Atmel AVR XMEGA AU series User Manual

36
8331B–AVR–03/12
Atmel AVR XMEGA AU
• Bit 3:2 – BLBAT[1:0]: Boot Lock Bit Application Table Section
These lock bits control the software security level for accessing the application table section for
software access. The BLBAT bits can only be written to a more strict locking. Resetting the
BLBAT bits is possible by executing a chip erase command.
• Bit 1:0 – LB[1:0]: Lock Bits
(1)
These lock bits control the the security level for the flash and EEPROM during external program-
ming. These bits are writable only through an external programming interface. Resetting the lock
Table 4-10. 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 the application
section.
01 RLOCK
Read lock – (E)LPM executing from the boot loader
section is not allowed to read from the application
section.
If the interrupt vectors are placed in the boot loader
section, interrupts are disabled while executing from the
application section.
00 RWLOCK
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
application section.
If the interrupt vectors are placed in the boot loader
section, interrupts are disabled while executing from the
application section.
Table 4-11. Boot lock bit for the application table section.
BLBAT[1:0] Group Configuration Description
11 NOLOCK
No lock – no restrictions for SPM and (E)LPM accessing
the application table section.
10 WLOCK
Write lock – SPM is not allowed to write the application
table
01 RLOCK
Read lock – (E)LPM executing from the boot loader
section is not allowed to read from the application table
section.
If the interrupt vectors are placed in the boot loader
section, interrupts are disabled while executing from the
application section.
00 RWLOCK
Read and write lock – SPM is not allowed to write to the
application table section, and (E)LPM executing from
the boot loader section is not allowed to read from the
application table section.
If the interrupt vectors are placed in the boot loader
section, interrupts are disabled while executing from the
application section.

Atmel AVR XMEGA AU series Specifications

General

Brand	Atmel
Model	AVR XMEGA AU series
Category	Microcontrollers
Language	English