STM32的RS232协议示例程序?
时间: 2023-07-30 11:05:21 浏览: 53
以下是一个使用STM32的USART1模块实现RS232协议的示例程序,该程序通过USART1发送和接收数据:
```c
#include "stm32f10x.h"
void USART1_Init(void);
void USART1_SendChar(char ch);
void USART1_SendString(char* str);
char USART1_ReceiveChar(void);
int main(void)
{
USART1_Init();
while(1)
{
char receivedChar = USART1_ReceiveChar();
if(receivedChar != '\0') //如果接收到了有效数据
{
USART1_SendChar(receivedChar); //回传该数据
}
}
}
void USART1_Init(void)
{
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_USART1, ENABLE); //开启GPIOA和USART1的时钟
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9; //USART1_TX
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; //USART1_RX
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOA, &GPIO_InitStructure);
USART_InitTypeDef USART_InitStructure;
USART_InitStructure.USART_BaudRate = 9600;
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_Tx | USART_Mode_Rx;
USART_Init(USART1, &USART_InitStructure);
USART_Cmd(USART1, ENABLE);
}
void USART1_SendChar(char ch)
{
while(USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET); //等待发送缓冲区为空
USART_SendData(USART1, (uint16_t)ch); //发送数据
}
void USART1_SendString(char* str)
{
while(*str)
{
USART1_SendChar(*str++);
}
}
char USART1_ReceiveChar(void)
{
if(USART_GetFlagStatus(USART1, USART_FLAG_RXNE) != RESET) //如果接收缓冲区非空
{
char receivedChar = USART_ReceiveData(USART1); //读取接收到的数据
return receivedChar;
}
else
{
return '\0'; //返回空字符表示没有接收到有效数据
}
}
```
在这个示例程序中,我们使用USART1模块来实现RS232通信。在USART1模块初始化时,我们设置了它的波特率为9600,数据位为8位,停止位为1位,无校验位。在while循环中,我们使用USART1_ReceiveChar函数从USART1接收数据,如果接收到了有效数据,我们就使用USART1_SendChar函数将其回传。