C8051F962-A-GM Silicon Labs, C8051F962-A-GM Datasheet - Page 179

• Manufacturer Part Number: C8051F962-A-GM
• Description: 8-bit Microcontrollers - MCU 128KB, DC-DC, AES DQFN76
• Manufacturer: Silicon Labs

Specifications of C8051F962-A-GM

• Rohs: yes
• Core: 8051
• Processor Series: C8051
• Data Bus Width: 8 bit
• Maximum Clock Frequency: 25 MHz
• Program Memory Size: 128 KB
• Data Ram Size: 8448 B
• On-chip Adc: Yes
• Operating Supply Voltage: 2.5 V to 3.3 V
• Operating Temperature Range: - 40 C to + 85 C
• Package / Case: DQFN-76
• Mounting Style: SMD/SMT
• Number Of Programmable I/os: 57
• Number Of Timers: 4

14.2. Key Inversion
The Key output is used to generate an inverse key. To generate a decryption key from an encryption key,
the AES core should be configured for an encryption operation. Dummy data and the encryption key are
written to the AES0BIN and AES0KIN sfrs respectively. The output multiplexer should be configured to out-
put the decryption key to the AES0YOUT SFR.
The dummy data may be zeros or arbitrary data. The content of the dummy data does not matter. But six-
teen bytes of data must be written to the AES0BIN sfr to generate the inverse key.
AES0DCFG
AES0BCFG
AES0KIN
internal state
Figure 14.2. Key Inversion Data Flow
machine
Key
In
Rev. 0.5
AES0BIN
Data Out
Data In
Core
AES
AES0YOUT
+
+
Key
Out
AES0XIN
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