标准crc16,通用javascript,java,c语言

java实现

/**
     *
     * 标准CRC16校验码
     * 
     * @decimalBytes 输入十进制的字节数组
     * @return 返回uint16的数字
     *
     *         demo const {decimalBytes} = GMTools.transToUTF8('123456789'); let
     *         crc = GMTools.crc16(decimalBytes); hexCRC =
     *         GMTools.uint16ToHexString(crc); console.log(hexCRC); // 29b1
     *
     */
    public static int crc16(char[] decimalBytes) {
        int crc = 0xFFFF;
        String[] tabccitt = new String[256];
        int indx = 0;
        for (int i = 0; i < 256; i++) {

            int ccitt = 0;
            int c = i << 8;

            for (int j = 0; j < 8; j++) {

                if (((ccitt ^ c) & 0x8000) > 0) {
                    ccitt = (ccitt << 1) ^ 0x1021;
                } else {
                    ccitt = ccitt << 1;
                }

                c = c << 1;
            }
            tabccitt[indx++] = uint16ToHexString(ccitt);
        }
        for (char c : decimalBytes) {
            int sc = 0x00FF & c;
            int index = (0xFFFF) & ((crc >>> 8) ^ sc);
            int n = Integer.parseInt(tabccitt[index], 16);
            crc = (0xFFFF) & ((0xFFFF) & (crc << 8)) ^ ((0xFFFF) & n);
        }
        return crc;
    }

c 语言实现，stm32都可以用

/**
 * 标准的CRC校验算法
 * @src 校验字符串首地址
 * @sizes 总字节数
 */
unsigned short crc16(const char *src, unsigned long sizes) {
    const char *ptr = NULL;

    unsigned short i, j, n, ccitt;
    unsigned short c = 0;
    unsigned short  tabccitt[256];

    unsigned short crc = 0;
    unsigned short tmp = 0;
    unsigned short sc = 0;

    for (i = 0; i < 256; i++) {
        ccitt = 0;
        c  = i << 8;

        for (j = 0; j < 8; j++) {
            if ( (ccitt ^ c) & 0x8000 ){
                ccitt = ( ccitt << 1 ) ^ 0x1021;
            }
            else{
                ccitt =   ccitt << 1;
            }
            c = c << 1;
        }
        tabccitt[i] = ccitt;
    }

    ptr = src;
    crc = 0xFFFF;
    if (ptr != NULL) for (n = 0; n < sizes; n++) {
        sc = 0X00FF & (unsigned short) *ptr;
        tmp     = (crc >> 8) ^ sc;
        crc     = (crc << 8) ^ tabccitt[tmp];
        ptr++;
    }

    return crc;
}

js 实现

    /**
     *
     * 标准CRC16校验码
     * @decimalBytes 输入十进制的字节数组
     * @return  返回uint16的数字
     *
     * demo
     *    const {decimalBytes} = PMQTPTools.transToUTF8('123456789');
     *      let crc = PMQTPTools.crc16(decimalBytes);
     *      hexCRC = PMQTPTools.uint16ToHexString(crc);
     *      console.log(hexCRC); // 29b1
     *
     */
     static crc16(decimalBytes) {
            let crc = 0xFFFF;

            let tabccitt = [];
            for (let i = 0; i < 256; i++) {

                    let ccitt = 0;
                    let c  = i << 8;

                    for (let j = 0; j < 8; j++) {

                            if ((ccitt ^ c) & 0x8000){
                                    ccitt = (ccitt << 1) ^ 0x1021;
                            }
                            else{
                                    ccitt =  ccitt << 1;
                            }

                            c = c << 1;
                    }

                    tabccitt.push(this.uint16ToHexString(ccitt));
            }

            for (let number of decimalBytes) {

                const sc = 0x00FF & number;
                const index = (0xFFFF) & ((crc >>> 8) ^ sc);

                const n = Number.parseInt(tabccitt[index], 16);
                crc = (0xFFFF) & ((0xFFFF) &(crc << 8)) ^ ((0xFFFF) & n);
            }

            return crc;
    }

此校验算法，为标准的1021多项式与0xFFFF得到即：crc-ccitt 算法，且统一由c语言翻译而成，实现跨语言可以此crc算法,经过实际项目亲测稳定可用。网上有很多的crc算法实现，但是却基本跨语言及稳定性不太可取，因此总结实现一套统一的验证算法。