ATMEGA649A-AU Atmel, ATMEGA649A-AU Datasheet - Page 298

• Manufacturer Part Number: ATMEGA649A-AU
• Description: IC MCU AVR 64K FLASH 64TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA649A-AU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: SPI, UART/USART, USI
• Peripherals: Brown-out Detect/Reset, LCD, POR, PWM, WDT
• Number Of I /o: 54
• Program Memory Size: 64KB (32K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 2K x 8
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TQFP
• Processor Series: ATmega
• Core: AVR
• Data Bus Width: 8 bit
• Data Ram Size: 4 KB
• Interface Type: SPI, USART
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 54
• Number Of Timers: 3
• Operating Supply Voltage: 3.3 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Operating Temperature Range: - 40 C to + 85 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

26.5
8284A–AVR–10/10
Boot Loader Lock Bits
Figure 26-2. 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
Lock bits 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 con-
trol the programming 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.
ATmega169A/169PA/329A/329PA/649A/649P/3290A/3290PA/6490A/6490P
Table 26-2
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'
and
BOOTSZ = '01'
Table 26-3 on page 299
0x0000
End RWW
Start NRWW
End Application
Start Boot Loader
Flashend
0x0000
End RWW
Start NRWW
End Application
Start Boot Loader
Flashend
for further details. The Boot Lock bits and general
Boot Loader Flash Section
Boot Loader Flash Section
Application Flash Section
Application Flash Section
Application Flash Section
Table 26-9 on page
Program Memory
Program Memory
BOOTSZ = '10'
BOOTSZ = '00'
307.
0x0000
End RWW
Start NRWW
End Application
Start Boot Loader
Flashend
0x0000
End RWW, End Application
Start NRWW, Start Boot Loader
Flashend
298