S32K146 FTM Signal measurement

[ShaoTianzhi]

Hello: 

I have some doubts about the ftm_signal_measurement_s32k146 project in the S32K146 Example Project. What is the meaning of the return value of the FTM_DRV_GetInputCaptureMeasurement function called in main.c of this project? Is it the number of rising edges of the input terminal during the period from the start of monitoring to the call of the function?

[Senlent]

Hi@ShaoTianzhi

sorry for the later reply,

no, return the time stamps when the rising edge event was captured.

[ShaoTianzhi]

Thank you for your answer ,I've got it.

Is this the return value in Detect edge signal mode? What is the difference between Measure input signal mode and Detect edge signal mode?

If I want to obtain the pulse frequency in real time according to the monitoring method shown in the figure, and count each pulse, can it be achieved using IC capture?

[Senlent · Accepted solution]

Hi@ShaoTianzhi

please refer to this post.

https://community.nxp.com/t5/S32K-Knowledge-Base/S32K1-Calculate-the-motor-speed-based-on-the-FTM/ta... 

The ICU module can be used to capture each rising or falling edge of the input waveform and record the timestamp of the trigger edge, which can be used to calculate the period and frequency of the waveform, etc.