stm32 exti, tim to know raising or falling trigger

[ctc.ctc]

Posted on January 20, 2017 at 06:13

I'm learning using stm32 exti, and tim,

there are raising trigger, falling trigger, 'raising or falling trigger'

If I setting  

'raising or falling trigger',

and in trigger time, how can I get the info of the trigger is raising or is falling?

#tim #exti #stm32 #trigger

[S.Ma]

Posted on January 20, 2017 at 08:59

If using an interrupt and the interrupt is faster than the incoming toggling frequency, just read the pin level.

Another way would be to say chose falling edge, and in the interrupt choose rising edge.

Alternate way with timestamp would be to use 2 timer channels one for rising and one for falling edge with DMA buffer option.