Drive GPIO high at startup as soon as possible with the nRF54L15

[andrea@al2tech]

Hello,

in our new project we need to drive a GPIO high as soon as possible after startup.

I have tried with the PRE_KERNEL_1 priority for the device driver but still takes 500ms after POR.

Is there a way to boot faster or toggle the pin eralier?

Does 500ms make sense to booth Zepyhr on nRF54L15?

We are not using MCUBOOT at this stage but will do soon.

ideally we want to port the solution to mcuboot as well.

Kind Regards,

Andrea 

[Susheel Nuguru]

Hi Andrea,

It seems like 500ms is a bit too much. Are you using crystal LF and/or HF clocks. It is good to check if the clock calibration is taking that long time.

If you are using secure mode, then TF-M initialization is known to take time aswell. Did you try to use EARLY instead of PRE_KERNEL_1?