USART3 外接 RS485
UART7 外接 RS232
//USART支持同步传输，UART只支持异步传输，其他一样，备注一下
//本例程都做异步传输
1-5步在main.c文件中
1、STM32CubeMX自动生成
UART_HandleTypeDef huart7;
UART_HandleTypeDef huart3;
2、新增接收缓冲区
u8 aRxBuffer_uart3[64]={0};
u8 aRxBuffer_uart7[64]={0};
3、STM32CubeMX自动生成
static void MX_UART7_Init(void);
static void MX_USART3_UART_Init(void);
4、STM32CubeMX自动生成
int main(void)
{
......
MX_UART7_Init();
MX_USART3_UART_Init();
......
}
5、STM32CubeMX自动生成
static void MX_UART7_Init(void)
{
/* USER CODE BEGIN UART7_Init 0 */
/* USER CODE END UART7_Init 0 */
/* USER CODE BEGIN UART7_Init 1 */
/* USER CODE END UART7_Init 1 */
huart7.Instance = UART7;
huart7.Init.BaudRate = 115200;
huart7.Init.WordLength = UART_WORDLENGTH_8B;
huart7.Init.StopBits = UART_STOPBITS_1;
huart7.Init.Parity = UART_PARITY_NONE;
huart7.Init.Mode = UART_MODE_TX_RX;
huart7.Init.HwFlowCtl = UART_HWCONTROL_NONE;
huart7.Init.OverSampling = UART_OVERSAMPLING_16;
if (HAL_UART_Init(&huart7) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN UART7_Init 2 */
HAL_UART_Receive_IT(&huart7, (u8 *)aRxBuffer_uart7, 1);**//开启接收中断，如果没有自动生成就要自己加入**
/* USER CODE END UART7_Init 2 */
}
static void MX_USART3_UART_Init(void)
{
/* USER CODE BEGIN USART3_Init 0 */
/* USER CODE END USART3_Init 0 */
/* USER CODE BEGIN USART3_Init 1 */
/* USER CODE END USART3_Init 1 */
huart3.Instance = USART3;
huart3.Init.BaudRate = 115200;
huart3.Init.WordLength = UART_WORDLENGTH_8B;
huart3.Init.StopBits = UART_STOPBITS_1;
huart3.Init.Parity = UART_PARITY_NONE;
huart3.Init.Mode = UART_MODE_TX_RX;
huart3.Init.HwFlowCtl = UART_HWCONTROL_NONE;
huart3.Init.OverSampling = UART_OVERSAMPLING_16;
if (HAL_UART_Init(&huart3) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN USART3_Init 2 */
HAL_UART_Receive_IT(&huart3, (u8 *)aRxBuffer_uart3, 1);// 即Size设置为1，只接收1Byte数据，在每次中断结束后重新配置来使能中断。
/* USER CODE END USART3_Init 2 */
}
6、STM32CubeMX自动生成,如果没有自己加入
stm32f4xx.hal.msp.c文件中
void HAL_UART_MspInit(UART_HandleTypeDef* huart)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
if(huart->Instance==UART7)
{
......
/* USER CODE BEGIN UART7_MspInit 1 */
HAL_NVIC_SetPriority(UART7_IRQn, 3, 3);//设置中断
HAL_NVIC_EnableIRQ(UART7_IRQn);;//设置中断
/* USER CODE END UART7_MspInit 1 */
}
else if(huart->Instance==USART3)
{
......
/* USART3 interrupt Init */
HAL_NVIC_EnableIRQ(USART3_IRQn);//设置中断
HAL_NVIC_SetPriority(USART3_IRQn, 3, 3);//设置中断
}
}
void HAL_UART_MspDeInit(UART_HandleTypeDef* huart)函数中如果没有自动生成，加入：
HAL_NVIC_DisableIRQ(UART7_IRQn);
HAL_NVIC_DisableIRQ(USART3_IRQn);
这个不是必须的，不写也不影响.
void HAL_UART_MspDeInit(UART_HandleTypeDef* huart)
{
if(huart->Instance==UART7)
{
/* USER CODE BEGIN UART7_MspDeInit 0 */
/* USER CODE END UART7_MspDeInit 0 */
/* Peripheral clock disable */
__HAL_RCC_UART7_CLK_DISABLE();
/**UART7 GPIO Configuration
PF6 ------> UART7_RX
PF7 ------> UART7_TX
*/
HAL_GPIO_DeInit(GPIOF, GPIO_PIN_6|GPIO_PIN_7);
/* USER CODE BEGIN UART7_MspDeInit 1 */
HAL_NVIC_DisableIRQ(UART7_IRQn); //初始化关中断
/* USER CODE END UART7_MspDeInit 1 */
}
else if(huart->Instance==USART3)
{
/* USER CODE BEGIN USART3_MspDeInit 0 */
/* USER CODE END USART3_MspDeInit 0 */
/* Peripheral clock disable */
__HAL_RCC_USART3_CLK_DISABLE();
/**USART3 GPIO Configuration
PC10 ------> USART3_TX
PC11 ------> USART3_RX
*/
HAL_GPIO_DeInit(GPIOC, GPIO_PIN_10|GPIO_PIN_11);
/* USART3 interrupt DeInit */
HAL_NVIC_DisableIRQ(USART3_IRQn); //初始化关中断
/* USER CODE BEGIN USART3_MspDeInit 1 */
/* USER CODE END USART3_MspDeInit 1 */
}
}
7、STM32CubeMX自动生成,如果没有自己加入
stm32f4xx.it.c文件中
extern UART_HandleTypeDef huart3;
extern UART_HandleTypeDef huart7;
void USART3_IRQHandler(void)
{
/* USER CODE BEGIN USART3_IRQn 0 */
/* USER CODE END USART3_IRQn 0 */
HAL_UART_IRQHandler(&huart3);
/* USER CODE BEGIN USART3_IRQn 1 */
/* USER CODE END USART3_IRQn 1 */
}
/* USER CODE BEGIN 1 */
void UART7_IRQHandler(void)
{
/* USER CODE BEGIN USART3_IRQn 0 */
/* USER CODE END USART3_IRQn 0 */
HAL_UART_IRQHandler(&huart7);
/* USER CODE BEGIN USART3_IRQn 1 */
/* USER CODE END USART3_IRQn 1 */
}
8、重写接收中断回调函数，测试
main.c中
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
static int a=0;
a++;
// printf("%d",a);
if(huart->Instance==USART3)
{
printf("USART3 %d..%d\n",a,aRxBuffer_uart3[0]);
HAL_UART_Receive_IT(&huart3, (uint8_t *)aRxBuffer_uart3, 1);//重开中断
}
if(huart->Instance==UART7)
{
printf("UART7 %d..%d\n",a,aRxBuffer_uart7[0]);
HAL_UART_Receive_IT(&huart7, (uint8_t *)aRxBuffer_uart7, 1);//重开中断
}
}
9、发送测试，这段代码可以放在main.c文件main()函数while(1){}中，或其他定时或外部中断函数中测试
static int TEAT_num=0;
TEAT_num++;
// printf("ttest = %x\n", TEAT_num);//测试OK
RS485_OUT=1;//485输出
delay_us(20);//10us会有错误，485外部硬件电路不同，延时时间可能不同
HAL_UART_Transmit(&huart3, (uint8_t *)&TEAT_num, 1, 0xFFFF);//huart3 485
while(__HAL_UART_GET_FLAG(&huart3,UART_FLAG_TC)!=SET);//等待发送完成
RS485_OUT=0;//485输入
HAL_UART_Transmit(&huart7, (uint8_t *)&TEAT_num, 4, 0xFFFF);//huart7 串口
while(__HAL_UART_GET_FLAG(&huart7,UART_FLAG_TC)!=SET);//等待发送完成
10、如果用printf 打印输出数据
则重定义int fputc(int ch, FILE *f)；函数
//int fputc(int ch, FILE *f)
//{
// ITM_SendChar(ch);
// return ch;
//}
//int fputc(int ch, FILE *f)
//{
// RS485_OUT=1;//485输出
// delay_us(20);
// HAL_UART_Transmit(&huart3, (uint8_t *)&ch, 1, 0xFFFF);
// while(__HAL_UART_GET_FLAG(&huart3,UART_FLAG_TC)!=SET);//等待发送完成
// RS485_OUT=0;//485输入
// return ch;
//}
int fputc(int ch, FILE *f)
{
HAL_UART_Transmit(&huart7, (uint8_t *)&ch, 1, 0xFFFF);
while(__HAL_UART_GET_FLAG(&huart7,UART_FLAG_TC)!=SET);//等待发送完成
return ch;
}
