HAL库学习梳理——UART
笔者跟着B站铁头山羊视频学习 STM32-HAL库 开发教程。下面对HAL库有关UART课程知识和应用做一个梳理。
省流：
uint8_t byteNumber = 0x5a;
uint8_t byteArray[] = {0,1,2,3,4,5};
char ch = 'a';
char *str = "Hello word";
HAL_UART_Transmit(&huart1,&byteNumber,1,HAL_MAX_DELAY); // 发送一个字节
HAL_UART_Transmit(&huart1,byteArray,6,HAL_MAX_DELAY); // 发送一个多个字节
HAL_UART_Transmit(&huart1,(uint8_t *)&ch,1,HAL_MAX_DELAY); // 发送一个字符
HAL_UART_Transmit(&huart1,(uint8_t *)str,strlen(str),HAL_MAX_DELAY); // 发送一个字符串发送数据给 串口外设。
uint8_t Data_Receive;
HAL_UART_Receive(&huart1,&Data_Receive,1,HAL_MAX_DELAY);
if(Data_Receive == 0)
{
HAL_GPIO_WritePin(GPIOC,GPIO_PIN_13,GPIO_PIN_RESET);
}
将串口接收到的数据保存到自定义的变量中，再判断。
1、串口UART基本原理
常用8位无校验的数据帧格式：1 个起始位、1 个停止位、8个数据位。
2、示例
2.1 简单数据传输
（1） GPIO引脚配置
将PA9发送引脚设置为复用推挽输出，系统自动配置。
将PA9发送引脚设置为输入模式。手动配置上拉电阻使能，以防这个引脚意外断开，像按键一样。
（2）UART参数配置
选择异步模式（Asynchronus），对下面的参数设置（Parameter Setting）进行配置。
（3）程序
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();
/* USER CODE BEGIN 2 */
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
HAL_GPIO_WritePin(GPIOC, GPIO_PIN_13, GPIO_PIN_RESET); // 点亮LED，C13置0，开漏输出低电压
HAL_GPIO_WritePin(GPIOA, GPIO_PIN_9, GPIO_PIN_SET); // 点亮LED，C9置1，推挽输出高电压
HAL_Delay(500);
HAL_GPIO_WritePin(GPIOC, GPIO_PIN_13, GPIO_PIN_SET); // 熄灭LED，C13置1，开漏输出高阻态
HAL_GPIO_WritePin(GPIOA, GPIO_PIN_9, GPIO_PIN_RESET); // 熄灭LED，C9置0，推挽输出低电压
HAL_Delay(500);
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}
2.2 通过串口发送命令点亮LED灯
（1） UART参数配置
（2）程序
int main(void)
{
/* USER CODE BEGIN 1 */
uint8_t byteNumber = 0x5a;
uint8_t byteArray[] = {0,1,2,3,4,5};
char ch = 'a';
char *str = "Hello word";
HAL_UART_Transmit(&huart1,&byteNumber,1,HAL_MAX_DELAY);
HAL_UART_Transmit(&huart1,byteArray,6,HAL_MAX_DELAY);
HAL_UART_Transmit(&huart1,(uint8_t *)&ch,1,HAL_MAX_DELAY);
HAL_UART_Transmit(&huart1,(uint8_t *)str,strlen(str),HAL_MAX_DELAY);
/* 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 */
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
char *Data_Receive;
HAL_UART_Receive(&huart1,(uint8_t *)Data_Receive,sizeof(Data_Receive),HAL_MAX_DELAY); // 接收UART数据保存到Data_Receive
if( strncmp(Data_Receive,"on",2)==0) // 判断
{
HAL_GPIO_WritePin(GPIOC,GPIO_PIN_13,GPIO_PIN_RESET); // 点灯
}
else if( strncmp(Data_Receive,"off",3)==0)
{
HAL_GPIO_WritePin(GPIOC,GPIO_PIN_13,GPIO_PIN_SET);
}
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}