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Embedded Flash memory interface
3.8.2
Flash key register (FLASH_KEYR)
The Flash key register is used to allow access to the Flash control register and so, to allow
program and erase operations.
Address offset: 0x04
Reset value: 0x0000 0000
Access: no wait state, word access
31
30
29
28
w
w
w
15
14
13
12
w
w
w
Bits 31:0 FKEYR: FPEC key
The following values must be programmed consecutively to unlock the FLASH_CR register
and allow programming/erasing it:
3.8.3
Flash option key register (FLASH_OPTKEYR)
The Flash option key register is used to allow program and erase operations in the user
configuration sector.
Address offset: 0x08
Reset value: 0x0000 0000
Access: no wait state, word access
31
30
29
28
w
w
w
15
14
13
12
w
w
w
Bits 31:0 OPTKEYR: Option byte key
The following values must be programmed consecutively to unlock the FLASH_OPTCR
register and allow programming it:
77/1422
27
26
25
w
w
w
w
11
10
9
w
w
w
w
a)
KEY1 = 0x45670123
b)
KEY2 = 0xCDEF89AB
27
26
25
w
w
w
w
11
10
9
w
w
w
w
a)
OPTKEY1 = 0x08192A3B
b)
OPTKEY2 = 0x4C5D6E7F
Doc ID 018909 Rev 4
24
23
22
21
KEY[31:16]
w
w
w
w
8
7
6
5
KEY[15:0]
w
w
w
w
24
23
22
21
OPTKEYR[31:16
w
w
w
w
8
7
6
OPTKEYR[15:0]
w
w
w
w
20
19
18
w
w
w
4
3
2
w
w
w
20
19
18
w
w
w
5
4
3
2
w
w
w
RM0090
17
16
w
w
1
0
w
w
17
16
w
w
1
0
w
w
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