"CM4 is in lockup" - when does it happen

[dry]

There is a reset or interrupt source called "CM4 is in lockup". But what I cannot find in the Vybrid manual describing when can this happen.

When and why can this happen?

[dry · Accepted solution]

Hi Yuri,

ARM M4 manual says "..The processor enters a lockup state if a fault occurs when executing the NMI or HardFault handlers. "

http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0553a/BGBFCHGC.html 

Thus it shouldn't be in the state just after system reset.