STM32F3 pin external interrupt and Alternate Function mode

[tgadeyne]

Posted on December 12, 2017 at 11:28

Hello,

I am using a STM32F334.

Is it possible to configure a pin in Alternate Function Mode (Timer input Channel for my project) and to use at the same time the pin as an external interrupt source ?

It seems to work properly in my project but I am surprised it does and could not find any information on this case in the Reference Manual. Is it unrecommended to do it ?

According to Reference Manual, external interrupts are handled through EXTI and SYSCFG_EXTICRx registers while mode of GPIO pin is handled through GPIOx_MODER registers which are not related.

Thank you,

#pin-configuration

[waclawek.jan]

Posted on December 14, 2017 at 01:49

EXTI works in parallel to all other functionalities of the pin (except perhaps when set to Analog).

This is not a very well documented detail indeed.

JW

[tgadeyne]

Posted on December 14, 2017 at 08:43

Thank you for your answer Jan,

It confirms what I figured out.

Thibault