1.RIG-NITC WORKSHOP ON BASIC ROBOTICS AND EMBEDDED SYSTEMS SIMULATION

2. Doubts? You are free to ask your doubts!! 3. Microcontrollers abbreviated C, uC or MCU single integrated circuit processor core memory programmable input/output peripherals. A computer system optimized for hardware control in a single piece of silicon.. 4. See what a uC can do.!! 5. Microcontrollers Most popular microcontrollers. AVR ARM PIC 8051 E.g. AVR ATmega8,ATmega16,Cortex A8,A10 6. Atmega 16 7. 8-bit high performance uC 1 MIPS speed at 1 MHz 16 Kb FLASH Memory Static RAM of 1 Kb 0.5 Kb EEPROM 40 PIN design 32 I/O ports. 3 timers SPI, TWI, serial interfacing ADC converters Internal 1 MHz oscillator 8. Extra Information: General purpose register : Stores local variables I/O registers: Configures the I/O peripherals FLASH: Stores our program code and bootloader Starts with memory address 0x00 EEPROM: It can be used to store those values to be stored even when switched off Slow to access 9. I/O ports 4 i/o ports namely PORT A, PORT B, PORT C and PORT D PORT A has ADC Any PIN can be configured both for input or output. BUT how to configure?? 10. AVR REGISTERS Stores some important values Windows registry..? Contains address of pins in hexadecimal values Stores the configuration settings 11. Registers Data Direction Register(DDR) 0 means INPUT PIN 1 means OUTPUT PIN PORT Register Configures output 0 means 0v 1 means 5v PIN register Stores the input at any PIN 1if input is a 5v signal 0 if input is 0v 12. Binary to HexaDecimal Conversion Easy to express. Binary contains 0 and 1 Hexadecimal s/m contain 0 to 9 and A to F Binary to hex Hex to binary 13. Use of TTL logic.? What is TTL logic 0s and 1s what is its meaning?? 0GND.but what is GND 1VCCwhat is VCC 14. DDR DDRx where x=A,B,C,D 8-BIT binary/hexadecimal value Example: DDRA=0B01110101; 15. PORT To configure the output settings 8-BIT binary/hexadecimal value 16. PULL UP RESISTOR Reduce noise..what is noise?? PORTx bits set 1ut DDRx is set 0 Resistor comes in series. 17. Input monitoring?? Have you ever thought.? How? 18. PIN Stores the input that the microcontroller detects Example of input s/m 8-bit binary/hexadecimal value Example: If PINA==0b00101111do something 19. But how to write the code?? 20. Embedded C Most powerful programming Language Fast execution Reduced Instructions Similar to simple C coding 21. Essential Software and Hardware Softwares:(will be provided: open source) Winavr HIDbootFlash Proteus ISIS Hardwares:(will be provided) RigDev Board Low cost than corporate development boards Based on Atmega 16 In built USB interfacing 22. Getting Started Install Winavr Install HIDbootFlash Check the RigDev Board Programmers notepad mfile 23. General Structure of a code #include int main() { } This is the general format of any embedded C code that we write for ATmega uCs. #include includes the details about the PIN configurations of ATmega series of uCs. Our code is written inside the main() function. 24. Programmers Notepad 25. Programmers Notepad Save code as main.c Create makefile Tools make all 26. Makefile Written in mfile Change mcu name Change frequency 27. Lets do something LED Lighting CathodeGND ANODE5v 28. More about it Made up mostly using GaAs. Light emitted due to electrical excitation How to identify cathode Leg method Edge method NEVER CONNECT LED DIRECTLY TO SUPPLY Resistor in series. 29. Lets Do Something LED Blinking #include _delay_ms(); _delay_us(); #include #include main() { DDRA=0X01; While(1) { PORTA=0X01; _delay_ms(1000); PORTA=0X00; _delay_ms(1000); } } 30. Pulse Width Modulation(PWM) What is a PWM signal. DAC 31. Duty Cycle How is it usefull.?? 32. DAC examples LED contrast control RMS voltage is exploited 33. LED Contrast Control #include pwm.h includes the header file for speed control pwminit(int freq) initializes pwm at required frequency pwm(int a,int b) sets pwm on PD4 and PD5 a and b are duty cycles a controls PD4 and b controls PD5 34. coding #include #include #include pwm.h int main() { While(1) { DDRB=0x30; pwminit(50); pwm(0,50); _delay_ms(2000); pwm(50,0); _delay_ms(2000); pwm(100,100); _delay_ms(2000); } } 35. Motor Speed Control #include pwm.h includes the header file for speed control pwminit(int freq) initializes pwm at required frequency pwm(int a,int b) sets pwm on PD4 and PD5 a and b are duty cycles a controls PD4 and b controls PD5 36. Motor speed control #include #include #include pwm.h int main() { While(1) { DDRB=0x30; pwminit(50); pwm(0,50); _delay_ms(2000); pwm(50,0); _delay_ms(2000); pwm(100,100); _delay_ms(2000); } } 37. Have fun..!!