KM34Z75M Maintenance Mode

[KKR231]

Hi

I have TWR-KM34Z75M board and it goes under Maintenance mode. Can you please guide to resolve it. 

I tried and logs of that 

"Type "connect" to establish a target connection, '?' for help
J-Link>connect
Please specify device / core. <Default>: MKM34Z256XXX7
Type '?' for selection dialog
Device>?
Please specify target interface:
J) JTAG (Default)
S) SWD
T) cJTAG
TIF>S
Specify target interface speed [kHz]. <Default>: 4000 kHz
Speed>
Device "MKM34Z256XXX7" selected.

Connecting to target via SWD
InitTarget()
SWD selected. Executing JTAG -> SWD switching sequence.
Connect Under Reset
SWD selected. Executing JTAG -> SWD switching sequence.
Readout protection is set and mass erase is disabled. J-Link cannot unprotect the device.
Found SW-DP with ID 0x2BA01477
Failed to power up DAP
InitTarget()
SWD selected. Executing JTAG -> SWD switching sequence.
Connect Under Reset
SWD selected. Executing JTAG -> SWD switching sequence.
Readout protection is set and mass erase is disabled. J-Link cannot unprotect the device.
Found SW-DP with ID 0x2BA01477
Failed to power up DAP
Cannot connect to target."

Thankyou

[Pavel_Hernandez · Accepted solution]

Hello, my name is Pavel, and I will be supporting your case, I reviewed your information, and the mode of Maintenance Mode sometimes is when the MK20 (debugger) of the frdm is prepared to update the firmware.

*So, this thread could help you the debugger on the board, to get out of the maintenance mode.

OpenSDA Serial and Debug Adapter | NXP Semiconductors

*The other part of the message from the JLink Commander mentioned is not possible to communicate via SWD with the target because is locked.

Readout protection is set, and mass erase is disabled. J-Link cannot unprotect the device.

The JLink commander cannot establish the communication, the MCU is lock, to get more details about the level of this will need to read the FSEC register, notice if the back door key is available to recovery the MCU, the other way the MCU could be stay in brick mode.

Here you can read more about the FSEC register.

Using Kinetis Security and Flash Protection Features (nxp.com)

Best regards,
Pavel