Breaking and stepping into code
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Thus, any attempt to load, or connect to, an application running from Flash crashes.
It is still possible to load, execute and debug an application in SRAM.
Option Bytes management can be done with ST-LINK utility or with an application
running from SRAM.
Going back to RDP Level 0 completely erases the Flash.
•
Level 2: No Debug.
JTAG/SWD connection is killed. There is no way back. In this case, nobody - even
STMicroelectronics - can perform any analysis of defective parts.
•
Level 0.5 is an additional protection level associated with TrustZone(only available in
STM32L5 Serie). RDP 0.5 is available only when TrustZone is enabled. Debug of
secure domain is forbidden, only non-secure domain can be accessed for debug.
Regression from level 0.5 to level 0 triggers a Flash mass erase, as well as backup
registers and all SRAMs.Regression from RDP Level 1 to RDP Level 0.5 leads to a
partial Flash memory erase: only the non-secure part is erased
Note:
Refer to AN5421 and AN5347 for more informations about Trustzone development on
STM32L5 Series.
5.3.2 PCROP
Proprietary Code ReadOut Protection is the ability to define secure area in Flash where user
can locate a proprietary code.
This prevents malicious software or debugger from reading sensitive code.
In case an application with third party code in PCROP area needs to be debugged, the
following points must be considered:
•
Step-into PCROP function is tolerated but ignored (Step-over)
•
Access to protected memory through debugger trigs Flash Interruption (Instrument
NMIHandler) and return default pattern for the whole area
For further details refer to section
Memory Protection
in the reference manual of the device.
Table 4. STM32 Series RDP protection extension
Product
RDP protection extension
F0
+ backup registers
F2
+ backup SRAM
F3
+ backup registers
F4
+ backup SRAM
L0
+ EEPROM
L1
+ EEPROM
L4
+ backup registers
+ SRAM2
L5
RDP 4 levels
+ backup reg SRAM2
F7
+ backup SRAM
H7
+ backup SRAM
Содержание STM32 Series
Страница 46: ...Connecting to the board AN4989 46 118 AN4989 Rev 3 Figure 30 Keil hotplug step2 ...
Страница 91: ...AN4989 Rev 3 91 118 AN4989 Debug through hardware exploration 117 Figure 69 STM32F4 F7 dual MCO capabilities ...
Страница 103: ...AN4989 Rev 3 103 118 AN4989 Managing DBGMCU registers 117 Figure 78 Generator Options debug MCU in STM32CubeIDE ...
