ATAES132-SH-ER Atmel, ATAES132-SH-ER Datasheet - Page 54

• Manufacturer Part Number: ATAES132-SH-ER
• Description: EEPROM AES 32Kbit EE I2C
• Manufacturer: Atmel

Specifications of ATAES132-SH-ER

• Rohs: yes
• Maximum Clock Frequency: 1 MHz
• Operating Supply Voltage: 6 V
• Maximum Operating Temperature: - 40 C to + 85 C
• Mounting Style: SMD/SMT
• Package / Case: SOIC-8
• Interface Type: I2C
• Factory Pack Quantity: 2300

7.17.
7.17.1. Extended Key Memory Data Structure
KeyTransfer Command
The KeyTransfer command copies key data from the user memory into the VolatileKey register or into a key register in the key
memory. The KeyTransfer command allows a user zone to be utilized as an extended key memory.
Keys stored in the user memory cannot be utilized directly by the cryptographic commands – the keys must be transferred into
either the VolatileKey register or into a key register in the key memory EEPROM prior to use. The usage restrictions for keys
transferred into the VolatileKey register are transferred from the key data structure when the KeyTransfer command is
executed. Usage restrictions for keys transferred into the key memory are stored in the KeyConfig[TargetKeyID] register – the
KeyTransfer command does not alter the KeyConfig[TargetKeyID] register.
If KeyConfig[TargetKeyID].TransferOK is 0b then the key register cannot be updated with the KeyTransfer command.
If KeyConfig[TargetKeyID].TransferOK is 1b, then the KeyTransfer command can be used to update the Key register – the
KeyConfig[TargetKeyID].LinkPointer contains the user zone number of the extended key memory.
If ZoneConfig[UZ].AuthRead is 1b for the user zone number containing the key data structure, then prior authentication is
required using the KeyID stored in ZoneConfig[UZ].AuthID before a key can be transferred to either the VolatileKey register or
into a key register in the key memory EEPROM.
When a user zone is utilized as the extended key memory, the keys are stored in the 32 byte key data structure as shown in
Table 7-38. The first 16 bytes contain the key value, two bytes store the VolUsage restrictions, and the remaining bytes
should contain all zeros. The starting address of each key data structure is required to be the first byte of a 32 byte physical
page (see Section B.2).
Table 7-54. Key data structure in user memory
Table 7-55. Input parameters
Table 7-56. Output parameters
The command and response packet is transmitted as a block beginning with the count and ending with a packet checksum.
This block format is described in Section 6.1.
Address
XX00
XX10
Opcode
Mode
Param1
Param2
Name
ReturnCode
h
h
-XX0F
-XX1F
h
h
Name
KeyTransfer
Mode
TargetKeyID
Address
(Bytes)
Size
VolUsage
0
1
h
1
h
Notes
Upon success, 0x00 will be returned. Any command execution or validation failure generates a
non-zero error code, per Section 6.3.
2
h
(Bytes)
Size
1
1
2
2
3
h
4
Notes
0x1A
Must be 0x00
Upper byte is always 0x00. Lower byte is the location where the key will be
stored. Legal values: 0x00 to 0x0F (standard keys), 0xFF (volatile key).
Starting address of the key data structure in user memory
h
5
h
6
h
Reserved (All bytes 0x00)
7
h
Key
Atmel ATAES132 Preliminary Datasheet
8
h
9
h
A
h
B
h
C
h
8760A−CRYPTO−5/11
D
h
E
h
F
h
54