SAM4L Datasheet, PDF (431/1185 Pages) ATMEL Corporation – ATSAM ARM-based Flash MCU

ATSAM4L4/L2
• CFBS: Cipher Feedback Data Segment Size
CFBS Description
0 128 bits
1 64 bits
2 32 bits
3 16 bits
4 8 bits
Others Reserved
See NIST Special Publications 800-38A, Recommendation for Block Cipher Modes of Operation - Methods and Techniques for
information on the CFB mode of operation.
See Section 18.4.2 on page 425 for information on operating AESA in the CFB mode.
• OPMODE: Confidentiality Mode of Operation
OPMODE Description
0
Electronic Code Book
1
Cipher Block Chaining
2
Cipher Feedback
3
Output Feedback
4
Counter
Others Reserved
See NIST Special Publications 800-38A, Recommendation for Block Cipher Modes of Operation - Methods and Techniques for
descriptions of the various confidentiality modes of operation.
See Section 18.4.2 on page 425 for information on operating AESA in these modes.
• DMA: DMA Mode
DMA
0
1
Description
Non-DMA mode
DMA mode
• ENCRYPT: Encryption
ENCRYPT
0
1
Description
Decryption
Encryption
42023C–SAM–02/2013
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