Java crc verification and javacrc Verification
<Span style = "color: # ff0000;"> English verification: </span>
/*** Calculate and generate the verification code ** @ param data * The data to be verified * @ return */public static String Make_CRC (byte [] data) {byte [] buf = new byte [data. length]; // store the data for (int I = 0; I <data. length; I ++) {buf [I] = data [I];} int len = buf. length; int crc = 0 xFFFF; for (int pos = 0; pos <len; pos ++) {if (buf [pos] <0) {crc ^ = (int) buf [pos] + 256; // XOR byte into least sig. byte of // crc} else {crc ^ = (int) buf [pos]; // XOR byte into least sig. byte of crc} for (int I = 8; I! = 0; I --) {// Loop over each bitif (crc & 0x0001 )! = 0) {// If the LSB is setcrc> = 1; // Shift right and XOR 0xA001crc ^ = 0xA001 ;} else // Else LSB is not setcrc> = 1; // Just shift right} String c = Integer. toHexString (crc); if (c. length () = 4) {c = c. substring (2, 4) + c. substring (0, 2);} else if (c. length () = 3) {c = "0" + c; c = c. substring (2, 4) + c. substring (0, 2);} else if (c. length () = 2) {c = "0" + c. substring (1, 2) + "0" + c. substring (0, 1);} return c ;}
Verification with Chinese characters:
CRC16Modbus type
Package com. kehui. utils;/*** used to calculate Chinese-contained verification **/public class CRC16Modbus {private static final int [] TABLE = {0x0000, 0xc0c1, 0xc181, 0x0140, 0xc301, 0x03c0, 0x0280, 0xc241, 0xc601, 0x06c0, 0x0780, 0xc741, 0x0500, 0xc5c1, 0xc481, 0x0440, 0xcc01, 0x0cc0, 0x0d80, 0xcd41, primary, 0xcfc1, 0xce81, primary, 0x0a00, 0xcac1, 0xcb81, 0x0b40, 0xc901, 0x09c0, 0x0880, 0xc841, primary, 0x18c0, 0x1980, 0xd941, 0x1b00, 0xdbc1, 0xda81, 0x1e00, 0xdec1, 0xdf81, 0x1f40, 0xdd01, 0x1dc0, 0x1c80, 0xdc41, 0x1400, 0xd581, 0x1540, 0xd701, 0x17c0, 0x1680, 0xd641, 0xd201, 0x12c0, 0x1380, 0xd341, 0x1100, 0xd1c1, 0xd081, 0x1040, 0xf001, 0x30c0, 0x3180, 0xf141, 0x3300, 0xf3c1, values, 0x3240, 0x3600, 0xf6c1, 0xf781, 0x3740, 0xf501, 0x35c0, 0x3480, 0xf441, 0x3c00, 0xfcc0, 0xfd81, 0x3d40, 0xff01, 0x3fc0, 0x3e80, 0xfe41, 0xfa01, 0x3ac0, 0x3b80, 0xfb41, 0x3900, 0xf9c1, 0xf881, 0x3840, 0x2800, 0xe8c1, 0xe981, 0x2940, 0xeb01, expires, 0x2a80, 0xea41, 0xee01, 0x2ec0, 0x2f80, 0xef41, 0x2d00, 0xedc1, 0xec81, 0x2c40, 0xe401, 0x24c0, 0x2580, 0x2700, 0xe7c1, Hangzhou, 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, 0x6e80, 0xae41, 0xaa01, 0x6ac0, 0x6b80, 0xab41, 0x6900, 0xa9c1, 0xa881, 0x6840, 0x7800, 0xb8c1, 0xb981, 0x7940, 0xbb01, primary, primary, 0xba41, 0xbe01, 0x7ec0, 0x7f80, 0xbf41, 0x7d00, 0xbdc1, 0xbc81, 0x7c40, primary, 0x74c0, 0x7580, 0xb541, 0x7700, 0xb7c1, primary, 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, Hangzhou, 0x5b40, 0x9901, 0x59c0, 0x5880, 0x9841, 0x8801, 0x48c0, 0x4980, 0x8941, 0x4b00, 0x8bc1, primary, 0x4a40, 0x4e00, 0x8ec1, primary, 0x4f40, 0x8d01, 0x4dc0, 0x4c80, 0x8c41, 0x4400, 0x84c1, 0x8581, 0x4540,0x8701, 0x47c0, 0x4680, 0x8641, 0x8201, 0x42c0, 0x4380, 0x8341,0x4100, 0x81c1, 0x8081, 0x4040}; private int sum = 0 xFFFF; public long getValue () {return sum;} public void reset () {sum = 0 xFFFF;} public void update (byte [] B, int off, int len) {for (int I = off; I <off + len; I ++) update (int) B [I]);} public void update (int B) {sum = (sum> 8) ^ TABLE [(sum) ^ (B & 0xff) & 0xff];} public byte [] getCrcBytes () {long crc = (int) this. getValue (); byte [] byteStr = new byte [2]; byteStr [0] = (byte) (crc & 0x000000ff); byteStr [1] = (byte) (crc & 0x0000ff00) >>> 8); return byteStr ;}}
Write when using:
/** Data that requires verification code */byte [] c = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};/** calculate the Verification Code */CRC16Modbus crc = new CRC16Modbus (); for (int d: c) {crc. update (d);} byte [] byteStr = new byte [2]; <span style = "color: # ff0000;" >/// <span style = "font-family: arial, Helvetica, sans-serif; "> byteStr is the request </span> byteStr [0] = (byte) (crc. getValue () & 0x000000ff); byteStr [1] = (byte) (crc. getValue () & 0x0000ff00) >>> 8 );