GD32W51x User Manual
944
01: 192-bit key length
10: 256-bit key length
11: never use
7:6
DATAM[1:0]
Data sw apping type mode configuration, must be configured w hen BUSY = 0
00: No sw apping
01: Half -w ord sw apping
10: Byte sw apping
11: Bit sw apping
5:3
ALGM[2:0]
Encryption/decryption algorithm mode bit 0 to bit 2
These bits and bit 19 of CAU_CTL must be configured w hen BUSY = 0
0000: TDES- ECB w ith CAU_KEY1, 2, 3.
Initialization vectors (CAU_IV0..1) are not used
0001: TDES-CBC w ith CAU_KEY1, 2, 3.
Initialization vectors (CAU_IV0) is used to XOR w ith data blocks
0010: DES-ECB w ith only CAU_KEY1
Initialization vectors (CAU_IV0..1) are not used
0011: DES-CBC w ith only CAU_KEY1
Initialization vectors (CAU_IV0) is used to XOR w ith data blocks
0100: AES-ECB w ith CAU_KEY0, 1, 2, 3.
Initialization vectors (CAU_IV0..1) are not used
0101: AES-CBC w ith CAU_KEY0, 1, 2, 3.
Initialization vectors (CAU_IV0..1) are used to XOR w ith data blocks
0110: AES_CTR w ith CAU_KEY0, 1, 2, 3.
Initialization vectors (CAU_IV0..1) are used to XOR w ith data blocks
In this mode, encryption and decryption are same, then the CAUDIR is
disregarded.
0111: AES key derivation for decryption mode. The input key must be same to that
used in encryption. The BUSY bit is set until the process has been finished, and
CAUEN is then cleared.
1000: Galois Counter Mode (GCM). This algorithm mode is also used for GMA C
algorithm.
1001: Counter w ith CBC-MAC (CCM).
1010: Cipher Feedback (CFB) mode
1011: Output Feedback (OFB) mode
2
CAUDIR
CAU direction, must be configured w hen BUSY = 0
0: encryption
1: decryption
1:0
Reserved
Must be kept at reset value.
27.9.2.
Status register 0 (CAU_STAT0)
Address offset: 0x04