STM32 serial port interrupt receiving data

The data frame meets the following format: 

void USART6_Init (void)

{

GPIO_InitTypeDef GPIO_InitStructure;

USART_InitTypeDef USART_InitStructure;

NVIC_InitTypeDef NVIC_InitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART6,ENABLE);

RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC,ENABLE); //Modify

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6|GPIO_Pin_7;//Modify

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;

GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;

GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;

GPIO_InitStructure.GPIO_Speed ​​= GPIO_Speed_50MHz;

GPIO_Init(GPIOC,&GPIO_InitStructure);//Modify

GPIO_PinAFConfig(GPIOC,GPIO_PinSource6,GPIO_AF_USART6);//Modify

GPIO_PinAFConfig(GPIOC,GPIO_PinSource7,GPIO_AF_USART6); //Modify

NVIC_InitStructure.NVIC_IRQChannel = USART6_IRQn;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);

USART_InitStructure.USART_BaudRate = 115200;

USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;

USART_InitStructure.USART_Mode = USART_Mode_Tx|USART_Mode_Rx;

USART_InitStructure.USART_Parity = USART_Parity_No;

USART_InitStructure.USART_StopBits = USART_StopBits_1;

USART_InitStructure.USART_WordLength = USART_WordLength_8b;

USART_Init(USART6,&USART_InitStructure);

USART_ITConfig(USART6,USART_IT_RXNE,ENABLE);//Enable receive interrupt

USART_Cmd(USART6,ENABLE);

}

void USART6_IRQHandler()

{

unsigned char rCh;

static char rCnt = 0;

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

{

rCh = USART_ReceiveData(USART6);

COM6_RecvBuf[rCnt] = rCh;

if (rCnt == 0) //frame header 0xAA

{

rCnt = (0xAA != rCh)?0:rCnt+1;

}

else if (rCnt == 1) //frame header 0x55

{

rCnt = (0x55 != rCh)?0:rCnt+1;

}

else if (rCnt == 2) //type type

{

//Here you can process the above according to the type range

rCnt++;

}

else if (rCnt == 3) //length len

{

rCnt++;

}

else if (rCnt > 3) //value

{

rCnt++;

if (rCnt == 6+COM6_RecvBuf[3])

{

rCnt = 0;

memcpy(COM6_RecvBufBck,COM6_RecvBuf,RECV_BUF_SZ);//buffer

COM6_RecvFin = 1; //Notify the main loop processing

}

}

}

}

int main(void)

{

int i;

// Code segment 1

while (1) //The loop cannot be too slow, otherwise the data buffer will be partially modified

{

// Code segment 2

if (COM6_RecvFin == 1)

{

COM6_RecvFin = 0;

CMD_Analysis(); //Analyze the received frame data

}

// Code segment 3

}

return 0;

}