topic Re: TPM don't work well when MOD=1 in Kinetis Microcontrollers

TPM don't work well when MOD=1

wenxue — Thu, 09 Mar 2017 07:22:33 GMT

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.

Re: TPM don't work well when MOD=1

Robin_Shen — Tue, 14 Mar 2017 02:26:01 GMT

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

Re: TPM don't work well when MOD=1

wenxue — Tue, 14 Mar 2017 02:47:02 GMT

Thanks very much.

Re: TPM don't work well when MOD=1

wenxue — Mon, 20 Mar 2017 02:26:37 GMT

hello Robin,

Do you have any update?

Re: TPM don't work well when MOD=1

Robin_Shen — Mon, 20 Mar 2017 02:39:08 GMT

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

Re: TPM don't work well when MOD=1

Robin_Shen — Thu, 23 Mar 2017 22:12:37 GMT

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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Re: TPM don't work well when MOD=1

wenxue — Fri, 24 Mar 2017 00:15:46 GMT

Hi Robin,

Got it, thanks!

Best Regards,

Wenxue

Re: TPM don't work well when MOD=1

wayne_wang — Sat, 25 Mar 2017 00:55:53 GMT

could please share customer information, thanks a lot!