In s32k118 Cant write FSEC bit Setting using T32

[mose]

Hi. nxp team

i'm trying to update FSEC bit to make my MCU jtag locking.

so I attempted startup.s code modifying like this,

and I checked my sec file that the FSEC register was updated at 400.

but even after data load on target, FSEC register still 0xFE, not 0xFC

It seems impossible to change the memory adress 0x0_0400

Please help me to resolve this issue.

Thanks,

MOSE

[lukaszadrapa · Accepted solution]

Hi Mose,

there's a protection against unintended modification of this flash configuration field.

The solution can be found in this file used for programming:

c:\T32\demo\arm\flash\s32k.cmm

Regards,

Lukas

[mose]

Thank you for your reply.

now i set my mcu to secure, but i have one more problem.. 

i want to unsecure my mcu using masserase in trace32,

so i setup mass erase command, MDM-AP Control Register[0] == 1

Data.Set EDBG:0x40000104 %Long 0x00000001

but it doesn't work. it still locking

Please help me to resolve this issue.

Thanks,

MOSE

[lukaszadrapa]

I can see two possible reasons:

- the mass erase is disabled in flash configuration field in FSEC by MEEN. This should be reflected also in bit 5 in MDM-AP Status register

- CSEc is enabled. This note can be found in description of Program Partition command:

Regards,

Lukas