Datasheet

57.5.7 AES Key Word Register x
Name: AES_KEYWRx
Offset: 0x20 + x*0x04 [x=0..7]
Reset: –
Property: Write-only
Bit 31 30 29 28 27 26 25 24
KEYW[31:24]
Access
W W W W W W W W
Reset 0 0 0 0 0 0 0 0
Bit 23 22 21 20 19 18 17 16
KEYW[23:16]
Access
W W W W W W W W
Reset 0 0 0 0 0 0 0 0
Bit 15 14 13 12 11 10 9 8
KEYW[15:8]
Access
W W W W W W W W
Reset 0 0 0 0 0 0 0 0
Bit 7 6 5 4 3 2 1 0
KEYW[7:0]
Access
W W W W W W W W
Reset 0 0 0 0 0 0 0 –
Bits 31:0 – KEYW[31:0] Key W
ord
The four/six/eight 32-bit Key Word registers set the 128-bit/192-bit/256-bit cryptographic key used for AES
encryption/decryption.
AES_KEYWR0 corresponds to the first word of the key and respectively AES_KEYWR3/AES_KEYWR5/
AES_KEYWR7 to the last one.
Whenever a new key (AES_KEYWRx) is written to the hardware, two automatic actions are processed:
• GCM hash subkey generation
• AES_GHASHRx Clear
See Key Writing and Automatic Hash Subkey Calculation for details.
These registers are write-only to prevent the key from being read by another application.
SAM E70/S70/V70/V71 Family
Advanced Encryption Standard (AES)
© 2019 Microchip T
echnology Inc.
Datasheet
DS60001527D-page 1808