I was doing some simple signal acquisition models in Simulink (Matlab ver. R2017b) with Arduino Due board. I was giving a unipolar square wave (250 Hz) from a function generator to pin 8 of the Arduino Due microcontroller. The 'digital input' block in Simulink is used and the output of the block is connected to a scope. In the 'digital input' block, the sample time is set as 0.001.
Now, when I'm observing the signal, in the scope, it is not at all replicating the input. On the other hand, when I ran the exact same code in Arduino Uno, with the same square wave, the scope is showing the proper output. I've attached couple of pictures of scope outputs, which demonstrate the two scenarios.
Can anybody tell, what can be reason of this mismatch?
Looking forward to some solution of this problem.