MPC5554 internal FLASH error

[schlosserolivie]

Hello,

During the execution of my software the internal FLASH of the MPC5554 is became unreadable (Bus error using TRACE32 debugger). I do not know this can be possible as my software should not have executed any function to ERASE/WRITE the flash.

The unreadable FLASH is from address 0xD0000 to 0x1C0000. My software was not executed into one of this bloc of FLASH.

Do someone know which actions can set the FLASH into an invalid value ?

Regards

Olivier

[phaneeshm]

Hi,schlosserolivier

Please check your MMU  configuration,even check the Clock,some times i had faced the similar problem once then we came to know that we were running @wrong JTAG clock,but one thing am not sure if the flash is secured then you can not do any thing.

Once we shorted the both address lines and data lines unknowingly that was causing the BUS NOISE.I recommend you to check hardware lines once.

Thanks

[lukaszadrapa]

Hi,

I can see three possible problems:

1. MMU configuration - have you changed anything in MMU?

2. FLASH_BIUCR configuration - are you updating the number of wait states for flash (APC, WWSC, RWSC)?

3. Programming of non-erased flash - as you wrote, that's probably not the case.

Is it possible to read the flash after reset? Did you step the code? Is there any specific command/instruction that makes it unreadable? Once the flash becomes unreadable, is it possible to read the flash after next reset?

Regards,

Lukas