DocID024597 Rev 3 719/1693
RM0351 Advanced encryption standard hardware accelerator (AES)
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Figure 173. ECB decryption mode
25.5.2 Cipher block chaining (CBC)
In cipher-block chaining (CBC) mode, each block of plain text is XORed with the previous
cipher text block before being encrypted. To make each message unique, an initialization
vector (AES_IVRx) is used during the first block processing.
The initialization vector is XORed after the swapping management block during encryption
mode and before it in decryption mode (refer to Figure 174 and Figure 175).
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