How to convert any continuous signal to its discrete form in Simulink?

Hello,

I have to convert any sinusoidal continuous signal let say x(t)=230 Cos (100πt+π/4) at frequency 50Hz into its discrete form. I have attached the model also. But not getting correct waveform. pulse generator has been used here that generates 1000 pulses for sampling rate of 20 samples/cycle in 1 second as an input signal and has been sampled in accordance with output of the pulse generator. The quantizer is used to round off error and discretize the input at the interval of 0.5sec.