通信领域中计算CRC是一种常用模式，现在使用golang来计算一组数据的校验值
首先给出计算参考 
| 数据组 | CRC-16 | modbus-crc |
|---|---|---|
| 01 02 03 04 | 2BA1 | A12B |
调用CheckSum 示例
m_data := []byte{0x01,0x02,0x03,0x04} //创建Byte切片 checksum := CheckSum(m_data) //调用计算CRC函数 CheckSum fmt.Printf("check sum:%X \n",checksum) 输出结果：
check sum:2BA1
int16buf := new(bytes.Buffer) //构建int16 输出 binary.Write(int16buf,binary.LittleEndian,checksum) //将int16 从小端转换为 byte数组 fmt.Printf("write buf is: %X",int16buf.Bytes())write buf is: A12B
fmt.Printf("output-before:%X \n",m_data) m_data = append(m_data,int16buf.Bytes()...) fmt.Printf("output-after:%X \n",m_data)output-before:01020304
output-after:01020304A12B
完整代码
package main import ( "fmt" "bytes" "encoding/binary" ) var MbTable = []uint16{ 0X0000, 0XC0C1, 0XC181, 0X0140, 0XC301, 0X03C0, 0X0280, 0XC241, 0XC601, 0X06C0, 0X0780, 0XC741, 0X0500, 0XC5C1, 0XC481, 0X0440, 0XCC01, 0X0CC0, 0X0D80, 0XCD41, 0X0F00, 0XCFC1, 0XCE81, 0X0E40, 0X0A00, 0XCAC1, 0XCB81, 0X0B40, 0XC901, 0X09C0, 0X0880, 0XC841, 0XD801, 0X18C0, 0X1980, 0XD941, 0X1B00, 0XDBC1, 0XDA81, 0X1A40, 0X1E00, 0XDEC1, 0XDF81, 0X1F40, 0XDD01, 0X1DC0, 0X1C80, 0XDC41, 0X1400, 0XD4C1, 0XD581, 0X1540, 0XD701, 0X17C0, 0X1680, 0XD641, 0XD201, 0X12C0, 0X1380, 0XD341, 0X1100, 0XD1C1, 0XD081, 0X1040, 0XF001, 0X30C0, 0X3180, 0XF141, 0X3300, 0XF3C1, 0XF281, 0X3240, 0X3600, 0XF6C1, 0XF781, 0X3740, 0XF501, 0X35C0, 0X3480, 0XF441, 0X3C00, 0XFCC1, 0XFD81, 0X3D40, 0XFF01, 0X3FC0, 0X3E80, 0XFE41, 0XFA01, 0X3AC0, 0X3B80, 0XFB41, 0X3900, 0XF9C1, 0XF881, 0X3840, 0X2800, 0XE8C1, 0XE981, 0X2940, 0XEB01, 0X2BC0, 0X2A80, 0XEA41, 0XEE01, 0X2EC0, 0X2F80, 0XEF41, 0X2D00, 0XEDC1, 0XEC81, 0X2C40, 0XE401, 0X24C0, 0X2580, 0XE541, 0X2700, 0XE7C1, 0XE681, 0X2640, 0X2200, 0XE2C1, 0XE381, 0X2340, 0XE101, 0X21C0, 0X2080, 0XE041, 0XA001, 0X60C0, 0X6180, 0XA141, 0X6300, 0XA3C1, 0XA281, 0X6240, 0X6600, 0XA6C1, 0XA781, 0X6740, 0XA501, 0X65C0, 0X6480, 0XA441, 0X6C00, 0XACC1, 0XAD81, 0X6D40, 0XAF01, 0X6FC0, 0X6E80, 0XAE41, 0XAA01, 0X6AC0, 0X6B80, 0XAB41, 0X6900, 0XA9C1, 0XA881, 0X6840, 0X7800, 0XB8C1, 0XB981, 0X7940, 0XBB01, 0X7BC0, 0X7A80, 0XBA41, 0XBE01, 0X7EC0, 0X7F80, 0XBF41, 0X7D00, 0XBDC1, 0XBC81, 0X7C40, 0XB401, 0X74C0, 0X7580, 0XB541, 0X7700, 0XB7C1, 0XB681, 0X7640, 0X7200, 0XB2C1, 0XB381, 0X7340, 0XB101, 0X71C0, 0X7080, 0XB041, 0X5000, 0X90C1, 0X9181, 0X5140, 0X9301, 0X53C0, 0X5280, 0X9241, 0X9601, 0X56C0, 0X5780, 0X9741, 0X5500, 0X95C1, 0X9481, 0X5440, 0X9C01, 0X5CC0, 0X5D80, 0X9D41, 0X5F00, 0X9FC1, 0X9E81, 0X5E40, 0X5A00, 0X9AC1, 0X9B81, 0X5B40, 0X9901, 0X59C0, 0X5880, 0X9841, 0X8801, 0X48C0, 0X4980, 0X8941, 0X4B00, 0X8BC1, 0X8A81, 0X4A40, 0X4E00, 0X8EC1, 0X8F81, 0X4F40, 0X8D01, 0X4DC0, 0X4C80, 0X8C41, 0X4400, 0X84C1, 0X8581, 0X4540, 0X8701, 0X47C0, 0X4680, 0X8641, 0X8201, 0X42C0, 0X4380, 0X8341, 0X4100, 0X81C1, 0X8081, 0X4040} func CheckSum(data []byte) uint16 { var crc16 uint16 crc16 = 0xffff for _, v := range data { n := uint8(uint16(v)^crc16) crc16 >>= 8 crc16 ^= MbTable[n] } return crc16 } func main(){ //fmt.Printf("lanuch") m_data := []byte{0x01,0x02,0x03,0x04} checksum := CheckSum(m_data) fmt.Printf("check sum:%X \n",checksum) int16buf := new(bytes.Buffer) binary.Write(int16buf,binary.LittleEndian,checksum) fmt.Printf("write buf is: %+X \n",int16buf.Bytes()) fmt.Printf("output-before:%X \n",m_data) m_data = append(m_data,int16buf.Bytes()...) fmt.Printf("output-after:%X \n",m_data) } 完整输出：
check sum:2BA1
write buf is: A12B
output-before:01020304
output-after :01020304A12B
github地址
https://github.com/elegantm/ElegantBlog/blob/master/crc-16-demo
参考：
在线计算CRC
http://www.ip33.com/crc.html