Hi everybody,
I have to design a model for an ADC two step converter using a block that behaves like the non-linear function of the residue (as on page 5 of http://www.eecs.umich.edu/~mpflynn/teaching/design_contest/winter_2004/presentat... ) in Simulink.

I'm a newbie of Simulink, so I figured to use the block "MATLAB fcn" to define the saw toothed function: in a matlab file .m I can describe the behaviour of the block. For example, if u is the input and out is the output, if I write out=cos(u) at the output I will see the cosine of the input u.
So I simply tried this: I use a ramp, a MATLAB fcn with the function out=cos(u) and then I look at the output with a scope, but what I see is the picture attached. Maybe it's a stupid question but....why?  :(  I should see a cosine...
Thank you very much!

Nicola