Error 'ext_comm' ExtTargetPktPending() call failed while checking for target pkt? And ExtSetTargetPkt() call failed on CLOSE ?

I'm doing project about Arduino with Matlab Simulink S-function

I create a model: constant block (value =1) ---> S-function block block ---> Digital output (Pin 13);

In model I set Time simulation= 50s, sample time=1s;

S-function block with content: Single input, single output (SISO) with output= input. I have add three function subsystem: 1. multiplyMatrix (A * B matrix), 2. transposeRectMatrix (B= A_T matrix), 3. pinv3 (return A= G* G_T matrix). I attached file S-function: ARX_Gimbal

In mdlOutputs, I called pinv3 function to calculate theta2 variable. And then, I run Simulink at External Mode, the first model run is good, but when timer= 36s, I don't know why my system stopped and received error:

Where, I mex this S-function by matlab 2018a, visual studio 2012 pro. Thanks everyone !!!

[Alfredo M.]

Did you happen to have this issue fixed? I have a similar one when I try to compule a Simulink model into an S-function and then I try to run it in Rapid Accelerator mode.