Hi RAMON RAMIREZ,
Please don't worry, actually, after your board is powered on, the code will run automatically after POR reset.
But please note, even you don't use the reset button, in the reset pin, you still need to add 4.7K to 10K external pull-up resistor, and the 0.1uf capacitor to ground.
The reason why you use the frdm-kl03 after power on it, it seems it's not working, and press reset it is Ok, I think it is caused by the com port identification in the PC, after power on, the PC still not find the COM port, you need to search the com port in the PC at first, after it connected, your serial assistant will find the according uart data.
Actually, if you use the oscilloscope to check the lpuart wave after power on, you will get the according uart wave, it means the code is running automatically.
Wish it helps you!
If you still have question, please let me know!
Have a great day,
Kerry
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