how can I use while loop in MAT-LAB function block within Simulink model

the required algorithm is to execute output signal value = 1 for every output port in sequence with time delay between each execution. the proposed code:

function [s1, s2, s3, s4, s5] = abs(f)

%#codegen

i=1; %iteration start

while f<=49.5

    pause (1) %time delay

    si = 1 %proposed output

end

    i=i+1

end

but it didn't work include error ('Error using whileloopcode (line 4) Not enough input arguments.')