ATMEGA8U2-AU Atmel, ATMEGA8U2-AU Datasheet - Page 257

• Manufacturer Part Number: ATMEGA8U2-AU
• Description: MCU AVR 8K FLASH 16MHZ 32TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA8U2-AU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: SPI, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 22
• Program Memory Size: 8KB (4K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-TQFP, 32-VQFP
• Processor Series: ATmega
• Core: AVR
• Data Bus Width: 8 bit
• Data Ram Size: 512 B
• Interface Type: SPI, USART, USB
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 22
• Number Of Timers: 2
• Operating Supply Voltage: 5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT, AT90USBKEY, ATEVK525
• Minimum Operating Temperature: - 40 C
• Operating Temperature Range: - 40 C to + 85 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Data Converters: -
• Lead Free Status / Rohs Status: Details

25.7.9
25.7.10
25.7.11
7799D–AVR–11/10
Programming the Fuse High Bits
Programming the Extended Fuse Bits
Programming the Lock Bits
The algorithm for programming the Fuse High bits is as follows (refer to
Flash” on page 253
The algorithm for programming the Extended Fuse bits is as follows (refer to
Flash” on page 253
Figure 25-5. Programming the FUSES Waveforms
The algorithm for programming the Lock bits is as follows (refer to
page 253
The Lock bits can only be cleared by executing Chip Erase.
1. A: Load Command “0100 0000”.
2. C: Load Data Low Byte. Bit n = “0” programs and bit n = “1” erases the Fuse bit.
3. Set BS2, BS1 to “01”. This selects high data byte.
4. Give WR a negative pulse and wait for RDY/BSY to go high.
5. Set BS2, BS1 to “00”. This selects low data byte.
1. 1. A: Load Command “0100 0000”.
2. 2. C: Load Data Low Byte. Bit n = “0” programs and bit n = “1” erases the Fuse bit.
3. 3. Set BS2, BS1 to “10”. This selects extended data byte.
4. 4. Give WR a negative pulse and wait for RDY/BSY to go high.
5. 5. Set BS2, BS1 to “00”. This selects low data byte.
1. A: Load Command “0010 0000”.
2. C: Load Data Low Byte. Bit n = “0” programs the Lock bit. If LB mode 3 is programmed
3. Give WR a negative pulse and wait for RDY/BSY to go high.
RESET +12V
(LB1 and LB2 is programmed), it is not possible to program the Boot Lock bits by any
External Programming mode.
RDY/BSY
PAGEL
XTAL1
DATA
for details on Command and Data loading):
XA1
XA0
BS1
BS2
WR
OE
0x40
A
for details on Command and Data loading):
for details on Command and Data loading):
DATA
C
Write Fuse Low byte
XX
0x40
A
DATA
C
ATmega8U2/16U2/32U2
Write Fuse high byte
XX
“Programming the Flash” on
0x40
A
DATA
C
Write Extended Fuse byte
“Programming the
“Programming the
XX
257