Cannot access Memory (@0xe00ffff0,Read,Acc Size:4byte) on MK64 MCU

[hr_gopalgowda]

Hello every one 

I'm using 

IDE : Keil V5.25.2.0

using latest software package : Keil.Kinetis_K60_DFP.1.5.0

MCU : MK64FN1M0VLL12 microcontroller on which security as been enabled (i.e FSEC reg value 0x54).

When I try to Flash using Ulink2 Debugger I am getting following error : Cannot access Memory (@0x00ffff0,Read,Acc size: 4byte):

The MCU core is getting detected by the Kiel target.

When we enter load the program it asks for the Mass erase (As per the User guide the after Mass erase MCU loses its security) when click on Ok for Mass Erase the following error pop up.

I have tried Resetting MCU and Program the flash still same issue.

But when I tried J-tag the MCU core is not detecting in Keil target debug menu.

please help me to resolve this error, We lost many device due to this.

Thanks and Regards, 

Gopal Gowda.

[Pavel_Hernandez]

Hello, my name is Pavel, and I will be supporting your case, it would be possible to know the configuration used on the FREC? before this issue. There is a possibility that the MCU is locked.

Best regards,
Pavel

[hrGopalGowda]

Hi Pavel,

Thank you for your support,

FSEC reg value is configured to 0x54 before observing this issue.

Thanks and Regards

Gopal Gowda H R

[Pavel_Hernandez]

Hello, if you have this configuration 0x54.

b00: MCU security status is secure
b01: factory access denied
b01: Mass erase enable
b01: Backdoor Key access disable

I recommend changing to the default state, doing a mass erase, and testing it again with a simple Blink LED if the flash is not successful the MCU may be and will stay in brick mode.

I know you explore these steps but review the thread maybe could help you.

Resurrecting ‘bricked’ NXP Kinetis Devices | MCU on Eclipse

Best regards,
Pavel