
NUC970 Technical Reference Manual
Publication Release Date: Dec. 15, 2015
- 979 -
Revision V1.30
NUC97
0
T
E
CHNIC
A
L
RE
F
E
RE
N
CE
MA
NUA
L
[21]
BLKSWAP
TDES/DES Engine Block Double Word Endian Swap
0 = Keep the original order, e.g.
{WORD_H, WORD_L}
.
1 = When this bit is set to 1, the TDES engine would exchange high and low
word in the sequence
{WORD_L, WORD_H}.
[20:17]
Reserved
Reserved.
[16]
ENCRPT
TDES/DES Encryption/Decryption
0 = TDES engine executes decryption operation.
1 = TDES engine executes encryption operation.
[15:11]
Reserved
Reserved.
[10:8]
OPMODE
TDES/DES Engine Operation Mode
0x00 = ECB (Electronic Codebook Mode).
0x01 = CBC (Cipher Block Chaining Mode).
0x02 = CFB (Cipher Feedback Mode).
0x03 = OFB (Output Feedback Mode).
0x04 = CTR (Counter Mode).
Others = CTR (Counter Mode).
[7]
DMAEN
TDES/DES Engine DMA Enable Control
0 = TDES_DMA engine Disabled.
TDES engine operates in Non-DMA mode, and get data from the port
CRPT_TDES_DATIN.
1 = TDES_DMA engine Enabled.
TDES engine operates in DMA mode, and data movement from/to the
engine is done by DMA logic.
[6]
DMACSCAD
TDES/DES Engine DMA with Cascade Mode
0 = DMA cascade function Disabled.
1 = In DMA Cascade mode, software can update DMA source address
register, destination address register, and byte count register during a
cascade operation, without finishing the accelerator operation.
[5]
DMALAST
TDES/DES Engine Start for the Last Block
In DMA mode, this bit must be set as beginning the last DMA cascade
round.
In Non-DMA mode, this bit must be set as feeding in last block of data.
[4]
Reserved
Reserved.
[3]
3KEYS
TDES/DES Key Number
0 = Select KEY1 and KEY2 in TDES/DES engine.
1 = Triple keys in TDES/DES engine Enabled.
[2]
TMODE
TDES/DES Engine Operating Mode
0 = Set DES mode for TDES/DES engine.
1 = Set Triple DES mode for TDES/DES engine.
[1]
STOP
TDES/DES Engine Stop
0 = No effect.
1 = Stop TDES/DES engine.
Note:
The bit is always 0 when it
’s read back.