常用代码

• 异或运算加密

/**加密算法**/
private static short encryption(short msgId, short mesType) {
    short y;
    short desCode;
    y = (short) ((msgId % 10 * 10 + msgId % 100 / 10 + mesType * 2) % 100);
    System.out.println("y:" + y);
    desCode = (short) BLE_Cipher[y];
    return desCode;
}

• CRC8校验

/**
 * CRC8校验码
 * @param buffer
 * @param key
 * @return
 */
public static byte getCRCR8(byte[] buffer, short key) {
    short i;
    byte crc;
    crc = 0;
    int ptr = 0;
    int len;
    len = buffer.length;
    while (len-- != 0) {
        for (i = 0x80; i != 0; i >>= 1) {
            if ((crc & 0x80) != 0) {
                crc <<= 1;
                crc ^= key;
            } else {
                crc <<= 1;
            }
            if ((buffer[ptr] & i) != 0) {
                crc ^= key; /* 校验模数 */
            }
        }
        ptr++;
    }
    return crc;
}