MKL27 waits ca. 3Sec befor Startup

[TheMnemonic]

After working with the KL25z without any problems, I had to change to the KL27z. Now while I have no problems at programming the KL27z I have a very strange effect which I don't know where I have to search.

Every program I write (and also the example Codes) will wait for 3 Secs after reset, before starting up and executing. Now my first thought was that this is caused by the bootloader. So I changed the FTFx_FOPT in the Flash Configuration in the startup_MKL27Z644.S. Unfortunately this didn't change the waiting startup behavior.

Does anyone else experience this behavior at startup? Or does anyone have an explanation for this behavior?

How do I have to disable this behavior?

Thanks in advance.

[mjbcswitzerland]

Hi

It probably still has something to do with the ROM loader not been fully/correctly deactivated, or the NMI pin not being disabed.

Try a reference binary from http://www.utasker.com/kinetis/FRDM-KL27Z.html which shows that an immediate start is possible - then compare the flash settings that it has (eg. using debugger) with the ones that you use to identify any differeces.

Regards

Mark