ATMEGA8-16AI SL383 Atmel, ATMEGA8-16AI SL383 Datasheet - Page 211

• Manufacturer Part Number: ATMEGA8-16AI SL383
• Description: Semiconductors and Actives, Microprocessors, Microcontrollers
• Manufacturer: Atmel

Boot Loader Lock
Bits
2486W–AVR–02/10
Figure 102. Memory Sections
Note:
If no Boot Loader capability is needed, the entire Flash is available for application code. The
Boot Loader has two separate sets of Boot Lock Bits which can be set independently. This gives
the user a unique flexibility to select different levels of protection.
The user can select:
•
•
•
•
See
Serial or Parallel Programming mode, but they can be cleared by a chip erase command only.
The general Write Lock (Lock bit mode 2) does not control the programming of the Flash mem-
ory by SPM instruction. Similarly, the general Read/Write Lock (Lock bit mode 3) does not
control reading nor writing by LPM/SPM, if it is attempted.
To protect the entire Flash from a software update by the MCU.
To protect only the Boot Loader Flash section from a software update by the MCU.
To protect only the Application Flash section from a software update by the MCU.
Allow software update in the entire Flash.
Table 78
1. The parameters in the figure are given in
Boot Loader Flash Section
Boot Loader Flash Section
Application Flash Section
Application Flash Section
Application Flash Section
Application Flash Section
and
Program Memory
Program Memory
BOOTSZ = '11'
BOOTSZ = '01'
Table 79
for further details. The Boot Lock Bits can be set in software and in
(1)
$0000
End RWW
Start NRWW
End Application
Start Boot Loader
Flashend
$0000
End RWW
Start NRWW
End Application
Start Boot Loader
Flashend
Table 82 on page
Boot Loader Flash Section
Boot Loader Flash Section
Application Flash Section
Application Flash Section
Application flash Section
Program Memory
Program Memory
BOOTSZ = '10'
BOOTSZ = '00'
220.
ATmega8(L)
$0000
End RWW
Start NRWW
End Application
Start Boot Loader
Flashend
$0000
End RWW, End Application
Start NRWW, Start Boot Loader
Flashend
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