STM32F4 TIM Frequency and Delay Measurement

[roland23]

Posted on November 06, 2015 at 08:35

I have the following Problem:

I have two input signals. The frequency of the signals is equal, but there is a delay between this signals.

I have to measure the delay between the rising edge of the first input and the rising edge of the second input. I have also to measure the frequency of one Signal.

I'm using the STM32F429.

Example:

Is it possible to solve this problem with a hardware timer?

[waclawek.jan]

Posted on November 07, 2015 at 22:03

This is almost the same as measuring pulse width of PWM - see the PWM input sub-chapter of TIM chapter. The only difference is that you don't set capture2's source to channel 1, but each channel captures its own ''native'' input.

JW

[vincenthamp9]

Posted on November 08, 2015 at 11:52

This is one of the most basic examples of input captures possible. Configure a timer of your choice with a certain base time with a precision in range (so at least something as high as the highest possible delay time).

Choose two input channels (most timers have ~4) and configure them for input capture. Activate the interrupt of the channel which triggers the delayed signal and then compare the CCR registers of both channels for the actual delay.