ATAES132-SH-ER Atmel, ATAES132-SH-ER Datasheet - Page 35

• 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

7.6.
7.6.1.
Crunch Command
The crunch command processes a seed value and returns the result within a specified time. The command provides a 16 byte
input seed which is combined with the ManufacturingID register and processed with the internal hardware crunch calculator.
The calculation is performed within a specified time period.
The host system should read the response within a few milliseconds after the response is specified to be available and
compare the returned value to the expected result to determine if authentic Atmel hardware is present. The crunch algorithm
is proprietary and is available only in authentic Atmel hardware.
The crunch command does not use the AES engine or the nonce. Executing the crunch command does not change the
authentication status or cryptographic state of the device.
Crunch Response Time
The response to the crunch command is available after a period a time that is dependent on the count field value. A large
count value requires more time to process than a small count value. The expected response time for the crunch command is
computed using the following equation:
Table 7-30. Input parameters
Table 7-31. 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.
Opcode
Mode
Param1
Param2
Data
Name
ReturnCode
Result
((Count × 256) + 600)) × 1.25 microseconds
Name
Crunch
Mode
Count
Zero
Seed
(Bytes)
Size
16
1
Notes
Upon success, 0x00 will be returned
Any command execution or validation failure generates a non-zero error code, per Section 6.3
Result out
(Bytes)
Size
16
1
1
2
2
Notes
0x0B
Must be 0x00
Upper byte is always 0x00
Lower byte is the iteration count for the crunch engine
Always 0x0000
Input seed
Atmel ATAES132 Preliminary Datasheet
8760A−CRYPTO−5/11
35