Error in 'test2/Buffer': All sample times must be discrete. No continuous or constant sample times are allowed.

Hello,

I want to simulate an ADC in simulink using NRZ S/H. this is my first time that I want to use DSP toolbox in simulink. Here is my schematic:

but this error pops up:

Error in 'test2/Buffer': All sample times must be discrete. No continuous or constant sample times are allowed.

I think every thing is discrete.

please let me know your idea for solving this problem.

thank you

[moh mor]

please help me.

[Mathieu NOE]

hello

make sure your solver options specifies that you have fixed sampling rate, which is not simulink options by default