Embedded Flash memory interface
RM0090
DocID018909 Rev 11
3.9.3
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
3.9.4
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
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KEY[31:16]
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KEY[15:0]
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Bits 31:0
FKEYR[31:0]
: FPEC key
The following values must be programmed consecutively to unlock the FLASH_CR register
and allow programming/erasing it:
a) KEY1
=
0x45670123
b) KEY2
=
0xCDEF89AB
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OPTKEYR[31:16
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OPTKEYR[15:0]
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Bits 31:0
OPTKEYR[31:0]
: Option byte key
The following values must be programmed consecutively to unlock the FLASH_OPTCR
register and allow programming it:
a)
OPTKEY1 = 0x08192A3B
b)
OPTKEY2 = 0x4C5D6E7F