In simulink, what is the maximal sampling frequency of the analog inputs ?

hello I tried to acquire an analog signal (sinusoidal shape with a frequency of 50Hz) using MATLAB/SIMULINK and an analog input pin of ARDUINO MEGA 2560. The model was run in external mode. However, the visualised signal does not match the original signal; it has a discontinuous shape Is that due to the sampling frequency of the analog input ? I use a sampling frequency of 0.0001 seconds attached is the program that I have used Thank you for your help Best regards