Mechatronics Engineering Lecture 10 - Microcontrollers

Mechatronics Engineering (OFRME200) Lecture 10

• Course Level: 2, Fall Semester
• Instructor: Walaa Shoeib
• University: Menoufia University, Faculty of Electronic Engineering

Chapter 5: Microcontroller Structure

• This chapter focuses on the structure of microcontrollers.

Registers

• Instruction Register (IR): Stores an instruction after fetching it from memory. CPU stores the instruction into the IR. Decoding and execution of the operation follows.
• Program Counter (PC): A special register keeping track of the memory address of the next instruction to be executed in a program.
• Memory Unit: Contains the program counter, instruction register, memory address register, and accumulator register.
• Control Unit (CU): Executes the instructions stored in the IR.
• Arithmetic and Logic Unit (ALU): Performs arithmetic and logical operations.
• Data Bus: Carries data between components.
• Address Bus: Carries the memory address to be accessed.
• Control Bus: Carries control signals to coordinate operations between components.

Memory

• Memory Unit: Stores binary data. Data can be program instruction codes or numbers to be operated on.
• Memory Size: Determined by the number of wires in the address bus.
• Memory Element: A unit consisting of many storage cells. Each cell can store a 0 or a 1 bit.
• Memory Locations: Cells grouped into locations; each storing one word.
• Address: Unique identifier for each location used to access the stored word.

Types of Memory

• ROM (Read-Only Memory): Permanent storage for data programmed during manufacturing. Data cannot be written to it.
• PROM (Programmable ROM): Can be programmed once, but cannot be erased.
• EPROM (Erasable Programmable ROM): Programmable and erasable, erased by UV light.
• EEPROM (Electrically Erasable Programmable ROM): Programmed and erased electrically.
• RAM (Random-Access Memory): Temporary storage for data currently being operated on. Data can be readily read and written.

Read-Only Memory (ROM)

• ROM stores data permanently.
• ROMs are pre-programmed at manufacturing.
• Data can only be read from a ROM.

Erasable and Programmable ROM (EPROM)

• EPROM is programmable and erasable.
• Patterns can be altered.
• Erasure is accomplished by shining UV light on the device.

Electrically Enable PROM (EEPROM)

• EEPROM is similar to EPROM.
• Erasure is achieved by applying high voltage instead of UV light.

Random-Access Memory (RAM)

• RAM stores temporary data for processes.
• It can store and retrieve data very quickly.

Open Loop Control System

• Output depends solely on the input, without feedback.
• Control device directly affects the actuator.
• No feedback loop.
• Simple and cost-effective; however, cannot adjust the output.

Closed Loop Control System

• Also called feedback control system.
• Incorporates an input, a forward path, and a feedback path, enabling feedback.
• Detects actual output and adjusts it.

Component of Mechatronics System

• Actuators: (e.g., solenoids, DC motors, stepper motors, servo motors, hydraulics, pneumatics.)
• Mechanics and Energy Converter: (e.g., mechanical, hydraulic, thermal, electrical)
• Sensors: (e.g., switches, potentiometers, photoelectric sensors, digital encoders, strain gauges, thermocouples, accelerometers, MEMS)
• Input Signal Conditioning and Interfacing: (e.g., discrete circuits, amplifiers, filters, analog-to-digital (A/D) and digital-to-analog (D/A) converters)
• Output Signal Conditioning and Interfacing: (e.g., amplifiers, D/A converters, PWM, power op amps)
• Graphical Displays: (e.g., LEDs, digital displays, LCDs, CRTs)
• Digital Control Architectures: (e.g., logic circuits, microcontrollers, PLCs, sequencing and timing, logic and arithmetic control algorithms, communication)

This quiz covers the structure of microcontrollers as discussed in Chapter 5 of the Mechatronics Engineering course. Key components such as the instruction register, program counter, and control unit are examined. Perfect for those looking to reinforce their understanding of microcontroller architecture.