串口多字节接收

1 /* 数据发送格式：

2 * 0 1 2 3 4 ... DataLenth-1 DataLenth

3 * HEAD1 - HEAD2 - DataLenth(n+1) - data_1 - data_2 - ... - data_n - CheckSum

4 * CheckSum = HEAD1 + HEAD2 + DataLenth + data_1 + data_2 + ... + data_n

5 */

6

7 #define FRAME_HEADER1 0xFA // 定义帧头 1

8 #define FRAME_HEADER2 0xFA // 定义帧头 2

9 unsigned char ReceiveDataBuffer[16] = {FRAME_HEADER1, FRAME_HEADER2, 0x00};

10 unsigned char DataBufferCnt = 0x02;

11 unsigned char CheckSum = FRAME_HEADER1 + FRAME_HEADER2;

12 // 串口接收中断程序

13 void USART_IRQHandler(void)

14 {

15 static unsigned char headBufCnt = 0x00;

16 unsigned char buf;

17

18 buf = ReadRegisterReceiveBuffer(); // 读接收寄存器数据到缓冲区

19

20 #if (FRAME_HEADER1 != FRAME_HEADER2) // 检测帧头，两字节帧头不同

21 if(FRAME_HEADER1 == buf) { headBufCnt = 0x01;}

22 else if(0x00 != headBufCnt)

23 {

24 headBufCnt = 0x00;

25 if(FRAME_HEADER2 == buf)

26 {

27 DataBufferCnt = 0x02;

28 CheckSum = FRAME_HEADER1 + FRAME_HEADER2;

29 return;

30 }

31 }

32 #else // 检测帧头，两字节帧头相同

33 if(FRAME_HEADER1 == buf) { headBufCnt ++;}

34 else if(headBufCnt >= 2)

35 {

36 headBufCnt = 0x00;

37 DataBufferCnt = 0x02;

38 CheckSum = FRAME_HEADER1 + FRAME_HEADER2;

39 }

40 else { headBufCnt = 0x00;}

41 #endif /* FRAME_HEADER1 != FRAME_HEADER2 */

42

43 ReceiveDataBuffer[DataBufferCnt] = buf;

44 if((DataBufferCnt-2) < ReceiveDataBuffer[2])

45 {

46 CheckSum += ReceiveDataBuffer[DataBufferCnt]; // 计算校验和

47 DataBufferCnt ++;

48 }

49 else // 数据接收完毕

50 {

51 if(CheckSum == ReceiveDataBuffer[DataBufferCnt]) // 数据校验成功

52 {

53 // 数据校验完毕且正确

54 }

55 DataBufferCnt = 0x02;

56 }

57 }