AT88SA10HS_10 ATMEL [ATMEL Corporation], AT88SA10HS_10 Datasheet - Page 16

• Manufacturer Part Number: AT88SA10HS_10
• Description: Atmel CryptoAuthentication Host Security Chip
• Manufacturer: ATMEL [ATMEL Corporation]

5.6.
16
Table 5-11. Input Parameters
Table 5-12. Output Parameters
The SHA-256 message body used to create the resulting digest internally stored in the chip consists of the
following 512-bits:
BurnSecure
Burns any combination of the first 88-fuse bits. Verification that the proper secret fuse bits have been burned must
occur using the MAC command – there is no way to read the values in the first 64-fuses to verify their state. The
24-status fuses can be verified with the Read command.
The fuses to be burned are specified by the 88-bit input map parameter. If a bit in the map is set to a ‘1’, then the
corresponding fuse is burned. If a bit in the map parameter is zero, then the corresponding fuse is left in its
current state. The first bit sent to Atmel
Note:
To facilitate secure personalization of the AT88SA10HS, this map may be encrypted before being sent to the
chip. If this mode is desired, then the Decrypt parameter should be set to one in the input parameter list. The
decryption (transport) key is computed by the GenPersonalizationKey command, which must have been run
immediately prior to the execution of BurnSecure. In this case, prior to burning any fuses, the input Map
parameter is XOR’d with the first 88-bits of that digest from the GenPersonalizationKey command. The
GenPersonalizationKey and BurnSecure commands must be run within a single Wake cycle prior to the expiration
of the watchdog timer.
The power supply pin must meet the V
fuses reliably. If V
burn time will be 250µs. If Vcc is less than 4.5V but greater than V
set to 0x8000 and the internal burn time will be 190ms per fuse bit burned. The chip does NOT internally check
the supply voltage level.
Atmel AT88SA10HS Host Authentication Chip
Opcode
Param1
Param2
Data
Name
Success
256-bits
127-bits
64-bits
64-bits
1-bits
Since a ‘1’ bit in the Map parameter results in a ‘0’ data value in the actual fuse array, the value in the Map parameter
should be the inverse of the desired secret or status value. See Section 1.2 for more details
Name
GenPers
Zero
KeyID
Seed
Size
CC
PersonalizeKey[KeyID]
Fixed value of all ones
Seed from input stream
‘1’ pad
length of message in bits, fixed at 447
1
is greater than 4.5V, then the BurnTime parameter should be set to 0x00 and the internal
Notes
Upon successful execution, a value of zero will be returned by Atmel AT88SA10HS
Size
16
1
1
2
BURN
®
Notes
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 Atmel AT88SA10HS
AT88SA10HS corresponds to Fuse[0] and so on up to Fuse[87].
specification during the entire BurnSecure command in order to burn
BURN
then the BurnTime parameter should be
8595F–SMEM–8/10