ATMEGA644P-A15MZ Atmel, ATMEGA644P-A15MZ Datasheet - Page 282

• Manufacturer Part Number: ATMEGA644P-A15MZ
• Description: MCU AVR 64KB FLASH 16MHZ 44QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA644P-A15MZ

• Package / Case: 44-VQFN Exposed Pad
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Speed: 16MHz
• Number Of I /o: 32
• Eeprom Size: 2K x 8
• Core Processor: AVR
• Program Memory Type: FLASH
• Ram Size: 4K x 8
• Program Memory Size: 64KB (64K x 8)
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Connectivity: I²C, SPI, UART/USART
• Core Size: 8-Bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

24.5
282
Boot Loader Lock Bits
ATmega164P/324P/644P
Figure 24-2. 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:
• 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.
See
can be set in software and in 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 pro-
gramming of the Flash memory by SPM instruction. Similarly, the general Read/Write Lock
(Lock Bit mode 1) does not control reading nor writing by LPM/SPM, if it is attempted.
Table 24-2 on page 283
1. The parameters in the figure above are given in
Boot Loader Flash Section
Boot Loader Flash Section
Application Flash Section
Application Flash Section
Application Flash Section
Application Flash Section
Program Memory
Program Memory
BOOTSZ = '11'
BOOTSZ = '01'
and
0x0000
End RWW
Start NRWW
End Application
Start Boot Loader
Flashend
0x0000
End RWW
Start NRWW
End Application
Start Boot Loader
Flashend
Table 24-3 on page 283
Boot Loader Flash Section
Boot Loader Flash Section
Application Flash Section
Application Flash Section
Application Flash Section
Table 24-7 on page
Program Memory
Program Memory
BOOTSZ = '10'
BOOTSZ = '00'
for further details. The Boot Lock bits
291.
0x0000
End RWW
Start NRWW
End Application
Start Boot Loader
Flashend
0x0000
End RWW, End Application
Start NRWW, Start Boot Loader
Flashend
7674F–AVR–09/09