ATMEGA88-20MUR Atmel, ATMEGA88-20MUR Datasheet - Page 272

• Manufacturer Part Number: ATMEGA88-20MUR
• Description: MCU AVR 8K FLASH 20MHZ 32QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA88-20MUR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 23
• Program Memory Size: 8KB (4K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: *
• Cpu Family: ATmega
• Device Core: AVR
• Device Core Size: 8b
• Frequency (max): 20MHz
• Interface Type: SPI/TWI/USART
• Total Internal Ram Size: 1KB
• # I/os (max): 23
• Number Of Timers - General Purpose: 3
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• On-chip Adc: 8-chx10-bit
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 32
• Package Type: MLF EP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

27.5
2545T–AVR–05/11
Boot loader lock bits
Figure 27-2. 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 27-2 on page 273
1. The parameters in
Boot loader flash section
Application flash section
Application flash section
Boot loader flash section
Application flash section
Application flash section
Program memory
Program memory
BOOTSZ = '11'
BOOTSZ = '01'
Figure 27-2
and
0x0000
End RWW
Start NRWW
End application
Start boot loader
Flashend
0x0000
End RWW
Start NRWW
End application
Start boot loader
Flashend
Table 27-3 on page 273
are given in
Table 27-6 on page
Boot loader flash section
Application flash section
Application flash section
Boot loader flash section
Application flash section
Program memory
Program memory
BOOTSZ = '10'
BOOTSZ = '00'
for further details. The Boot Lock bits
ATmega48/88/168
281.
0x0000
End RWW
Start NRWW
End application
Start boot loader
Flashend
0x0000
End RWW, end application
Start NRWW, start boot loader
Flashend
272