ST STM32WL55JC User Manual

RM0453 Rev 2 687/1454
RM0453 AES hardware accelerator (AES)
695
23.7.2 AES status register (AES_SR)
Address offset: 0x04
Reset value: 0x0000 0000
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res.
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. Res. BUSY WRERR RDERR CCF
rrrr
Bits 31:4 Reserved, must be kept at reset value.
Bit 3 BUSY: Busy
This flag indicates whether AES is idle or busy during GCM payload encryption phase:
0: Idle
1: Busy
When the flag indicates “idle”, the current GCM encryption processing may be suspended to
process a higher-priority message. In other chaining modes, or in GCM phases other than payload
encryption, the flag must be ignored for the suspend process.
Bit 2 WRERR: Write error
This flag indicates the detection of an unexpected write operation to the AES_DINR register (during
computation or data output phase):
0: Not detected
1: Detected
The flag is set by hardware. It is cleared by software upon setting the ERRC bit of the AES_CR
register.
Upon the flag setting, an interrupt is generated if enabled through the ERRIE bit of the AES_CR
register.
The flag setting has no impact on the AES operation. Unexpected write is ignored.
Bit 1 RDERR: Read error flag
This flag indicates the detection of an unexpected read operation from the AES_DOUTR register
(during computation or data input phase):
0: Not detected
1: Detected
The flag is set by hardware. It is cleared by software upon setting the ERRC bit of the AES_CR
register.
Upon the flag setting, an interrupt is generated if enabled through the ERRIE bit of the AES_CR
register.
The flag setting has no impact on the AES operation. Unexpected read returns zero.
Bit 0 CCF: Computation completed flag
This flag indicates whether the computation is completed:
0: Not completed
1: Completed
The flag is set by hardware upon the completion of the computation. It is cleared by software, upon
setting the CCFC bit of the AES_CR register.
Upon the flag setting, an interrupt is generated if enabled through the CCFIE bit of the AES_CR
register.
The flag is significant only when the DMAOUTEN bit is 0. It may stay high when DMA_EN is 1.

ST STM32WL55JC Specifications

General

Brand	ST
Model	STM32WL55JC
Category	Microcontrollers
Language	English