Waveform from FTM is somethin strange

[kiyoshimatsuzak]

Hi, all.

I tried to use FTM of K64F on my original board.

My software using KSDK changes the frequency from 400Hz to 4000Hz.

When the software change the frequency, we got strange pulse in the waveform.

I tried some circuit and captured each output waveforms of FTM.

I attaced figures of waveform, please confirm this.

1. 

I'd liket to erase strange pulse.

If anyone has any advices, please let me know.

2.

I could find block diagram in the K64F manual.

But I need an internal circuit of K64F's FTM.

If anyone has this circuit diagram, please give it to me.

Regards, Kiyoshi Matsuzaki

[Hui_Ma]

Hi

I also do a test with FRDM-K64F board, using PTC1 pin output 50% duty cycle square signal without find your mentioned issue.

I don't test PTC1 pin with SN74LS07 device, I test with 4.7Kohm pull-up and pull down.

With the 4.7Kohm pull-up resistor, I don't find your mentioned issue.

Could you provide your test code? Thanks.

Wish it helps.

Have a great day,
Ma Hui
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