at88sa102s ATMEL Corporation, at88sa102s Datasheet - Page 19

• Manufacturer Part Number: at88sa102s
• Description: Cryptoauthentication
• Manufacturer: ATMEL Corporation

4.4.
8584A–SMEM–03/09
GenPersonalizationKey
Loads a personalization key into internal memory and then uses that key along with an input seed to generate a
decryption digest using SHA-256. Neither the key nor the decryption digest can be read from the chip. Upon
completion, an internal bit is set indicating that a secure personalization digest has been loaded and is ready for use by
BurnSecure. This bit is cleared (and the digest lost) when the watchdog timer expires or the power is cycled.
This command will fail if Fuse[0] has been burned.
Table 15.
Table 16.
The SHA-256 message body used to create the resulting digest internally stored in the chip consists of the following
512 bits:
Opcode
Param1
Param2
Data
Success
256 bits
64 bits
127 bits
1
64 bits
Name
bits
Input Parameters
Output Parameters
GenPers
Zero
KeyID
Seed
Size
PersonalizeKey[KeyID]
Fixed value of all 1’s
Seed from input stream
‘1’ pad
Length of message in bits, fixed at 512
Name
1
Upon successful execution of HOST0, a value of 0 will be returned by the AT88SA102S.
Size
16
1
1
2
0x20
Must be 0x00
Identification number of the personalization key to be loaded.
Seed for digest generation. The least significant bit of the last byte is
ignored by the AT88SA102S.
AT88SA102S [Preliminary]
Notes
Notes
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