AT32F425
Series Reference Manual
2022.03.30
Page 73
Ver 2.01
Figure 5-5 System data area programming process
OBF = 0?
Set the USDPRGM bit = 1 in
FLASH_CTRL
Write word/half-word
(32bits/16 bits) data
No
Yes
Start
Check the OBF bit in
FLASH_STS
No
Check the OBF bit in
FLASH_STS
OBF = 0?
Yes
Read PRGMERR bit and ODF bit
in FLASH_STS
End
5.4.4
Read operation
User system data area can be accessed through AHB bus of the CPU.
5.5
Flash memory protection
Flash memory includes access and erase/program protection.
5.5.1
Access protection
Flash memory access protection is divided into two parts: high-levela and lowe level.
Once enabled, only the Flash program is allowed to read Flash memory data. This read operation is not
permitted in debug mode or by booting from non-Flash memory.