Hi, I am digging into a bit details of freertos. The compiler i am using is keil. In RVDS source code, all ARM cortex port.c files configures timer via vPortSetupTimerInterrupt() function. And can be replaced/disabled via configOVERRIDEDEFAULTTICK_CONFIGURATION macro. BUT In ARMCM4MPU port.c, none of the above exists. There is no macro check to disable function. Also the function is renamed to prvSetupTimerInterrupt(). Whats the logic behind this??

There is no particular reason for this – just that functionality has not been added to the MPU port. If it is something you need then just edit the code so the same mechanism can be used if you build the MPU version. I think Keil can use weak symbols now too, making the use of configOVERRIDEDEFAULTTICK_CONFIGURATION obsolete.

Thank you Sir for the nice answer. 🙂