ATAES132-SH-EQ-T Atmel, ATAES132-SH-EQ-T Datasheet - Page 30

• 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

7.2.
AuthCheck Command
The AuthCheck command is used to check the OutMAC generated by the Auth command or the counter command on a
second ATAES132 device. This command can not check MACs created by other commands.
To use this command the nonce must be identical on both devices (see Section 7.21.1) and the MacCount must have the
same value. Both devices must also contain identical key values, but it is not necessary for the KeyID on the origin device to
match the KeyID on the destination device. In this section the device which generates the MAC is referred to as the origin
device; the device checking the MAC is referred to as the destination device.
If mode bit 5, 6, or 7 is 1b, then the associated usage counter, SerialNum register value, or the first four bytes of the
SmallZone register in the SecondBlock field must match the values on the origin device. The ManufacturingID register must
be identical on both devices, since it is always included in the MAC calculation.
A valid nonce is required to run the AuthCheck command. If the KeyConfig[MacKeyID].RandomNonce bit is 1b, then the nonce
must be random.
The AuthCheck command always sets the AuthComplete status flag to NoAuth.
Table 7-21. Input parameters
Table 7-22. 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
Data1
Data2
Data3
Name
ReturnCode
Name
AuthCheck
Mode
MacKeyID
Zero
FirstBlock
SecondBlock
InMac
(Bytes)
Size
1
Notes
Upon success, 0x00 will be returned. Any command execution or validation failure generates a
non-zero error code, per Section 6.3
(Bytes)
Size
11
16
16
1
1
2
2
Notes
0x15
The value of this field must match the mode field value used when executing
the Auth command or the counter command which generated the OutMAC on
the origin device
Upper byte is always 0x00. Lower byte is the pointer to the key.
Legal values: 0x00 to 0x0F, 0xFF
Always 0x0000
The value of this field must match the first authenticate-only block used to
calculate the MAC on the origin device
The value of this field must match the second authenticate-only block used to
calculate the MAC being checked on the origin device. If mode bits 5, 6, and 7
are 0b, then this field must be present, but is ignored.
MAC to be checked
Atmel ATAES132 Preliminary Datasheet
8760A−CRYPTO−5/11
30