how to specify additional parameters(vector or matrix) using level2 matlab s-function

here's the level1 s-function,tTime and yStep are both vector parameters:

function [sys,x0,str,ts]= mdlInitializeSizes

if true
sizes = simsizes;
sizes.NumContStates = 0;
sizes.NumDiscStates = 0;
sizes.NumOutputs = 1;
sizes.NumInputs = 0;
sizes.DirFeedthrough = 0;
sizes.NumSampleTimes = 1;
sys = simsizes(sizes);
x0 = [];
str =[];
ts = [0 0];

function sys =mdlOutputs(t,tTime,yStep)

i=find(tTime<=t); sys=yStep(i(end));

the problem is that i don't know how write the level2 output function:

function Outputs(block)

if true
i=find(tTime<=t);
block.OutputPort(1).Data =  yStep(i(end));
end

the tTime and yStep are vectors specified by user,such as tTime=[0.1 0.2 0.3 0.4]; yStep=[-1 1 0 2];