stm32f207 RS485通信问题，只能连续收发一个字节

只看该作者 · 2015-2-16 13:04

大家帮我看看。只能收发一个字节，发多了接收不到，貌似溢出了，如何处理呢？

只看该作者 · 2015-2-16 13:07

程序代码如下：#include "pbdata.h"
//#include "stdio.h"

void RCC_Configuration(void);
void GPIO_Configuration(void);
void NVIC_Configuration(void);
void USART_Configuration(void);
uint32_t uartreceive;

int main(void)
{
RCC_Configuration();    //ÏµÍ³Ê±ÖÓ³õÊ¼»¯
GPIO_Configuration(); //¶Ë¿Ú³õÊ¼»¯
USART_Configuration();//´®¿Ú³õÊ¼»¯
NVIC_Configuration(); //ÖÐ¶Ï³õÊ¼»¯

   GPIO_ResetBits(GPIOD,GPIO_Pin_7);
while(1);
}

void RCC_Configuration(void)
{
SystemInit();
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2,ENABLE);
}

void GPIO_Configuration(void)
{
GPIO_InitTypeDef  GPIO_InitStructure;

GPIO_PinAFConfig(GPIOD, GPIO_PinSource5, GPIO_AF_USART2);
  GPIO_PinAFConfig(GPIOD, GPIO_PinSource6, GPIO_AF_USART2);
GPIO_PinAFConfig(GPIOD, GPIO_PinSource7, GPIO_AF_USART2);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;//TX ¸´ÓÃÍÆÍìÊä³ö
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(GPIOD, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;//RX ¸¡¿ÕÊäÈë
  //GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
  GPIO_Init(GPIOD,&GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin=GPIO_Pin_7;//485_CS ÍÆÍìÊä³ö
GPIO_InitStructure.GPIO_Mode=GPIO_Mode_OUT;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(GPIOD,&GPIO_InitStructure);
}

void NVIC_Configuration(void)
{
NVIC_InitTypeDef NVIC_InitStructure;

NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);

NVIC_InitStructure.NVIC_IRQChannel = USART2_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
}

void USART_Configuration(void)
{
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_Rx | USART_Mode_Tx;

USART_Init(USART2,&USART_InitStructure);

  USART_ITConfig(USART2,USART_IT_RXNE,ENABLE);
USART_Cmd(USART2,ENABLE);
USART_ClearFlag(USART2,USART_FLAG_TC);
}

中断处理如下：
void USART2_IRQHandler(void)
{
   uartreceive = 0;
if(USART_GetITStatus(USART2,USART_IT_RXNE)!=RESET)
{

static int k = 0;
//  uartreceive=USART_ReceiveData(USART2);
uartreceive=USART2->DR;

GPIO_SetBits(GPIOD,GPIO_Pin_7);
delay_ms(1);

//USART_ClearITPendingBit(USART2, USART_IT_RXNE);
//USART_ClearFlag(USART2, USART_FLAG_RXNE);

USART_SendData(USART2,uartreceive);
while(USART_GetFlagStatus(USART2,USART_FLAG_TXE)==RESET);
delay_ms(1);
delay_ms(1);
GPIO_ResetBits(GPIOD,GPIO_Pin_7);
}
}