56F84763: How to activate NVM special mode. Or how else can I change flash protection during runtime

[sfe]

Hello again,

currently I'm working on writing user data to flash, erasing it, reading it. All of that works fine.

The next step ist to protect the flash pages I use. This might not seem neccessary. But when using a 56F82xxx uC (without FlexNVM) the user data will lie behind the user applikation. And my bootloader is not supposed to erase the user data when he updates the firmware. And to avoid that in any case I want to protect the user data. Setting the protection in the FCF area works fine.

So, my actual question is: how can I change protection settings for program and/or data flash during runtime? The ref manual says it is only possible in NVM special mode. But it nowhere tells me  how to activate that mode. So how can I activate it? And is changing protection settings possible without the "special mode"?

Thanks and regards,

Sebastian

[Code_Blue_117]

I am trying to save runtime data (pairing IDs) to Flash section 0x00040000-0x0040004. I checked the configuration and the section is protected. In order to disable protection, I must be in NVM Special Mode, correct? Are you saying that it is impossible for me to save user data during run-time to my flash memory?

[albert_zhou]

I have the same issue with MKL27Z64VFM4 chip. I have to save calibration data from time to time. The NVM normal mode cannot protect the flash data. It is a big problem when you store the data unprotected. 

There should be other way to write and protect them like other EEPROM.

[TICS_Fiona]

Hello Sebastian

NVM Special mode is not a mode for the customer to use.

Please use the Normal Mode of the NVM.

Best Regards

Fiona Kuang

Technical Information & Commercial Support