Downloaded 168 times
Uploaded byNitesh Singh
A tmega8 basics
The document provides an overview of the ATmega8 microcontroller, which is an 8-bit microcontroller based on the AVR RISC architecture. It can achieve throughput of up to 1 MIPS per MHz. The ATmega8 uses a Harvard architecture that separates program and data memories and buses. It has features such as 8K bytes of flash memory, 512 bytes of EEPROM, 1K byte of RAM, and three 8-bit I/O ports (Ports B, C, and D).
More Related Content
A tmega8 basics
- 1. AVR ATMEGA 8 MICRO-CONTROLLER
- 2. INTRODUCTION • ATmega8 isa 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
- 3. Contd.... • In orderto 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 • 8KBytes of Flash program memory • 512 Bytes EEPROM (Electrically Erasable Programmable Read Only Memory) • 1K Byte Internal RAM (Random Access Memory)
- 7. Contd.... • Write/Erase Cycles:10,000 Flash/100,000 EEPROM • Data retention: 20 years at 85°C/100 years at 25°C
- 8.
- 9. PIN DESCRIPTION • VCCDigital 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
- 10. Contd.... • AVCC Thesupply voltage pin for the A/D Converter
- 11. PORTS • Three portsi.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 OFI/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)
- 17.
- 18.
- 19.
- 20.
- 21.