Reading Data from Excel Sheets in an Embedded Matlab function

Hey Guys,

i am trying to read data from Excel sheets from within a matlab function in Simulink. M So far my code is:

 function Leistung_Maschine_1 = function1(s_off,s_de,s_sb,s_op,s_w,time,data)
 coder.extrinsic('assignin')

 if s_off==1
    Leistung_Maschine_1=0;
 elseif s_de == 1
    Leistung_Maschine_1=data(4);
 elseif s_sb == 1
    Leistung_Maschine_1=data(3);
 elseif s_op == 1
    Leistung_Maschine_1=data(2);
 elseif s_w == 1
    Leistung_Maschine_1=data(1);
 else
    disp('warning');
    Leistung_Maschine_1=NaN;

 assignin('base','Leistung_Maschine_1',Leistung_Maschine_1);
end

The problem is that, for example, when input s_op goes from 0 to 1 at simulation time 200, the 200th row of data(2) is given out as output but it should take the first value in row 1 and then starts to read out the values row after row. Also, at any given reentering of a statement at any simulation time, the output should start at the first row.

Does anyone know how i can fix my code?

Thank you very much!!