What is the maximum input capture frequency in STM32F7?

[choies1]

Posted on March 27, 2018 at 00:23

I am using STM32F7(216MHz). When I test input capture of TIM2 and TIM11, rising edge  interrupt was missimg some time. The callback function is not call by interrupt at the ratuo about 1 of 100. Input signal frequency is 450kHz.

What should I do to captue input signal without missing interrupt function call.

Thanks.

#stm32f7 #interrupt #maximum-frequency #input-capture

[T J]

Posted on March 27, 2018 at 01:52

the IO clock is set to slow medium or fast. that is double your maximum frequency.

the pin has to go up and be clocked in, and it has to go down and be clocked in..

your maximum frequency is half the IO pin clock frequency.

[Tesla DeLorean]

Posted on March 27, 2018 at 02:26

At higher frequencies consider

a) Counting pulses over an integration period

b) Use input prescaler to measure the time over 8x periods

c) Use DMA to capture time stamps, and decimate interrupt load by defining buffer length for samples.