STM32对HAL库的串口不定长度的读写操作（一）
这几天终于开始接触HAL库，随着固件库被逐渐淘汰，尽管很多人说用STM32CUBEMX不能很好地学习stm32，但这肯定是一个趋势，所以用好HAL库十分得重要。
这几天也学到了简单地操作cubemx这个软件，这里不做教学，因为百度很多，虽然很杂乱，但是总能找到的。HAL库的应用与固件库在一些特定函数上不一样。举几个我目前遇到的例子。
再弄跑马灯时需要用到翻转的程序，HAL库有自带的翻转函数，使用方便。
延时函数也有自带。
串口读写，个人理解来说，串口分为三种，1、普通的串口写入 2、串口中断的读和写 3、串口中断与DMA
现在还没接触到DMA，后续再补上。
1、普通的串口写入，
HAL库有特定函数将数据传入特定的串口，用上位机软件即可读到函数传输的数据。
2、串口中断的读和写
/* USER CODE BEGIN Header */ /** ****************************************************************************** * @file : main.c * @brief : Main program body ****************************************************************************** * @attention * * <h2><center>© Copyright (c) 2019 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 * ****************************************************************************** */ /* USER CODE END Header */ /* Includes ------------------------------------------------------------------*/ #include "main.h" /* Private includes ----------------------------------------------------------*/ /* USER CODE BEGIN Includes */ /* 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 ---------------------------------------------------------*/ UART_HandleTypeDef huart1; /* USER CODE BEGIN PV */ /* USER CODE END PV */ /* Private function prototypes -----------------------------------------------*/ void SystemClock_Config(void); static void MX_GPIO_Init(void); static void MX_USART1_UART_Init(void); /* USER CODE BEGIN PFP */ /* USER CODE END PFP */ /* Private user code ---------------------------------------------------------*/ /* USER CODE BEGIN 0 */ uint8_t dd[10]; //uint8_t dd; uint8_t ff[]="send!"; /* 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_USART1_UART_Init(); /* USER CODE BEGIN 2 */ uint8_t aa[] = "key0"; uint8_t bb[] = "key1"; uint8_t cc[] = "wkup_pres"; //uint8_t dd[20]; /* USER CODE END 2 */ /* Infinite loop */ /* USER CODE BEGIN WHILE */ HAL_UART_Receive_IT(&huart1, dd, 1); while (1) { int key = 0; key=KEY_Scan(0); /* USER CODE END WHILE */ /* USER CODE BEGIN 3 */ switch(key) { case KEY0_PRES: //LED0=!LED0; HAL_GPIO_TogglePin(GPIOA, GPIO_PIN_8); HAL_UART_Transmit(&huart1, aa, sizeof(aa), 0xffff); break; case KEY1_PRES: // LED1=!LED1; HAL_GPIO_TogglePin(GPIOD, GPIO_PIN_2); HAL_UART_Transmit(&huart1, bb, sizeof(bb), 0xffff); break; case WKUP_PRES: // LED0=!LED0; // LED1=!LED1; HAL_GPIO_TogglePin(GPIOA, GPIO_PIN_8); HAL_GPIO_TogglePin(GPIOD, GPIO_PIN_2); HAL_UART_Transmit(&huart1, cc, sizeof(cc), 0xffff); //HAL_Delay(100); //HAL_UART_Transmit(&huart1, cc, sizeof(cc), 0xffff); // HAL_UART_Transmit(&huart1, aa, sizeof(aa), 0xffff); // HAL_UART_Transmit(&huart1, bb, sizeof(bb), 0xffff); break; default: HAL_Delay(10); } //HAL_UART_Receive_IT(&huart1, dd, 1); } /* 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 CPU, AHB and APB busses clocks */ RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI; RCC_OscInitStruct.HSIState = RCC_HSI_ON; RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT; RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE; if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) { Error_Handler(); } /** Initializes the CPU, AHB and APB busses clocks */ RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2; RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI; RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1; RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1; RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1; if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK) { Error_Handler(); } } /** * @brief USART1 Initialization Function * @param None * @retval None */ static void MX_USART1_UART_Init(void) { /* USER CODE BEGIN USART1_Init 0 */ /* USER CODE END USART1_Init 0 */ /* USER CODE BEGIN USART1_Init 1 */ /* USER CODE END USART1_Init 1 */ huart1.Instance = USART1; huart1.Init.BaudRate = 9600; huart1.Init.WordLength = UART_WORDLENGTH_8B; huart1.Init.StopBits = UART_STOPBITS_1; huart1.Init.Parity = UART_PARITY_NONE; huart1.Init.Mode = UART_MODE_TX_RX; huart1.Init.HwFlowCtl = UART_HWCONTROL_NONE; huart1.Init.OverSampling = UART_OVERSAMPLING_16; if (HAL_UART_Init(&huart1) != HAL_OK) { Error_Handler(); } /* USER CODE BEGIN USART1_Init 2 */ /* USER CODE END USART1_Init 2 */ } /** * @brief GPIO Initialization Function * @param None * @retval None */ static void MX_GPIO_Init(void) { GPIO_InitTypeDef GPIO_InitStruct = {0}; /* GPIO Ports Clock Enable */ __HAL_RCC_GPIOD_CLK_ENABLE(); __HAL_RCC_GPIOA_CLK_ENABLE(); __HAL_RCC_GPIOC_CLK_ENABLE(); /*Configure GPIO pin Output Level */ HAL_GPIO_WritePin(GPIOA, GPIO_PIN_8, GPIO_PIN_RESET); /*Configure GPIO pin Output Level */ HAL_GPIO_WritePin(GPIOD, GPIO_PIN_2, GPIO_PIN_RESET); /*Configure GPIO pin : WK_UP_Pin */ GPIO_InitStruct.Pin = WK_UP_Pin; GPIO_InitStruct.Mode = GPIO_MODE_INPUT; GPIO_InitStruct.Pull = GPIO_PULLDOWN; HAL_GPIO_Init(WK_UP_GPIO_Port, &GPIO_InitStruct); /*Configure GPIO pin : KEY0_Pin */ GPIO_InitStruct.Pin = KEY0_Pin; GPIO_InitStruct.Mode = GPIO_MODE_INPUT; GPIO_InitStruct.Pull = GPIO_PULLUP; HAL_GPIO_Init(KEY0_GPIO_Port, &GPIO_InitStruct); /*Configure GPIO pin : PA8 */ GPIO_InitStruct.Pin = GPIO_PIN_8; GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP; GPIO_InitStruct.Pull = GPIO_NOPULL; GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH; HAL_GPIO_Init(GPIOA, &GPIO_InitStruct); /*Configure GPIO pin : KEY1_Pin */ GPIO_InitStruct.Pin = KEY1_Pin; GPIO_InitStruct.Mode = GPIO_MODE_INPUT; GPIO_InitStruct.Pull = GPIO_PULLUP; HAL_GPIO_Init(KEY1_GPIO_Port, &GPIO_InitStruct); /*Configure GPIO pin : PD2 */ GPIO_InitStruct.Pin = GPIO_PIN_2; GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP; GPIO_InitStruct.Pull = GPIO_NOPULL; GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH; HAL_GPIO_Init(GPIOD, &GPIO_InitStruct); } /* USER CODE BEGIN 4 */ int KEY_Scan(int mode) { static int key_up=1;//按键按松开标志 if(mode) key_up=1; //支持连按 if(key_up&&(KEY0==0||KEY1==0||WK_UP==1)) { HAL_Delay(10);//去抖动 key_up=0; if(KEY0==0)return KEY0_PRES; else if(KEY1==0)return KEY1_PRES; else if(WK_UP==1)return WKUP_PRES; }else if(KEY0==1&&KEY1==1&&WK_UP==0)key_up=1; return 0;// 无按键按下 } void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart) { UNUSED(huart); HAL_UART_Transmit(&huart1, dd, 1, 0xffff); HAL_UART_Receive_IT(&huart1,dd, 1); //memset(dd, 0x00, sizeof(dd)); } /* 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 */ /* 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, tex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */ /* USER CODE END 6 */ } #endif /* USE_FULL_ASSERT */ /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
这里插入串口读写的main文件，程序先无视按键KEY的作用，直接看到
在串口接收外部如上位机发送的数据时需要用HAL库的这个函数接收数据，可设置特定的串口和接收到哪个位置，以及接收数据的长度。若你直接把接收的数据transmit 出去，也可以做到，但是得是定长度的读写操作，不然会出现溢出或者是数据缺失的现象。
今天遇到这个问题，百度找了很多相关的，大多方法都特别复杂，很多也是通过DMA来解决的，后来发现一中方法。在receive_IT执行完毕后，会进入一个回调函数（需要自己重新声明出来），
若在回调函数中发送其中一个字节，在接收，又会调用这个回调函数，反复之后就可以把读到的数据全部放入dd 中，最后发给串口。这种递归思想很好，实现了不定长度的读写。
对于这个回调函数和中断函数的区别没怎么分清，串口中断函数可能多用于执行其他操作吧，回调函数多用于此读取操作吧，个人猜测。
在（二）中简单解析个人写的C#上位机软件，与stm32实现数据读写操作。
