S32K14x:Questions about EEP initial values

[ShaoTianzhi]

Hello:

    I want to confirm a problem, when I use the FlaxRAM of S32K146 or S32K142 chip as EEP, after partitioning, the initial value of the corresponding address segment must be 0xFF?

[Senlent]

Hi@ShaoTianzhi

for FLASH, the default state is 1 after erasing, and the process of program Flash is the process of writing 0

1.The FlexNVM used for EEE backup is not visiible to the CPU.

   User code cannot directly access (read or write) this address mapping area, otherwise a bus error will occur and enter the HardFault or BusFault, and at the same time, in the Memory window of the debugging interface, the EEE_Flash area is displayed in an unknown state(???)

2.The FlexNVM used for D-FLASH

   In the debugging interface, the D-Flash area is displayed in a normal state(default vaule 0xFF).

[ShaoTianzhi]

Hi@Senlent

Is the FlexRAM area simulated as EEP the same as the D-Flash area?

[Senlent]

Hi@ShaoTianzhi

I don't quite understand your question, what do you mean by the "same as the D-Flash area"?

[ShaoTianzhi]

When partitioning FlexNVM as a simulated EEP, is the default value of FlexRAM also 0xFF?

[Senlent]

Hi@ShaoTianzhi

The data as an EEP area is not visible to the user, so we don't know what the default value is.

[ShaoTianzhi]

However, when I debug, I can observe the data at this address, and I can also access the corresponding data through code.

[Senlent]

Hi@ShaoTianzhi

我以为你说的EEP是指EEPROM的备份区域。

当FlexRAM没被用作EEPROM的时候，它可以和普通的RAM一样在上电初始化的的时候写入任意值。

当FlexRAM被用作EEPROM的时候，你写入的FlexRAM的值会备份至EEPROM的备份区域（FlexNVM），你可以设置上电的时候默认将EEPROM备份区域的数据同步到FlexRAM,所以FlexRAM的值和EEPROM备份区的数据一样。而作为EEPROM的备份区域的数据对用户是不可见的。

https://mp.weixin.qq.com/s?__biz=MzI0MDk0ODcxMw==&mid=2247486584&idx=1&sn=3b8651b928edd19c642b17838a...

细节可以看上面链接中的文档。