ZHCS926C May 2012 – May 2021 BQ34Z100
PRODUCTION DATA
To execute an authentication query in UNSEALED mode, a host must first write 0x01 to the BlockDataControl() command to enable the authentication data commands. If in SEALED mode, 0x00 must be written to DataFlashBlock().
Next, the host writes a 20-byte authentication challenge to the AuthenticateData() address locations (0x40 through 0x53). After a valid checksum for the challenge is written to AuthenticateChecksum(), the device uses the challenge to perform its own SHA-1/HMAC computation in conjunction with its programmed keys. The resulting digest is written to AuthenticateData(), overwriting the pre-existing challenge. The host may then read this response and compare it against the result created by its own parallel computation.