ATMEGA8U2_1 ATMEL [ATMEL Corporation], ATMEGA8U2_1 Datasheet - Page 3

• Manufacturer Part Number: ATMEGA8U2_1
• Description: 8-bit Microcontroller with 8/16/32K Bytes of ISP Flash and USB Controller
• Manufacturer: ATMEL [ATMEL Corporation]

2. Overview
The ATmega8U2/16U2/32U2 is a low-power CMOS 8-bit microcontroller based on the AVR enhanced RISC architecture.
By executing powerful instructions in a single clock cycle, the ATmega8U2/16U2/32U2 achieves throughputs approaching
1 MIPS per MHz allowing the system designer to optimize power consumption versus processing speed.
2.1
Figure 2-1.
7799CS–AVR–12/09
GND
VCC
Block Diagram
ON-CHIP DEBUG
PROGRAMMING
Debug-Wire
LOGIC
Block Diagram
DATA REGISTER
USART1
PORTD
PORTD DRIVERS
PD7 - PD0
The AVR core combines a rich instruction set with 32 general purpose working registers. All the
32 registers are directly connected to the Arithmetic Logic Unit (ALU), allowing two independent
registers to be accessed in one single instruction executed in one clock cycle. The resulting
INSTRUCTION
INSTRUCTION
PROGRAM
PROGRAM
REGISTER
COUNTER
CONTROL
DECODER
FLASH
LINES
REG. PORTD
DATA DIR.
SPI
POR - BOD
REGISTERS
REGISTER
PURPOSE
GENERAL
POINTER
STATUS
STACK
RESET
SRAM
DATA REGISTER
ALU
X
Y
Z
PORTC
PORTC DRIVERS
PC7 - PC0
REG. PORTC
DATA DIR.
MCU CONTROL
OSCILLATOR
WATCHDOG
INTERRUPT
COUNTERS
REGISTER
INTERNAL
EEPROM
TIMER/
TIMER
UNIT
8-BIT DA TA BUS
DATA REGISTER
PORTB
OSCILLATOR
ATmega8U2/16U2/32U2
TIMING AND
CALIB. OSC
CONTROL
PORTB DRIVERS
PLL
USB
PS/2
PB7 - PB0
REG. PORTB
DATA DIR.
REGULATOR
ON-CHIP
3.3V
UVcc
D+/SCK
D-/SDATA
1uF
UCap
3