ATAES132-SH-EQ-T Atmel, ATAES132-SH-EQ-T Datasheet - Page 19

• Manufacturer Part Number: ATAES132-SH-EQ-T
• Description: EEPROM AES 32Kbit EE SPI
• Manufacturer: Atmel

Specifications of ATAES132-SH-EQ-T

• Rohs: yes
• Maximum Clock Frequency: 10 MHz
• Operating Supply Voltage: 6 V
• Maximum Operating Temperature: - 40 C to + 85 C
• Mounting Style: SMD/SMT
• Package / Case: SOIC-8
• Interface Type: SPI
• Factory Pack Quantity: 4000

4.3.
VolatileKey Configuration
There is a seventeenth key register named VolatileKey that has a KeyID of 0xFF and is stored in the internal SRAM. This key
location can be written only with the KeyCompute command (see Section 7.13) or KeyLoad command (see Section 7.16). The
contents of the VolatileKey register are erased when the device is powered down, enters the sleep state or is reset.
When the VolatileKey register is loaded, restrictions are placed on its usage, which persist until the power is lost or the key is
reloaded. The definition of the VolUsage field is shown in Table 4-3.
Table 4-7.
Note:
VolUsage Field Name
AuthOK
EncryptOK
DecryptOK
RandomNonce
AuthCompute
LegacyOK
ExportOK
WriteCompute
DecRead
Reserved
1.
Definition of the VolUsage field bits in the KeyCompute or KeyLoad command at VolatileKey creation
Warning:
exhaustively run with selected input data to attack the VolatileKey. Requiring authentication prior to allowing
encryption makes these attacks more difficult. To implement this, the Auth, and RandomNonce bits must be set
to 1b, and the encrypt bits must be set to 10b or 11b when the VolatileKey is created.
Since the encrypt command does not include an input MAC, the encrypt command can be
Byte
0
0
0
0
0
0
0
1
1
1
1 to 2
2 to 7
Bit
0
3
4
5
6
7
0
1
Description
If 1b, then the Auth command can be run using this key
If 0b, then the Auth command is prohibited
If 00b, then the encrypt command is prohibited
If 01b, then the encrypt command can be run using this key without a prior
If 10b or 11b, then encrypt command can be run using this key only with a prior
If 1b, then the decrypt command can be run using this key
If 0b, then the decrypt command is prohibited
If 1b, then operations using this key require a random nonce (See Section 7.20).
If 0b, a fixed (input only) nonce is permitted
If 1b, then the AuthCompute command can be run using this key
If 0b, then the AuthCompute command is prohibited
If 1b, then the legacy command can be run using this key
If 0b, then the legacy command is prohibited
If 1b, then the VolatileKey can be encrypted and exported using the KeyExport
If 0b, then export of VolatileKey is prohibited
If 1b, then the WriteCompute command can be run using this key
If 0b, then the WriteCompute command is prohibited
If 1b, then the DecRead command can be run using this key
If 0b, then the DecRead command is prohibited
Reserved for future use. All bits must be 0b.
authentication
authentication using this key
command
(1)
Atmel ATAES132 Preliminary Datasheet
(1)
8760A−CRYPTO−5/11
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