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After the image is loaded, keys are generated and signed, a set of fuse bit values is generated and exported to a .json file
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Browsing OTP File
NXP Flasher for OTP programming accepts two file types:
.bin file of fixed size 256 bytes
.json file generated in the "OTP Configuration" window in MCUXpresso Secure Provisioning.
The OTP file is loaded by clicking the 
button. In the pop-up window, you can specify one of two file types.
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If a .json file is selected then .json file is loaded, it is automatically converted into a 256 byte binary file. The resulting binary file is saved under the same name and path as the .json file.
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Viewing and modifying an OTP file and viewing current MCU OTP status
After OTP file loading it is possible to preview and modify the fuse values in a dedicated window "Setup -> OTP Configuration". The window displays a list of fuse bits that are relevant to programming.
The "Current Value" column shows the fuse word values read from the selected target.
The "Required Value" column displays the fuse word values loaded from the OTP file
The window does not display all words at once, to view subsequent values, select the appropriate page by checking the checkbox "Page 1" or "Page 2".
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