ATMEGA8A-PU Atmel, ATMEGA8A-PU Datasheet - Page 226

• Manufacturer Part Number: ATMEGA8A-PU
• Description: MCU AVR 8K FLASH 16MHZ 28-PDIP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA8A-PU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• 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 6x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-DIP (0.300", 7.62mm)
• Processor Series: ATMEGA8x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 1 KB
• Interface Type: SPI, TWI, USART
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 23
• Number Of Timers: 3
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 6 Channel
• Package: 28PDIP
• Device Core: AVR
• Family Name: ATmega
• Maximum Speed: 16 MHz
• Operating Supply Voltage: 3.3|5 V
• Controller Family/series: AVR MEGA
• No. Of I/o's: 23
• Eeprom Memory Size: 512Byte
• Ram Memory Size: 1KB
• Cpu Speed: 16MHz
• Rohs Compliant: Yes
• For Use With: ATSTK600 - DEV KIT FOR AVR/AVR32ATSTK500 - PROGRAMMER AVR STARTER KIT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

24. Memory Programming
24.1
8159D–AVR–02/11
Program And Data Memory Lock Bits
The ATmega8A provides six Lock Bits which can be left unprogrammed (“1”) or can be pro-
grammed (“0”) to obtain the additional features listed in
erased to “1” with the Chip Erase command.
Table 24-1.
Note:
Table 24-2.
BLB12
BLB11
BLB02
BLB01
LB2
LB1
BLB0 Mode
LB Mode
Lock Bit Byte
1
2
3
1
2
3
4
1. “1” means unprogrammed, “0” means programmed
Memory Lock Bits
Lock Bit Byte
Lock Bit Protection Modes
BLB02
LB2
1
1
0
1
1
0
0
BLB01
LB1
Bit No.
1
0
0
1
0
0
1
7
6
5
4
3
2
1
0
Protection Type
No memory lock features enabled.
Further programming of the Flash and EEPROM is disabled in
Parallel and Serial Programming mode. The Fuse Bits are
locked in both Serial and Parallel Programming mode.
Further programming and verification of the Flash and
EEPROM is disabled in parallel and Serial Programming mode.
The Fuse Bits are locked in both Serial and Parallel
Programming modes.
No restrictions for SPM or LPM accessing the Application
section.
SPM is not allowed to write to the Application section.
SPM is not allowed to write to the Application section, and LPM
executing from the Boot Loader section is not allowed to read
from the Application section. If Interrupt Vectors are placed in
the Boot Loader section, interrupts are disabled while executing
from the Application section.
LPM executing from the Boot Loader section is not allowed to
read from the Application section. If Interrupt Vectors are placed
in the Boot Loader section, interrupts are disabled while
executing from the Application section.
(2)
Description
–
–
Boot lock bit
Boot lock bit
Boot lock bit
Boot lock bit
Lock bit
Lock bit
(1)
Table
24-2. The Lock Bits can only be
Default Value
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
ATmega8A
(1)
(1)
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