Hi Nakul,
I understand you would like to disable the external mode in TI C2000. You can try building the code by pressing “Ctrl + B” instead of pressind the play button.
Also, you can try using the “Build” option in the hardware tab of Simulink, find the "Deploy" section and press "Build, Deploy & Start" or "Build".
You can refer to the following answer if you need more help.
