ST STM32F405 User Manual

Embedded Flash memory interface RM0090
96/1749 RM0090 Rev 18
When a sector is readout protected (PCROP mode activated), it can only be accessed for
code fetch through ICODE Bus on Flash interface:
• Any read access performed through the D-bus triggers a RDERR flag error.
• Any program/erase operation on a PCROPed sector triggers a WRPERR flag error.
Figure 7. PCROP levels
The deactivation of the SPRMOD and/or the unprotection of PCROPed user sectors can
only occur when, at the same time, the RDP level changes from 1 to 0. If this condition is not
respected, the user option byte modification is cancelled and the write error WRPERR flag
is set. The modification of the users option bytes (BOR_LEV, RST_STDBY, ..) is allowed
since none of the active nWRPi bits is reset and SPRMOD is kept active.
Note: The active value of nWRPi bits is inverted when PCROP mode is active (SPRMOD =1).
If SPRMOD = 1 and nWRPi =1, then user sector i of bank 1, respectively bank 2 is
read/write protected (PCROP).
Level 1
Level 2
RDP = 0xCC
RDP /= 0xAA
RDP /= 0xCC
default
User option sector erase
Program new options
Global mass erase
User option section erase
Program new options
Write options
SPMOD = active
and valid nWRPi*
No restriction on
Write options
Write options
SPMOD = active
and valid nWRPi*
Level 0
RDP = 0xAA
Write options
SPMOD = active
and valid nWRPi*
Write options
SPMOD = active
and valid nWRPi*
Write options
SPMOD = active
and valid nWRPi*
* Valid nWRPi means that none of the nWRP bits set can be reset (transition from 1 to 0)
MS30467V1

ST STM32F405 Specifications

General

Brand	ST
Model	STM32F405
Category	Computer Hardware
Language	English