Green blinking at first debugger halt

Hello,

I just observed some strange/interesting behaviour. On one of our products there is a green LED connected to Pin 3 of GPIO port 0 on the nRF5340. When I connect the Ozone Debugger through my jlink, Ozone has flashed the Image and is waiting now to start the application, this LED is blinking at About 1Hz.

This blinking happens until I initialize the Hardware and switch the LED off. When I later reset inside Ozone, I got this blinking again.

I'm not 100% sure how far the Debugger runs at first connect. Does it really run until main() is started? I put a breakpoint inside the reset.S file directly at the start Code. But even when the Debugger stopps there (only after I've pressed run) the LED is already blinking.

This Problem is not a Show stopper for our product, but I found it interesting and would like to know what happens there and where could this blinking come from.

Regards
Erwin

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