I am sorry for any misunderstanding.
The MCUBootUtility (created by one of our colleagues) it is an optional tool to erase and program the RT while we try to regain debug access. The MCUXpresso and the J-link tools can also be used , but they work over SWD/ JTAG. Sometimes we could face issues with SWD, therefore using UART/USB protocols (MCUBootUtility) we can communicate with the RT
We typically recommend set the i.MX RT processors into serial downloader mode, to regain debug access, this step when the RT enters this mode, the main application is no longer booted, also in this mode could be easier to perform a mass erase and update a new application. This process can be done using SWD (J-link) or UART/USB (MCUBootUtility). The deal here is stop the main application using the serial downloader mode, clean the older application and debug the new one.
The steps to do it is:
- Set your board in serial downloader mode
- Erase the flash
- Load new image, using any of two
- Using MCUXpresso
- Set your board in internal mode
- Trigger a new debug session
- Using NXP-MCUBootUtility
- Instruction in the link
- Load a new image
you can choose the version of MCUXpresso that you want to use in the following page: Design : Product Information : MCUXpresso IDE (flexnetoperations.com)
I hope this information help you!!