CODE BEGIN 2 */Bsp_Init();/* USER CODE END 2 *//* Infinite loop *//* USER CODE BEGIN WHILE */while (1){Bsp_Loop();/* USER CODE END WHILE *//* USER CODE BEGIN 3 */}/* USER CODE END 3 */
}/*** @brief System Clock Configuration* @retval None*/
void SystemClock_Config(void)
{RCC_OscInitTypeDef RCC_OscInitStruct = {0};RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};/** Initializes the RCC Oscillators according to the specified parameters* in the RCC_OscInitTypeDef structure.*/RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;RCC_OscInitStruct.HSEState = RCC_HSE_ON;RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;RCC_OscInitStruct.HSIState = RCC_HSI_ON;RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9;if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK){Error_Handler();}/** Initializes the CPU, AHB and APB buses clocks*/RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK){Error_Handler();}
}/* USER CODE BEGIN 4 *//* USER CODE END 4 *//*** @brief This function is executed in case of error occurrence.* @retval None*/
void Error_Handler(void)
{/* USER CODE BEGIN Error_Handler_Debug *//* User can add his own implementation to report the HAL error return state */__disable_irq();while (1){}/* USER CODE END Error_Handler_Debug */
}#ifdef USE_FULL_ASSERT
/*** @brief Reports the name of the source file and the source line number* where the assert_param error has occurred.* @param file: pointer to the source file name* @param line: assert_param error line source number* @retval None*/
void assert_failed(uint8_t *file, uint32_t line)
{/* USER CODE BEGIN 6 *//* User can add his own implementation to report the file name and line number,ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) *//* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
实验效果
烧录程序后,LED灯每隔200毫秒闪一次,将扩展板通过micro-USB数据线与电脑连接后并打开串口助手(具体参数如下图所示),每按一次按键,蜂鸣器都会响50毫秒,可以看到串口助手会显示press:xx,每按一次按键xx自动加1。串口助手发送字符a,扩展板会自动将字符a返回。由于上面使用在中断中发送数据,所以不能一次发送太多个字符,否则会出现字符丢失甚至串口错误。