我不能用arduino创建正确的omron hmi crc代码

Question

你好，我正在尝试通过modbus rtu与arduino通信omron hmi。我只是在听arduino的数据，这样我就可以分析数据传输了。但是当我试图创建它的crc时，我无法获得corrrect数据。下面是算法和我编写的代码。如果有人知道这个问题，请帮帮我。

块引用的CRC-16计算示例一次在16位处理寄存器中处理1字节的消息，称为CRC寄存器。1在CRC寄存器中设置FFFF十六进制的默认值。2获取CRC寄存器的内容和消息的第一个字节的异或，并将结果返回CRC寄存器。3 CRC寄存器的内容向右移动1位，0放置在MSB中。4如果从LSB移位的位为0，则重复步骤3(即寄存器的内容被移动1位)。如果从LSB移出的位为1，则对CRC寄存器和A001十六进制的内容进行异或，并将结果返回到CRC寄存器。5重复步骤3和4，直到寄存器的内容向右移动8位。6如果没有到达消息的结尾，则取消息的下一个字节和CRC寄存器的异或，结果返回到CRC寄存器，并且从步骤3.7开始重复该过程，结果( CRC寄存器中的值)放置在消息的较低字节中。如果计算出的CRC值为1234十六进制，则追加结果的示例如下所示。

 crc=0xFFFF;  //A default value of FFFF hex is set in the CRC register.
 LSB=0; 
 cnt=0;
 
  
 Serial.print("CRC-");
 Serial.println(crc,BIN);
 for(i=0;i<13;i++)
 {
                      //An XOR is taken of the contents of the CRC register and the first byte of the message, and the
                      //result is returned to the CRC register.
                      //If the end of the message has not been reached, an XOR is taken of the next byte of the
                      //message and the CRC register, the result is returned to the CRC register, and the procedure is
                      //repeated from step 3.
  crc=crc^data[i]; 
  LSB=crc&1;
  cnt=0;

  while(cnt<8)       //Steps 3 and 4 are repeated until the contents of the register have been shifted 8 bits to the right.
  {

    crc=crc>>1;             //The contents of the CRC register is shifted 1 bit to the right, and 0 is placed in the MSB.
    crc=crc&0x7fff;
    cnt++;
  
    //LSBe=LSB;
    LSB=crc&1;
    if(cnt==8)break;
    Serial.print("LSB-");
 Serial.println(LSB,HEX);
 
// If the bit shifted from the LSB is 0, step 3 is repeated (i.e., the contents of the register is shifted 1 more bit).
//If the bit shifted from the LSB is 1, an XOR is taken of the contents of the CRC register and
//A001 hex, and the result is returned to the CRC register.

    if(LSB==0)
    {
      crc=crc>>1;
      crc=crc&0x7fff;
      cnt++;
       Serial.print("CRC2-");
 Serial.println(crc,BIN);
    }
    else if(LSB==1)
    {
       crc=crc^operation;
     Serial.print("CRC3-");
 Serial.println(crc,BIN);
    }
  }
 }

Answer 1

对于每一个字节的数据：

crc ^= data[i];
crc = crc & 1 ? (crc >> 1) ^ 0xa001;
crc = crc & 1 ? (crc >> 1) ^ 0xa001;
crc = crc & 1 ? (crc >> 1) ^ 0xa001;
crc = crc & 1 ? (crc >> 1) ^ 0xa001;
crc = crc & 1 ? (crc >> 1) ^ 0xa001;
crc = crc & 1 ? (crc >> 1) ^ 0xa001;
crc = crc & 1 ? (crc >> 1) ^ 0xa001;
crc = crc & 1 ? (crc >> 1) ^ 0xa001;

这就是全部。