
Extended interrupts and event controller (EXTI)
RM0453
RM0453 Rev 2
The masking block provides the event input distribution to the different wakeup, interrupt
and event outputs, and the masking of these.
Figure 54. EXTI block diagram
MSv60758V1
EVG
EVG
EXTI
Pulse
Direct event(x) or
configurable event(y)
it_exti_per(y)
(1)
c1_event
c2_evt_exti
c2_wakeup
AHB interface
PWR
CPU1
CPU2
rxev
nvic(x)
rxev
nvic(x)
Peripheral
sys_wakeup
nvic(y)
nvic(y)
Wakeup
Interrupt
Direct event(x)
Pulse
c1_evt_exti
c2_event
c1_evt_rst
c2_evt_rst
hclk
c2_fclk
c1_fclk
c1_wakeup
1) it_exti_per(y) only available for configurable events (y)
Registers
Masking
Event
trigger
Events
Table 91. EXTI pin overview
Pin name
I/O
Description
AHB interface
I/O
EXTI register bus interface
hclk
I
AHB bus clock and EXTI system clock
Configurable
event(y)
I
Asynchronous wakeup events from peripherals which do not have an associated interrupt
and flag in the peripheral
Direct event(x)
I
Synchronous and asynchronous wakeup events from peripherals which have an
associated interrupt and flag in the peripheral
it_exti_per (y)
O
Interrupts to the CPU associated with the configurable event (y)
cn_evt_exti
O
High-level sensitive event output for the CPUn, synchronous to hclk
cn_evt_rst
I
Asynchronous reset input to clear cn_evt_exti
sys_wakeup
O
Asynchronous system wakeup request to PWR for ck_sys and hclk
cn_wakeup
O
Wakeup request to PWR for the CPUn, synchronous to hclk
Table 92. EVG pin overview
Pin name
I/O
Description
cn_fclk
I
CPUn free running clock
cn_evt_in
I
High-level sensitive events input from EXTI, asynchronous to the CPUn clock
cn_event
O
Event pulse, synchronous to the CPUn clock
cn_evt_rst
O
Event reset signal, synchronous to the CPUn clock