Hi Viktor,
I prepared example code for you (in attachment).
I simply use power_mode_switch_s32k144 example code as a template and add there LPTIMER component.
The LPTIMER is configured for 10s interrupt, with 1KHz LPO input clock!

The main contains LPTIMER initialization:

And LPTIMER interrupt routine:

I configured and initialized also GPIO Blue LED (port D, pin 0) - just for testing purpose.
Please be aware that power_mode_switch in SDK0.8.4 sometimes behave strangely (ignore inputs from the terminal) because it waits for EOL char (\r or \n) – please use Enter button with number char for your power mode choice.
This example works like a charm with SDK0.8.5 due to minor changes in the main code:

When you load code into MCU, the LED should be GREEN. When you use any serial terminal and switch mode to any STOP mode like VLPS, the LED become RED.
The LPTIMER event every 10s wake-ups MCU from stop mode and change LED from RED to GREEN.
Wake-up is also possible by SW3 button on board.
I hope it helps you.
Have a great day,
Radek
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