AT88SC153-10SU-00 Atmel, AT88SC153-10SU-00 Datasheet - Page 14

• Manufacturer Part Number: AT88SC153-10SU-00
• Description: IC EEPROM 2KBIT 1MHZ 8SOIC
• Manufacturer: Atmel
• Series: CryptoMemory®r

Specifications of AT88SC153-10SU-00

• Format - Memory: EEPROMs - Serial
• Memory Type: EEPROM
• Memory Size: 2K (256 x 8)
• Speed: 1MHz
• Interface: Serial
• Voltage - Supply: 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

9.7
9.8
14
Initialize Authentication
Verify Authentication
AT88SC153
Figure 9-7.
Note:
The Initialize Authentication command sets up the random generator with the cryptogram (Ci),
the secret seed (Gc), and the host random number (Q). Once the sequence is completed and a
stop condition is issued, there is a nonvolatile write cycle to clear a new bit of the AAC. In order
to complete the authentication protocol, the device requires the host to perform an ACK polling
sequence with the specific command byte of $B6, corresponding to the Verify Authentication
command.
Figure 9-8.
Note:
If Q1 is equal to Ci + 1, then the device writes Ci + 2 in memory in place of Ci; this must be pre-
ceded by the Initialize Authentication command. Once the sequence is completed and a stop
condition is issued, there is a nonvolatile write cycle to update the associated attempts counter.
In order to know whether or not the authentication was correct, the device requires the host to
perform an ACK polling sequence with the specific command byte of $BD, to read the corre-
sponding attempts counter in the configuration zone. A valid authentication will result in the AAC
cleared to $FF. An invalid authentication attempt will initiate a nonvolatile write cycle, but no
clear operation will be performed on the AAC.
Q: Host random number, 8 bytes
Q1: Host challenge, 8 bytes
Initiatize Authentication
Verify Authentication
1
Q1(0)
Q1(1)
Q1(7)
1016E–SMEM–12/07