TPM don't work well when MOD=1

[wenxue]

hello,

I want to use TPM as a common timer, but met a confusing phenomenon, when MOD=1, the period is not right.

hardware：FRDM_KL43Z

TPM clock source is OSCERCLK（32.768Khz）

I toggle a gpio in TPM timer ISR, When MOD=1, the frequency is wrong.  It will be right if MOD set for other values.

Thanks.

[wayne_wang]

could please share customer information, thanks a lot!

[Robin_Shen]

Hi Wenxue,

Sorry for the late reply.

See below information received from our AE:

this root cause is that it need to take 2 TPM clock cycle to syncTOF flag, so if set MOD = 1, counting time is too short, and it need to generate OVERFLOW 2 times till set the TOF flag.

will notice customer not to try set MOD to 1, and add note in reference manual.

Best Regards,

Robin

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[wenxue]

Hi Robin,

Got it, thanks!

Best Regards,

Wenxue

[Robin_Shen]

Hi Wenxue,

I test the project on FRDM-KL43Z board find the same phenomenon.

I will ask the Kinetis AE team for help on this case. And I will inform you as soon as I get any feedback.

Best Regards,

Robin

[wenxue]

hello Robin,

Do you have any update?

[Robin_Shen]

Sorry. I am still waiting for the reply from our AE.

You can see that case in our internal place:TPM don't work well when MOD=1

[wenxue]

Thanks very much.