STMicroelectronics STM32F405

Cryptographic processor (CRYP) RM0090
724/1731 DocID018909 Rev 11
Figure 226 and Figure 227 illustrate AES-CTR encryption and decryption, respectively.
Figure 226. AES-CTR mode encryption
1. K: key; C: cipher text; I: input Block; o: output block; Ps: plain text before swapping (when decoding) or
after swapping (when encoding); Cs: cipher text after swapping (when decoding) or before swapping (when
encoding); P: plain text; IV: Initialization vectors.
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