How can I use the Backdoor Comparison Key without Flash commands

[香龙朱]

   Hi, all

   In S32K-RM.pdf, I know how to use the backdoor key to unsecure the chip. But if the chip is secured and there's no porgram in it. How can I unsecure it with backdoor key? Is there any tools or applications?

   anyone can tell me?

Thanks!

[paul_lalthuamsa]

Hi Daniel,

I am using chip FS32K144HAMLL which is expected to have CSE, but i am facing of issue of Hardfault on access to PRAM.(attached pic, it stuck on PRAM)

Debugger used: segger j-link base.

Example program tried: 1_configure_part_load_keys project from AN5401SW.

I have check this same project on S32K144EVB (with on board PE debugger) which has chip label PS32K144UAVLLA, it works.

Waiting for your comment!!

The chip what i used on my board seen to have CSE

[ummerkunnummalk]

Hi paullalthuamsanga,

   Please check the PRAM base address in S32K144.h. It should be #define CSE_PRAM_BASE (0x14000800u).

[danielmartynek · Accepted solution]

Hi,

There is an example that shows use of the feature.

https://community.nxp.com/docs/DOC-335429 

Unfortunately, the backdoor key can be used to unlock the MCU by the FTFC command only.

If you want to unlock the MCU from outside, you need to mass erase the whole chip.

Regards,

Daniel