XMEGAA_09 Datasheet, PDF (34/445 Pages) ATMEL Corporation – Interrupts and Programmable Multi-level Interrupt Controller

XMEGA A
Table 4-8. Boot Lock Bit for The Boot Loader Section
BLBB[1:0]
Group Configuration Description
11
NOLOCK
No Lock, no restrictions for SPM and (E)LPM accessing
the Boot Loader section.
10
WLOCK
Write Lock, SPM is not allowed to write the Boot Loader
section
Read Lock, (E)LPM executing from the Application
section is not allowed to read from the Boot Loader
section.
01
RLOCK
If the interrupt vectors are placed in the Application
section, interrupts are disabled while executing from the
Boot Loader section.
Read and Write Lock, SPM is not allowed to write to the
Boot Loader section and (E)LPM executing from the
Application section is not allowed to read from the Boot
00
RWLOCK
Loader section.
If the interrupt vectors are placed in the Application
section, interrupts are disabled while executing from the
Boot Loader section
• Bit 5:4 - BLBA[1:0]: Boot Lock Bit Application Section
These bits indicate the locking mode for the Application Section. Even though the BLBA bits are
writable, they can only be written to a stricter locking. Resetting the BLBA bits is only possible by
executing a Chip Erase Command.
Table 4-9. Boot Lock Bit for the Application Section
BLBA[1:0]
Group Configuration Description
11
NOLOCK
No Lock, no restrictions for SPM and (E)LPM accessing
the Application Section.
10
WLOCK
Write Lock, SPM is not allowed to write them
Application Section
Read Lock, (E)LPM executing from the Boot Loader
Section is not allowed to read from the Application
Section.
01
RLOCK
If the interrupt vectors are placed in the Boot Loader
Section, interrupts are disabled while executing from the
Application Section.
Read and Write Lock, SPM is not allowed to write to the
Application Section and (E)LPM executing from the
Boot Loader Section is not allowed to read from the
00
RWLOCK
Application section.
If the interrupt vectors are placed in the Boot Loader
Section, interrupts are disabled while executing from the
Application Section.
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