Purpose of global interrupt (NVIC)

[Renato Valentim]

Hello!

In STM32CubeMX I tried adding a input Compare direct mode to a timer for the STM32F767 part.

It did not work until I checked the option under "NVIC Settings" to make the timer a global interrupt.

Excuse the beginner question, but should not all timer interrupts be global always? I'm not sure I understand the concept of a "local" interrupt and why there is even this NVIC option at all, if the interrupt does not work without it?

Thanks

• Renato

[TDK]

NVIC is part of the Cortex-M7 core, whereas the peripherals are a ST creation.

Generally, it doesn't make sense to enable them in the peripheral but not in the NVIC.

Some NVIC interrupts are shared between multiple peripherals and/or multiple events, so in this case the only logical thing is to allow them to be enabled individually at the local level. Sometimes you want to enable the interrupt for RXNE, but not for TXE, so you need this local-level resolution.

[Nikita91]

So for CubeMX:

global mean: NVIC level

local mean : peripheral level ?