topic How to program and erase shadow memory in MPC5xxx

How to program and erase shadow memory

1329306846 — Fri, 02 Feb 2018 02:06:06 GMT

Hello eyeryone！

Recently I 'm learning MPC5675K .I want to operate flash memory. There is present a shadow block in code flash memory module.I hope to program and erase shadow memory ,but I don't know how to operate it .
User mode program and erase of the shadow block are enabled .There are some registers listed in the below photo.

But I can't find in the project file of "MPC5675K.h".

Really hope to get your help !

Re: How to program and erase shadow memory

davidtosenovjan — Mon, 05 Feb 2018 12:15:19 GMT

Firstly I would like to strongly warn that shadow flash programming may be potentially dangerous because there is also censorship information there. Censorship feature is a way to prevent unauthorized access to the device. However it is very sensitive thing. It is needed to use it very carefully, because an inappropriate usage can lead in making the device useless. If user accidentally erases shadow flash/row there is no chance to recover it (unless it had been though about before).

I have two examples for censorship programming, however none for MPC5675K, Principle is similar, but there may be certain differences there:
Example MPC5604B Censorship CW210
Example MPC5644A Censorship CW210

My colleague also prepared similar one:
Example MPC5604B Shadow Flash Reprogramming

Also, I would recommend you to read application note "Preventing Device Lockout via Censorship on MPC55xx and MPC563x Families":
https://www.nxp.com/docs/en/application-note/AN3787.pdf

It is very good to have EVB with MCU socket for these experiments, because users very often broke their devices and then there is a need to MCU replacing.

Re: How to program and erase shadow memory

1329306846 — Sat, 03 Mar 2018 03:23:30 GMT

David Tosenovjan，

Thank you for your answer ! It's really appreciate. Now I tell you why I want to use it. There are two applications ( Bootloader and application) in the MCU. Sometimes MCU apply Bootloader and sometimes apply application. When I change Bootloader application to

other application , I want to transfer some information . It means that I want to store some imformations in a place that two applications all

can get it.

For example , there are two applications (A and B） in the MCU. I can make A to B and make B to A .I want to store some imformations

in a place that A and B all can get it .

Do you have a appropriate way to deal with it ? Really hope to get your help.