The document discusses microcontrollers from the AVR family made by Atmel, specifically the ATmega8. It provides details on the ATmega8's features such as its 8-bit RISC architecture, 8KB of flash memory, timers, PWM channels, ADC, and communication interfaces. It also introduces software tools for programming AVR microcontrollers like WinAVR and libraries like AVRlib. Code examples are given for configuring PWM motor control, reading the ADC, and serial communication via UART.

1. 31 st Jan to 1 st Feb 2008 TECHNOLOGY ROBOTICS SOCIETY Indian Institute of Technology, Kharagpur

2. AVR Family of Microcontrollers 8-bit RISC Architecture, single cycle instructions Principle features include Internal oscillators, timers, UART, SPI, PWM generation, ADC, analog comparator and more… Amenability to C programming In-System-Programmable (ISP) Flash Memory http://www.atmel.com/products/AVR/

3. ATmega8 – AVR Family Member Up to 16 MIPS throughput 8KB ISP Flash Memory, 1KB SRAM, 512Byte EEPROM 8bit / 16bit timers / counters Three PWM channels 8 Channel 10 bit ADC, Analog Comparator Programmable UART, SPI, TWI

4. ATmega8 – PDIP Package

5. ATmega8 – TQFP Package

6. ISP Flash Memory ISP : In-System-Programmable Flash ROM No need of specialized programmer hardware No need to remove processor from circuit for reprogramming

7. STK200 ISP Dongle PonyProg Programming Software http://www.lancos.com/prog.html

8. WinAVR WinAVR is a open source software development suite for Atmel AVR series of RISC microcontrollers GUI Integrated Development Environment Includes the GNU GCC compiler for C and C++. http://winavr.sourceforge.net/

9. WinAVR IDE Screenshot

10. Procyon AVRlib AVRlib is a library of easy-to-use C functions for AVR controllers AVRlib aims to allow programmers to work quickly towards their end goal by reducing the time needed to write basic support functions and code http://www.procyonengineering.com/avr/avrlib/

11. PWM DC Motor Control //Dual 8-bit PWM mode setup of timer 1 timer1PWMInit (8); // Frequency Prescaling to F_CPU_CLOCK / 256 timer1SetPrescaler (4); // Left and right motor speed set timer1PWMASet (lSpeed); // Pin 15 (OC1A) timer1PWMBSet (rSpeed); // Pin 16 (OC1B) // Start on the PWM generation timer1PWMAOn (); timer1PWMBOn ();

12. ADC’s & Analog Comparator DDRA = 0x00; // Configure Port A (ADC) as Input PORTA = 0x00;// Disable internal pull up resistors // Initialize Analog to Digital Converter a2dInit(); // Set conversion speed a2dSetPrescaler(ADC_PRESCALE_DIV32); // Set analog voltage reference a2dSetReference(ADC_REFERENCE_AVCC); // Acquire analog data into digital format for (i = 0; i < 8; i ++) adcData [i] = a2dConvert8bit(i);

13. UART - Serial Communication // Initialize UART at 2400 bps uartInit(); uartSetBaudRate (2400); // Check is data received if (!uartReceiveBufferIsEmpty ()) { // if data received then get it in a variable uartReceiveByte (&dataIn); // do whatever u wish with dataIn }

14. Crystal Oscillator Clock Source

15. AVR Fuse settings SUT 1:0 = 11 12 – 22 pf >= 1.0 1011, 1101, 1111 0 12 – 22 pf 3.0 – 8.0 1111 1 12 – 22 pf 0.9 – 3.0 1101 1 - 0.4 – 0.9 1010 1 C1 & C2 Frequency (MHz) CKSEL3:0 CKOPT