AVR Microcontroller: Introduction & Components - PDF

AVR Microcontroller Embedded System Designing Dr. Shirin Saleh Ahari Department of Electrical and computer Engineering  Grading Mid-term exam: 30% Final exam: 40% laboratory: 30% References Muhammad Ali Mazidi, Sarmad Naimi, Sepehr Nai...

AVR Microcontroller Embedded System Designing Dr. Shirin Saleh Ahari Department of Electrical and computer Engineering  Grading Mid-term exam: 30% Final exam: 40% laboratory: 30% References Muhammad Ali Mazidi, Sarmad Naimi, Sepehr Naimi, “the AVR microcontroller and embedded system: using assembly and C” SYLLABUS OF MICROCONTROLLER COURSE  Introduction; application based introduction of microprocessors and microcontrollers, microcontroller vs microprocessor  The AVR microcontroller: history and features  AVR microcontroller Architecture.  C Review.  AVR programming and applications( mega 32/16) “According to the course flow”.  I/O Ports.  LCD  Timers/Counters  keypads  Analog to digital converter “A/D”.  Motor control with PWM  Introduction A microcontroller is a single chip, self contained computer.  Introduction Microprocessor vs. Microcontroller: the main difference is related to their operation and their Peripherals RAM ROM Serial & Micro- I/O Port Parallel Ports Processor Timer Interrupt  Introduction Microprocessor vs. Microcontroller Introduction  Microprocessor:  only processing of data  Faster  General purpose  Expensive  CPU is stand-alone, RAM, ROM, I/O, timer are separate.  Designer can control the amount of ROM, RAM and I/O ports.  It is cheaper compared to the microcontroller with the same features. Introduction  Microcontroller:  Slower.  Stand alone operation.  Cheaper.  CPU, RAM, ROM, I/O and timer are all on a single chip(but fixed amount).  Is used for applications in which cost, power and space are critical.  Single Operation. history AVR family  AVR family First AVR family AT90S series: These are the classic members of the AVR family and have fewer features than the next three, and less Word is used. ATtiny series: These microcontrollers are small in size 8 to 32 base and have better capabilities than the first category and are mostly used in systems that do not require a high port.it is 8 bit. ATmega Series: This category has more features than the previous two categories. These types of microcontrollers are self-programmable and can be programmed using additional circuits. It is 8 bit. It has 4–256 KB program memory. ATMEGA8, ATMEGA48, ATMEGA16, ATMEGA32,… Atxmega series: these category is the largest and the advanced one and has 16–384 KB program memory. It is 16 bit Fundamental Data Types microcontroller components  CPU  Memories  Input/output ports  Timer/counter  Parallel ports  Interrupt sources  PWM function  (A/D , D/A) converters microcontroller components  CPU: central proceeding unit  CPU is the brain of a microcontroller. CPU is responsible for fetching the instruction, decodes it, then finally executed. CPU connects every part of a microcontroller into a single system. The primary function of CPU is fetching and decoding instructions. The instruction fetched from program memory must be decoded by the CPU.  Flech  Decode  Execute  CPU components 1. Register 2. ALU: arithmetic logic unit (ALU) is a combinational digital circuit that performs arithmetic and bitwise operation 3. CU : control unit decodes the instructions, and controls all the other internal components of the CPU to make it work. An auxiliary register 1. Register: is a quickly accessible location available to a processor and is one of a small set of data holding places that may hold an instruction, a storage address, or any kind of data  Accumulator register: the accumulator is a register in which intermediate arithmetic and logic results are stored  Flag register: it is the status register, the value of these bits indicates some conditions that result after the execution of an instruction o Ex: ZF flag (zero falg): if the result of instruction will be zero then ZF=1 o Ex: sign flag (negative –positive statues):if the sign of the instruction will be negative then SF=1  Program counter or instruction pointer register: indicates where a CPU is in its program sequence and contains the address of the next instruction meaning that along executing the program a unity added to the line of number of the next instruction  Memory types:  There are several types of memory which is divided into RAM (random access memory) which is Volatile memory, and ROM (read-only memory)and Flash memory which are Non-Volatile  RAM  ROM  Flash memory  Memory types:  RAM(Random Access Memory): static and dynamic RAM ○ SRAM(Static RAM):  Very expensive  Very high performance  Constructed of Flip-Flops  RAM(Random Access Memory): ○ DRAM(Dynamic RAM):  Cheap  Constructed from Capacitors so it needs to be refreshed periodically.  It is divided into:  SDRAM(Synchronous DRAM) - SDR-SDRAM(Single Data Rate) - DDR-SDRAM(Double Data Rate) DDR-SDRAM has better performance and faster than the SDR- SDRAM and it is commonly used now in our computer  ROM(Read Only Memory): ROM(ROM) PROM(Programmable ROM). EPROM (Erasable PROM by UV light). EEPROM(Electrically Erasable PROM).  Flash Memory: ○ It is non-volatile computer memory that can be electrically erased and reprogrammed. It is a technology that is primarily used in memory cards and USB flash drives for general storage and transfer of data between computers and other digital products. It is a specific type of EEPROM (Electrically Erasable Programmable Read-Only Memory) that is erased and programmed in large blocks (it is faster than EEPROM)  I/O: Input/output ports  Parallel input/output ports are mainly used to drive/interface various devices such as LCD’S, LED’S, printers, memories, etc to a microcontroller