MPC5674F Shadow flash password

[vincentbergeron]

Hi,

I recently programmed the MPC5674 and found ou afterwards that the shadow flash was compromised (don't know the cause yet).  Is it possible to reset the device (erase everything and reset default passwords).  I use it with the Axiom mpc567XDAT516 evaluation board.

Regards

[lukaszadrapa]

Hi,

once the device is locked by censorship mechanism and you haven't implemented any backdoor access, the device is locked forever. There's no option to recovery the device by mass erase. This option is supported on 16bit S12(X) devices, for example, but not on MPC5.

Take a look at:

http://www.freescale.com/files/32bit/doc/app_note/AN3787.pdf

Next option is that the code which is already programmed in flash checks the state of censorship. If the device is unexpectedly secured or command from external world is received (via UART or whatever), the code can re-program the shadow flash. But the code must be programmed to flash BEFORE the device is locked, of course.

Regards,

Lukas