Background: I am trying to make my embedded application go to sleep when there is no CAN activity with the __WFI() and then wake up whenever a CAN interrupt is received. Before enterring sleep mode, I disable all interrupts and clear their pending states in the NVIC registers.
To start, right now I'm just trying to make sure that I can sleep forever when I have all interrupts disabled.
for(int i = 0; i < IRQ_MAX; i++)
I checked the NVIC registers, and they are all set to 0, which should mean that all interrupts are disabled and there are no pending interrupts. However, everytime I execture the WFI (Wait for interrupt) instruction, it will just NOP on me.
Why can I not enter sleep mode? Do I actually have to somehow disable all of my peripherals and disable the interrupts at their source or is there a way to just mask all interrupts minus the CAN?
I have tried this with the debugger both connected and disconnected.
Thank you for your time. Let me know if there is anything I can do to clarify the question.