Si102x/3x
14.6.4. CBC Decryption
The AES0 module data flow for CBC decryption is shown in Figure 14.6. The ciphertext is written to
AES0BIN. For the first block, the initialization vector is written to AES0XIN. For subsequent blocks, the
previous block ciphertext is written to AES0XIN. AES0DCFG is configured to XOR AES0XIN with the AES
core data output. The XOR on the input is not used. The AES core is configured for a decryption operation.
The decryption key is written to AES0KIN. The key size is set to the desired key size.
AES0BIN
internal state
machine
AES0XIN
+
AES0DCFG
Data In
AES0KIN
Key
In
AES
Core
Data Out
Key
Out
AES0BCFG
+
AES0YOUT
Figure 14.6. CBC Decryption Data Flow
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Rev. 0.3
SILABS [ SILICON LABORATORIES ]
