[quote user="Robbie Valentine"]It looks like there are some assembly instructions at 0x00000 but I don't know why.[/quote]That is a sign that the processor has "crashed" and set the program counter to the invalid value of zero.
[quote user="Robbie Valentine"]I'm running at ~20Mhz[/quote]According to Figure 2. Frequency vs Supply Voltage in the MSP430F5637 datasheet to run at 20MHz you need to have:
- A Supply Voltage in the range 2.4V to 3.6V
- PMMCOREVx set to 3
Failure to meet these conditions can lead to intermittent crashes.
Also, if you are using a custom hardware design check that there is the recommended 470nF capacitor on VCORE, as failure to do that can also cause intermittent operation.
Assuming the Supply Voltage, PMMCOREVx setting, VCORE capacitor are OK there might be a software cause such as either:
- A stack overflow
- An unhandled interrupt (meaning an interrupt is generated for which there is no handler)