SLUUCP8 June 2024 BQ41Z50
This command enables the update of the authentication key into the device. The BQ41Z50 device must be in FULL ACCESS mode for the authentication key to update.
To update a new authentication key:
There is no direct read access to the authentication key. After writing the new authentication to the gauge, the gauge will generate an all-zero challenge and provide the corresponding response for verification.
To verify the new authentication key:
The BQ41Z50 device also includes the capability to store the authentication key in secure memory. This is controlled using the SHA1_SECURE data flash bit; however, the authentication key cannot be written into the device using AuthenticationKey() as described above. It must be programmed using a separate method. Also, when using secure memory, the authentication key can only be written once and cannot be changed after it is written.