Hi Zhai ling,
About the K64 pit usage, please refer to our K64 sample code, which can be download from this link:
Welcome to Kinetis Expert | Kinetis Expert
Click build an SDK, then select the board as FRDM-K64F120M, generate the code and download it, you can find the PIT code in folder:
SDK_2.0_FRDM-K64F\boards\frdmk64f\driver_examples\pit

The code in red frame can realize 1S PIT delay.
Wish it helps you!
If you still have question, please let me know!
Have a great day,
Kerry
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