S32KのトピックRe: LPO32K_CLK as watchdog clock

LPO32K_CLK as watchdog clock

adrianwenger — Thu, 06 Apr 2017 11:27:15 GMT

Hi,

i want to set the LPO32K_CLOCK as wdog clock source

Settings:

PMC->REGSC = PMC_REGSC_LPODIS(0); /* 0b - Low power oscillator enabled */

SIM->LPOCLKS = SIM_LPOCLKS_LPOCLKSEL(2); /* LPO32K_CLK Source */

WDOG->CS = WDOG_CS_CLK(1) /* Watchdog Clock --> 1b - LPO Clock */

This seetings shout normaly enable the 32 KHz LPO clock, but if i measure it, it seems to use still the 128 KHz LPO...

regards,

Adrian

Re: LPO32K_CLK as watchdog clock

danielmartynek — Mon, 10 Apr 2017 08:08:55 GMT

Hi,

The LPOCLKS register is a write-once register, and is reset only on POR or LVD.

So have tried writing to the register after POR?

Regards,

Daniel

Re: LPO32K_CLK as watchdog clock

adrianwenger — Mon, 10 Apr 2017 09:05:06 GMT

Hi ,

yes I immediatly set up the Watchdog After reset.

Regards,

Adrian

Re: LPO32K_CLK as watchdog clock

danielmartynek — Tue, 11 Apr 2017 14:37:31 GMT

Hi,

So, it doesn’t work even if you write to the LPOCLKS register after power-on-reset, when you unplugged the power supply. Has the content of the register changed? I have tried it and it works.

Regards,

Daniel

Re: LPO32K_CLK as watchdog clock

adrianwenger — Tue, 11 Apr 2017 15:51:00 GMT

Yes I setup the registers at the beginning of the Main Loop. Can you maybe post your example in here?

Thanks

Re: LPO32K_CLK as watchdog clock

danielmartynek — Wed, 12 Apr 2017 14:34:59 GMT

Hi,

I use a very simple code to set up the clock for the watchdog.

What is the exact problem? Are you able to set LPOCLKSEL bits?

If not, download the application to the MCU and then unplug power supply.

Connect it again and the register should be set.

Regards,

Daniel