我写了个串口3接收，串口2发送的api，为什么没有数据

发布于 2018-06-19 18:04:19 浏览：3162 订阅该版

```#include "usart13.h"	
#include "usart.h"
#include "stm32f4xx.h"
#include "board.h"

#include <rtdevice.h>

void my_usart_init()
{
        //GPIO端口设置
        GPIO_InitTypeDef GPIO_InitStructure;
	USART_InitTypeDef USART_InitStructure;
	NVIC_InitTypeDef NVIC_InitStructure;
	
	RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA,ENABLE); //使能GPIOA时钟
	RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB,ENABLE); //使能GPIOB时钟
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3,ENABLE);//使能USART3时钟接收数据
        RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2,ENABLE);//使能USART2时钟接收数据
	
	//串口3对应引脚复用映射
	GPIO_PinAFConfig(GPIOB,GPIO_PinSource10,GPIO_AF_USART3); //GPIOB10复用为USART3_TXD
	GPIO_PinAFConfig(GPIOB,GPIO_PinSource11,GPIO_AF_USART3); //GPIOB11复用为USART3_RXD

//串口2对应引脚服用映射
	GPIO_PinAFConfig(GPIOA,GPIO_PinSource2,GPIO_AF_USART2); //GPIOA2复用为USART1_TXD
	GPIO_PinAFConfig(GPIOA,GPIO_PinSource3,GPIO_AF_USART2); //GPIOA3复用为USART1_RXD

//USART3端口配置
        GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10| GPIO_Pin_11; //GPIOB10与GPIOB11
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;//复用功能
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;	//速度50MHz
	GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; //推挽复用输出
	GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP; //上拉
	GPIO_Init(GPIOB,&GPIO_InitStructure); //初始化PB10,PB11

//USART2端口配置
        GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2 | GPIO_Pin_3; //GPIOA2与GPIOA3
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;//复用功能
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;	//速度50MHz
	GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; //推挽复用输出
	GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP; //上拉
	GPIO_Init(GPIOA,&GPIO_InitStructure); //初始化PA2，PA3

//USART3（接收） 初始化设置
	USART_InitStructure.USART_BaudRate = 9600;//波特率设置
	USART_InitStructure.USART_WordLength = USART_WordLength_8b;//字长为8位数据格式
	USART_InitStructure.USART_StopBits = USART_StopBits_1;//一个停止位
	USART_InitStructure.USART_Parity = USART_Parity_No;//无奇偶校验位
	USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//无硬件数据流控制
	USART_InitStructure.USART_Mode = USART_Mode_Rx;	//接受模式
        USART_Init(USART3, &USART_InitStructure); //初始化串口3
	
        USART_Cmd(USART3, ENABLE);  //使能串口3
	 
        //USART2 初始化设置
	USART_InitStructure.USART_BaudRate = 115200;//波特率设置
	USART_InitStructure.USART_WordLength = USART_WordLength_8b;//字长为8位数据格式
	USART_InitStructure.USART_StopBits = USART_StopBits_1;//一个停止位
	USART_InitStructure.USART_Parity = USART_Parity_No;//无奇偶校验位
	USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//无硬件数据流控制
	USART_InitStructure.USART_Mode = USART_Mode_Tx;	//发送模式
        USART_Init(USART2, &USART_InitStructure); //初始化串口2
	
        USART_Cmd(USART2, ENABLE);  //使能串口2
 
	USART_ITConfig(USART3, USART_IT_RXNE, ENABLE);//开启相关中断

//USART3 NVIC 配置
        NVIC_InitStructure.NVIC_IRQChannel = USART3_IRQn;//串口3中断通道
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=3;//抢占优先级3
	NVIC_InitStructure.NVIC_IRQChannelSubPriority =3;		//子优先级3
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;			//IRQ通道使能
	NVIC_Init(&NVIC_InitStructure);	//根据指定的参数初始化VIC寄存器、

}

//串口3中断服务程序
void USART3_IRQHandler(void)                	
{
	u8 Res;
	if(USART_GetITStatus(USART3, USART_IT_RXNE) != RESET)  //接收中断(接收到的数据必须是0x0d 0x0a结尾)
	{
		Res =USART_ReceiveData(USART3);//(USART3->DR);	//读取接收到的数据
                USART_SendData(USART2,Res);		 
        } 
}

void usart2_send(void)
{ 
	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);//设置系统中断优先级分组2 
	my_usart_init();	//串口初始化波特率为9600 
	while(1);
}

#ifdef RT_USING_FINSH
#include <finsh.h>
/* 串口收发api */
FINSH_FUNCTION_EXPORT(usart2_send, startup usart1 send);
#endif
```