1. AVR ATMEGA 8 MICRO-CONTROLLER

2. INTRODUCTION
ATmega8 is a 8-bit microcontroller based on the AVR RISC architecture
By executing powerful instructions in a single clock cycle, the ATmega8 achieves throughput approaching 1 MIPS per MHz

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In order to maximize performance and parallelism, the AVR uses a Harvard architecture- which separates memories and buses for program and data
Instruction in program memory are executed with single level pipelining
This concept enables instructions to be executed in every clock cycle

4. Features High-performance 8 bit Microcontroller
Up to 16 MIPS Throughput at 16 MHz
32 x 8 General Purpose Working Registers
Six ADC channels in PDIP package
Internal Calibrated Oscillator

5. Types Of Packages 28-pin PDIP (Plastic Dual In-line Package)
32-pin TQFP (Thin Quad film Package)

6. Memory Segments 8K Bytes of Flash program memory
512 Bytes EEPROM (Electrically Erasable Programmable Read Only Memory)
1K Byte Internal RAM (Random Access Memory)

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Write/Erase Cycles: 10,000 Flash/100,000 EEPROM
Data retention: 20 years at 85°C/100 years at 25°C

8. Pin Out

9. Pin Description VCC Digital supply voltage GND Ground
RESET A low level on this pin for longer than the minimum pulse length will generate a reset, even if the clock is not running
AREF The analog reference pin for the A/D Converter

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AVCC The supply voltage pin for the A/D Converter

11. Ports Three ports i.e PortB, PortC, PortD
Three registers associated with every port
DDRx – Data Direction Register
PINx – Port input
PORTx- Port output
*Note – ‘x’ is subscript and could be either of B, C, D

12. Port B (PB7..PB0) Port B is an 8-bit bi-directional I/O port
Can be used either as a input port or as output port ( direction must be specified in programming)

13. Register Description Of I/O Ports

15. Port C (PC5..PC0) Port C is an 7-bit bi-directional I/O port
Can be used either as a input port or as output port ( direction must be specified in programming).

16. Port D (PD7..PD0) Port D is an 8-bit bi-directional I/O port
Can be used either as a input port or as output port ( direction must be specified in coding)

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21. Thank you…