TI 2000 BiSS-C Absolute Encoder external mode mex-file error in simulink

Hi,

In my university project, I am triying to read position from absolute encoder with F28379D launchpad in Simulink.

I found great example what exactly I wanted.

https://ch.mathworks.com/matlabcentral/fileexchange/92788-simulink-reference-application-examples-for-ti-c2000?s_tid=answers_rc2-1_p4_MLT.

So far, everything is fine. However, when I ran F2837x_CPU2_bissc.slx in external mode, I got error"Error occured while executing External Mode Mex-File 'ext-comm' .

I could not find how to solve the errror. Can you help me to fix this error?

Best regards.

[mes]

So far,I have tried to run the code many times. Interestingly, 2 times the code was worked properly and positon value could be read. In all other attempts, I got same error.

How can i eliminate this error?