Need help locking and unlocking an LPC55S28JBD100 chip

[CPrice94]

I am working on a project that requires me to know how to lock and unlock an LPC55S28JBD100 microcontroller.  I have perused the user guides for the chip itself, the MCUXpresso IDE, the MCUXpresso Secure Provisioning Tool, and the user guide for the J-link probe I am using to connect to and read the flash content.

I am doing this on a development board from NXP for the LPC55S28 microcontroller.  When I first got the development board and flashed the chip using the IDE, I had to unlock it by using a J-link command.  The command worked and the chip was unlocked, but I need to know how to lock it again to recreate the process.

I would like to be able to write a program to the chip using the IDE, lock it, and then verify it can be unlocked using my J-link probe and the on-board SWD interface.

[Alice_Yang]

Hello @CPrice94 

What function do you want to lock for lpc55s28? SWD? 

BR

Alice 

[CPrice94]

Yes, I am wanting to use SWD to read the lpc55s28.  I am able to unlock it using the "unlock" command from J-Link Commander, so I know I can unlock it and then read the flash contents using SWD.

So if there is a way to lock the chip against SWD so I can unlock it again that would be the goal.

Thanks.

[Alice_Yang]

Hello @CPrice94 

Disable SWD can through SOCU_PIN and SOCU_DFLT: 

About detail you can refer to UM11126. And there is a demo from our SE team, I attached it for you.

Pay attention, the demo also disabled ISP .

BTW, how do you lock it before your unlock?

BR

Alice