MSP430F2132 keeps resetting

Robert Lane said:

what are the common reasons for a MSP to reset itself?  

The most common reason is the watchdog. If it is active (and for a failsafe operation, it should) it must be triggered in time. But often in unexpected situations, the code loops longer than the watchdog allows. This is even true for the C initialization itself, when there are large amounts of variables to initialize.

Next is a misconfigured interrupt that is activated but has no ISR to handle it. The CPU then jumps into the void and eventually resets. Especially the TAIE bit is often set in the erroneous assumption that this is necessary to enable the other timer interrupts (especially CCR0).

Other common problems are stack overflows for various reasons: One simply cannot declare more local variavles than the MSP has ram - even though neither compiler nor the linker will throw an error. Also, nested or recursive funcitons or enabling interrupts inside an ISR may cause a stack overflow.

Stack corruption is another reason. If one writes to an arra ywith an index larger than the size of the array, this will write into other memory, including the stack. On next function return, the CPU might 'return' into the field instead of the calling function.

For the same reason, misuse of pointers is also a possible source for resets.

Other possible problems are a missing pullup on the RST pin (unless the MSP is one with internal active pullup, which is in mode devices of 5x/6x family) or a problem with the power supply. Or ESD.