% crc16.m
%
%The CRC calculation is based on following generator polynomial:
%G(x) = x16 + x12 + x5 + 1
%
%The register initial value of the implementation is: 0xFFFF
%
%used data = string -> 1 2 3 4 5 6 7 8 9
%
% Online calculator to check the script:
%http://www.lammertbies.nl/comm/info/crc-calculation.html
%
%

function crc = crc16(data)

  % crc look up table

  Crc_ui16LookupTable=[0,4129,8258,12387,16516,20645,24774,28903,33032,37161,41290,45419,49548,...
    53677,57806,61935,4657,528,12915,8786,21173,17044,29431,25302,37689,33560,45947,41818,54205,...
    50076,62463,58334,9314,13379,1056,5121,25830,29895,17572,21637,42346,46411,34088,38153,58862,...
    62927,50604,54669,13907,9842,5649,1584,30423,26358,22165,18100,46939,42874,38681,34616,63455,...
    59390,55197,51132,18628,22757,26758,30887,2112,6241,10242,14371,51660,55789,59790,63919,35144,...
    39273,43274,47403,23285,19156,31415,27286,6769,2640,14899,10770,56317,52188,64447,60318,39801,...
    35672,47931,43802,27814,31879,19684,23749,11298,15363,3168,7233,60846,64911,52716,56781,44330,...
    48395,36200,40265,32407,28342,24277,20212,15891,11826,7761,3696,65439,61374,57309,53244,48923,...
    44858,40793,36728,37256,33193,45514,41451,53516,49453,61774,57711,4224,161,12482,8419,20484,...
    16421,28742,24679,33721,37784,41979,46042,49981,54044,58239,62302,689,4752,8947,13010,16949,...
    21012,25207,29270,46570,42443,38312,34185,62830,58703,54572,50445,13538,9411,5280,1153,29798,...
    25671,21540,17413,42971,47098,34713,38840,59231,63358,50973,55100,9939,14066,1681,5808,26199,...
    30326,17941,22068,55628,51565,63758,59695,39368,35305,47498,43435,22596,18533,30726,26663,6336,...
    2273,14466,10403,52093,56156,60223,64286,35833,39896,43963,48026,19061,23124,27191,31254,2801,6864,...
    10931,14994,64814,60687,56684,52557,48554,44427,40424,36297,31782,27655,23652,19525,15522,11395,...
    7392,3265,61215,65342,53085,57212,44955,49082,36825,40952,28183,32310,20053,24180,11923,16050,3793,7920];

  ui16RetCRC16 = hex2dec('FFFF');
  for I=1:length(data)
    ui8LookupTableIndex = bitxor(data(I),uint8(bitshift(ui16RetCRC16,-8)));
    ui16RetCRC16 = bitxor(Crc_ui16LookupTable(double(ui8LookupTableIndex)+1),mod(bitshift(ui16RetCRC16,8),65536));
  end
  crc=dec2hex(ui16RetCRC16);

endfunction












