Exti Block Diagram; Wakeup Event Management; Functional Description; Figure 29. External Interrupt/Event Controller Block Diagram - ST STM32F410 Reference Manual

RM0401
9.2.2

EXTI block diagram

Figure 29
9.2.3

Wakeup event management

The STM32F4xx are able to handle external or internal events in order to wake up the core
(WFE). The wakeup event can be generated either by:
•
enabling an interrupt in the peripheral control register but not in the NVIC, and enabling
the SEVONPEND bit in the Cortex
MCU resumes from WFE, the peripheral interrupt pending bit and the peripheral NVIC
IRQ channel pending bit (in the NVIC interrupt clear pending register) have to be
cleared.
•
or configuring an external or internal EXTI line in event mode. When the CPU resumes
from WFE, it is not necessary to clear the peripheral interrupt pending bit or the NVIC
IRQ channel pending bit as the pending bit corresponding to the event line is not set.
To use an external line as a wakeup event, refer to
9.2.4

Functional description

To generate the interrupt, the interrupt line should be configured and enabled. This is done
by programming the two trigger registers with the desired edge detection and by enabling
the interrupt request by writing a '1' to the corresponding bit in the interrupt mask register.
When the selected edge occurs on the external interrupt line, an interrupt request is
shows the block diagram.

Figure 29. External interrupt/event controller block diagram

®
-M4 with FPU System Control register. When the
Section 9.2.4: Functional
RM0401 Rev 3
Interrupts and events
description.
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