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Microcontrollers and Microprocessors in UET 102 Module 4

Module 4 Introduction

  • Welcome to Module 4 of UET 102.

  • Topic: Microcontrollers and their role in electronic circuits.

  • Key goals for this lesson:

    • Understanding Arduino technology.

    • Explaining how microcontrollers function.

    • Identifying practical applications of microcontrollers.

    • Differentiating between analog and digital inputs.

    • Learning the fundamentals of programming Arduino.

  • Structure of Module 4:

    • Lesson 1: Microcontrollers

    • Lesson 2: Microprocessors

    • Lesson 3: Hands-on Practice with Microcontroller Basics

    • Introduction of Microcontroller Board and Architecture (GPIOs and Basic RAM)

    • Getting Started with Arduino

    • Digital and Analog Inputs and Outputs

    • Arduino Programming Basics

Lesson 1: Introduction to a Microcontroller

  • A microcontroller is a compact integrated circuit designed to govern a specific operation in an embedded system.

  • Common microcontroller boards include Arduino and Raspberry Pi.

  • For practical understanding, it is encouraged to have an Arduino board available while studying this module.

Lesson 2: Introduction of a Microcontroller Board and Its Architecture

  • Architecture of a Microcontroller:

    • Contains multiple CPUs (processor cores), memory, and programmable input/output peripherals.

    • Does not require additional components like a GPU for operation.

Microcontroller Specifications:

  1. Storage:

    • Measured in kilobytes (KB), where 1 KB = 1,000 bytes.

    • Example: Minimum storage of 8 KB can hold 8,000 bytes of command code, equating to letters and spaces included in commands.

  2. Processing Power:

    • Represented in bits; functions as the brain of the device.

    • Responsible for processing commands and controlling microcontroller operations involving arithmetic and logical functions.

    • Communicates with other components in an embedded system (Massimo, Shiloh, 2015).

  3. Input/Output (I/O) Peripherals:

    • Interface for connecting to the outside world through input ports and output devices.

    • Input ports receive binary data from external information; the processor sends commands to output devices.

Core Components of a Microcontroller

  • Visibility: Core components are invisible without specialized X-ray machines.

  • Casing and GPIOs: Only visible parts are casing and general-purpose GPIOs.

Key Components:

  1. DAC (Digital-to-Analog Converter):

    • Converts digital signals to continuous analog signals (e.g., controlling motors, generating audio).

  2. I/O Pins:

    • Pins for interfacing with sensors and devices; configured as inputs or outputs depending on use.

    • The number of available I/O pins varies by model.

  3. ROM (Read-Only Memory):

    • Stores permanent, unalterable data and instructions for device functioning (e.g., boot-up routines). Non-volatile and retains information when powered off.

  4. CPU (Central Processing Unit):

    • Executes instructions, performs calculations, and manages input/output operations specific to embedded systems.

  5. RAM (Random Access Memory):

    • Temporary data storage; limited in microcontrollers compared to larger computing devices. Important for program execution space.

  6. Clock:

    • Generates a synchronized signal for operations, affecting processing speed and power consumption (measured in Hertz). Higher frequency means faster operations but increased power consumption.

  7. ADC (Analog-to-Digital Converter):

    • Converts analog signals to digital values for processing.

    • Resolution impacts accuracy; an 8-bit ADC can represent 256 values.

  8. GPIO Pins:

    • Input/Output interface for external component interactions.

Microcontroller Sizes and Specifications

  • Not singular in type; increased complexity affects specifications.

  • Typical operating voltage: 1.8V—3.8V, requiring resistors and capacitors to regulate voltage levels.

Applications:

  • Found in devices such as microwaves, ovens, TVs, robotics, etc.

  • Microcontrollers utilize flash memory for programming and operation.

Architecture Types:

  • Example: AVR microcontroller with Harvard architecture enables simultaneous data access, improving efficiency (Ju & Gurvich, 2007).

Microcontroller Functioning

  • Control set stores instructions and directs the CPU and RAM for output through I/O pins in the circuit.

  • Illustrative metaphor: AVR architecture likened to a library with separate collections for instructions and data, enhancing efficiency in executing commands.

Getting Started with Arduino

  • Arduino is an open-source platform designed for creating interactive physical objects.

  • Ideal for beginners with minimal technical expertise.

  • Key components of typical Arduino boards:

    1. Microcontroller (brain of the Arduino): Executes loaded programs.

    2. USB port: Connects Arduino to a computer for programming.

    3. USB to Serial Chip: Facilitates data translation from computer to microcontroller.

    4. Digital Pins: Operate as digital logic switches.

    5. Analog Pins: Read analog values (10-bit resolution).

    6. Power Pins: 5V / 3.3V for powering devices.

    7. Ground (GND): Completes a circuit; represents 0 volts.

    8. VIN: Connection for external power supplies.

Arduino Programming Basics

  • Arduino uses a simplified version of C/C++ for programming, utilizing an Integrated Development Environment (IDE) for coding, uploading, and testing.

  • Each Arduino sketch contains two functions:

    1. setup(): Initializes settings once at the start.

    2. loop(): Repeats execution continuously until power is off.

Example Sketch Structure:

  • Code typically includes variable declarations, functions, and libraries at the beginning, followed by setup and loop definitions.