STM32L1 RDP Level1

Level 1: memory read protection enabled

This is the default read protection level after option byte erase. Read protection Level 1 is activated by writing any value (except for 0xAA and 0xCC used to set Level 0 and level 2, respectively) to the RDP option byte. When read protection Level 1 is set:

– No Flash memory module access (read, erase, program) is performed while the debug features are connected or boot from RAM or system memory is selected. A bus error (Cortex®-M3 hardfault or Busfault) is generated in case of a Flash memory read request. All operations are possible when Flash user boot is used.

– Programming the protection option byte to lower protection causes the Flash memory module and the backup registers (in RTC) to be mass-erased. That is, the user code contents are cleared before the read protection is removed.

* en.CD00240193(RM0038-ReferenceManual).pdf

* en.STM32L4_System_Memory_Protections.pdf