mycrc.m

cyclic redudndancy check program in mat lab

function x=mycrc(data,divisor,type)
if ((type==1)||(type==2))
    n=length(divisor)
    appender=[0 0 0 0]
    dividend=[data]
    if ((type==1))
        dividend=[data,appender]
    end
    dividendA=dividend(1:5)
    dividendB=dividend(6:length(dividend))
    result=dividendA
    while((n-1)~=length(result))
        result=bitxor(result,divisor)
        while(result(1)==0 && ((n-1)~=length(result)))
            result=result(2:length(result))
            if ((length(result)<length(divisor)) && (length(dividendB)~=0))
                result=[result,dividendB(1)]
                dividendB=dividendB(2:length(dividendB))
            end
        end
    end

    x=result

    if (type==2 & result==zeros(size(result)))
        x=[1];
        disp('check successful,data uncorrupted')
    elseif (type==2)
        x=[0]
        disp('check failed data is corrupted')
    end

else
    disp('invalid type entered in 3rd parameter it should either be 1 or 2')
end