AT88SC0404C-PI Atmel, AT88SC0404C-PI Datasheet - Page 16

• Manufacturer Part Number: AT88SC0404C-PI
• Manufacturer: Atmel

Specifications of AT88SC0404C-PI

• Operating Temperature (max): 85C
• Operating Temperature (min): -40C
• Package Type: PDIP
• Mounting: Through Hole
• Pin Count: 8
• Operating Temperature Classification: Industrial
• Lead Free Status / RoHS Status: Not Compliant

5.
5.1.
5.1.1. Password Verification
5211C–SMIC–01/10
Atmel AT88SC0104/0204/0404/0808/1616/3216/6416/12816/25616C
Communication Security Modes
Communication between the device and host operates in three basic modes. Standard mode is the default mode for
the device after power-up. Authentication mode is activated by a successful authentication sequence. Encryption mode
is activated by a successful encryption activation following a successful authentication. Data transferred to and from the
device is handled per the following table.
Table 14. Communication Security Modes
Note:
Security Operations
The use of passwords protects read and write accesses to the user zones. Any one of eight password sets is available
for assignment to any user zone through configuration of access registers. Atmel
24-bit passwords for read and write operations. Read passwords grant only read accesses to zones under password
protection, while write passwords grant both read and write accesses. Successful presentation of any password
renders the verify password command active until the presentation of another password or device reset. Only one
password may be active at a time. Presenting incorrect passwords decrements the value of the corresponding
password attempts counter (PAC). Decrementing the PAC to $00 permanently disables the corresponding password
and permanently renders the corresponding user zone(s) under protection inaccessible. Operation in authentication or
encryption mode requires encryption of passwords for all password transactions.
Figure 3. Password Verification
Standard/Password
Authentication
CryptoMemory Device
Encryption
Configuration data includes the entire configuration memory except the passwords
MAC: Message Authentication Code
Mode
VERIFY Password
Allow Access
Configuration Data
clear
clear
clear
Command/Communications
User Data
encrypted
Verify Password
clear
clear
Passwords
encrypted
encrypted
clear
®
Send Password
CryptoMemory
encrypted if performed after
Mutual Authentication
Data Integrity Check
Host Logic
®
MAC
MAC
N/A
provides separate
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