STM32中串口中断接收异常

Posted 2023-04-05

我在中断处理函数中用了两种方式处理接收的数据，思路代码基本一样，结果却不一样？
下面是简化的代码：
方法一
void USART1_IRQHandler(void)


if(USART_GetITStatus(USART1, USART_IT_RXNE)!= RESET)

switch(RecState)
case HEAD1:
if(0x68 == USART_ReceiveData(USART1))

RecState = DLTADDR0;

break;
case DLTADDR0:
if(0xaa == USART_ReceiveData(USART1))
RecState = DLTHEAD;

else
RecState = HEAD1;

break;
case DLTHEAD:
if(0x68 == USART_ReceiveData(USART1))
RecState = DLTCS;

else
RecData = HEAD1;

break;
case DLTCS:
if(0xdf == USART_ReceiveData(USART1))
RecState = DLTEND;

else
RecState = HEAD1;

break;
case DLTEND:
if(0x16 == USART_ReceiveData(USART1))
g_DltRec = 1;
RecState = HEAD1;
else
RecState = HEAD1;

break;

default:
RecState = HEAD1;
break;


/*Clear the USART1 Receive interrupt */
USART_ClearITPendingBit(USART1, USART_IT_RXNE);



方法二
void USART1_IRQHandler(void)

if(USART_GetITStatus(USART1, USART_IT_RXNE) !=RESET)

RecData = USART_ReceiveData(USART1);
switch(RecState)
case HEAD1:
if(0x68 == RecData)
RecState = DLTADDR0;

break;
case DLTADDR0:
if(0xaa == RecData)
RecState = DLTHEAD;

else
RecState = HEAD1;

break;
caseDLTHEAD:
if(0x68 == RecData)
RecState = DLTCS;

else
RecData = HEAD1;

break;
case DLTCS:
if(0xdf == RecData)
RecState = DLTEND;

else
RecState = HEAD1;

break;
case DLTEND:
if(0x16 == RecData)
g_DltRec = 1;
RecState = HEAD1;
else
RecState = HEAD1;

break;

default:
RecState = HEAD1;
break;


/*Clear the USART1 Receive interrupt */
USART_ClearITPendingBit(USART1, USART_IT_RXNE);



其实就是加了一个中间变量接收串口的数据，结果却不一样，加了就正确。求解？RecData= USART_ReceiveData(USART1);
发送数据为16进制 68 aa 68 df 16
结果是为了置位g_ DltRec。
RecState为全局变量，默认值是常量HEAD1

参考技术A 我觉得你可以试试把
RecData = USART_ReceiveData(USART1);

也放到每个case中看看是不是对的。如果对的说明不能采用这种模式接受，如果出现同样情况那可能和你case有关了。追问

把RecData = USART_ReceiveData(USART1); 放在每个case中可以。但是不明白为什么if(0x16 == USART_ReceiveData(USART1))不能接收数据，USART_ReceiveData(USART1)不也是读取串口数据吗

STM32串口中断接收问题

void USART6_IRQHandler(void)

while(USART_GetITStatus(USART6, USART_IT_RXNE)!= RESET)

// USART_ClearITPendingBit(USART2, USART_IT_RXNE);
Buffer[dataLen1]=USART6->DR;
dataLen1++;
if(dataLen1>1200)

dataLen1=0;


GPIO_SetBits(GPIOD, GPIO_Pin_13);
Flag=1;

void USART6_Puts(char * str)

while(*str)

USART_SendData(USART6, *str++);
/* Loop until the end of transmission */
while (USART_GetFlagStatus(USART6, USART_FLAG_TC) == RESET); /



main()

GPIO_Config();
USART6_Config();
USART1_Config();
DMA_Config();
NVIC_Config();
GPIO_SetBits(GPIOD, GPIO_Pin_12); //打开LED
while (1)
if(Flag==1)

USART6_Puts(Buffer);
Flag=0;
GPIO_ResetBits(GPIOD, GPIO_Pin_13);



若串口发送的数据在3个以内，接收正常，显示正常，若串口发送数据大于4个的时候，只能接收前四位！小弟望得到大神们的帮助

USART_ClearITPendingBit(USART2, USART_IT_RXNE);这句应该要加进去的，但是看你用的好像是串口6，感觉32有串口6吗？不管怎样，清的中断标志要与用的一样。 参考技术A 你用断点调试看看你进了几次中断，然后单步调试查找问题。