My application has a bootloader and appliation. Recently a new app version was release, which contained a bug.
Programming using the bootloader works ok, but when the application start it seems to crash.
Now it is rebooting in an endless loop and I cannot access the bootloader nor the app, unfortunately.
The application runs on a mc9s08dz60 and I have enabled the backdoor key (NVBACKKEY0-7) and KEYEN=1.
I also found out that I can connect my debugger (Cyclone Pro) in HotSync, using the attach debug session type.
It seems I can connect with my device, but obviously all I read back is 0.
Now, is there any way I can enter the backdoor key so I can step through my code finding the line where the code crashes?
I can access the key registers using the register window and I can also write them with the key I have.
But nothing seems to happen. I've read somewhere that you also need to set KEYEN=1, but the register containing it is readonly.
Any other possibility is also very welcome.