topic Re: Flash protection for KEA128 in Kinetis Microcontrollers

Flash protection for KEA128

adarrow — Tue, 14 May 2019 10:59:17 GMT

Hello,

I think I may already know the answer to this question but I thought it might be worth confirming:

I am working with the KEA128 and what I'd like to do is protect the first 32k of flash (0x0000 to 0x7FFF) for bootloader purposes. Is this possible?

Looking at the KEA128 Sub-Family Reference Manual, it appears that I could protect the first 16k, then the next 8k can't be protected, but then the 8k after that can be protected.

Any help would be appreciate, thanks!

Re: Flash protection for KEA128

mjbcswitzerland — Tue, 14 May 2019 15:43:08 GMT

Andrew

Correct, the protection scheme in the KEA128 is strange in comparison to the one used in other Kinetis parts.

If your boot loader is <= 24k you can put the code in the areas that can be protected.
If you could reduce the loader's size to <= 16k it would be easier.

Which loader are you using?

I have KEA128 UART loaders that need < 8k (Kboot compatible UART) or SREC/iHEX < 8k.

Regards

Mark

- http://www.utasker.com/kinetis/TRK-KEA128.html
- http://www.utasker.com/kinetis/FRDM-KEAZ128Q80.html

Re: Flash protection for KEA128

adarrow — Tue, 14 May 2019 16:22:50 GMT

Hi Mark, thanks for confirming my understanding.

Fortunately our bootloader is currently < 16k so we can use the 16k block. If entire first 32k was protectable, we would have considered reserving that for possible future needs.

We are using a custom bootloader that uses a proprietary communication protocol (uses LIN hardware) for accepting new application code.