用C语言写STM32单片机串口通信的代码

以下是一个简单的用C语言编写的STM32单片机串口通信代码示例：

#include "stm32f10x.h"

void USART1_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1 | RCC_APB2Periph_GPIOA, ENABLE);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOA, &GPIO_InitStructure);

USART_InitStructure.USART_BaudRate = 115200;
USART_InitStructure.USART_WordLength = USART_WordLength_8b;
USART_InitStructure.USART_StopBits = USART_StopBits_1;
USART_InitStructure.USART_Parity = USART_Parity_No;
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
USART_Init(USART1, &USART_InitStructure);

USART_Cmd(USART1, ENABLE);
}

void USART1_SendChar(char ch)
{
while (USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
USART_SendData(USART1, (uint16_t)ch);
}

char USART1_ReceiveChar(void)
{
while (USART_GetFlagStatus(USART1, USART_FLAG_RXNE) == RESET);
return (char)USART_ReceiveData(USART1);
}

int main(void)
{
USART1_Init();

while (1)
{
char ch = USART1_ReceiveChar();
USART1_SendChar(ch);
}
}

注意：以上代码仅供参考，具体实现可能需要根据具体的硬件和需求进行修改。