S32K144 Watchdog accruacy

[Hoon]

Hi.
I'm designing Watchdog using S32K144 and my settings are as follows
My intentions are as follows
2048(Timeout Value) / (128kHz(LPO) / 256(Prescaler)) = 4.096s
But, The actual Watchdog occurs approximately 4.7s later. (Test will be conducted after Watchdog count clear).
Even considering Accuracy of LPO, there is a big difference between 4.096s and 4.7s, is there any way to improve this?

[Watchdog setting]

Read only : Yes
Prescaler Enable : Yes
Update Enable : Yes
Interrupt Enable : Yes
Window Enable : No
Window Value : 0       [clock cycles]
Timeout Value : 2048 [clock cycles]
Wait Mode : No
Stop Mode : No
Debut Mode : No

[Robin_Shen]

Hi

I changed the configuration of wdog_interrupt_s32k144_SDK403 based on your tips.  

That project will feed the dog 8 times in the WDOG interrupt, and each time it feeds the dog, it will flip PTD15. After that, it will no longer feed the dog and wait for the watchdog reset.
I measured the time from the last time the dog was fed(flip the PTD15) to the next reset was about 4s.

My test result is different from yours, I recommend testing the SDK example.

Best Regards,
Robin
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