EC eight seven nine one - EMBEDDED AND REAL TIME SYSTEMS
EC eight seven nine one - EMBEDDED AND REAL TIME SYSTEMS
COMPLETE two-MARKS QUESTION BANK WITH ANSWERS
UNIT ONE: INTRODUCTION TO EMBEDDED SYSTEM DESIGN Complex Systems | Design Process | Model Train | QA | Consumer Electronics
Q one. What is an embedded system? Give two examples.
An embedded system is a computer system designed to perform a dedicated function within a larger mechanical or electrical system. It has fixed hardware and software optimized for specific tasks.
* Key: Dedicated function plus real-time constraints
Q two. Mention the challenges in embedded computing system design.
Key challenges: (one) Meeting real-time deadlines, (two) Limited memory and processing power, (three) Power/battery constraints, (four) Hardware-software co-design complexity, (five) Testing on target hardware is difficult, (six) Safety and reliability requirements.
* Key: At least four challenges for full marks
Q three. Distinguish between microcontroller and microprocessor.
Microprocessor: CPU only, requires external RAM/ROM/peripherals, high power, general purpose (e.g., Intel Core). Microcontroller: CPU plus RAM plus ROM plus I/O all on one chip, low power, used in embedded systems (e.g., ARM Cortex-M).
* Key: All-in-one versus separate components
Q four. Compare top-down and bottom-up design methodologies.
Top-Down: Start from system requirements, decompose into sub-modules. Bottom-Up: Start from basic components, combine to form system. Top-down ensures system-level correctness; bottom-up promotes component reuse.
* Key: Direction of design decomposition
Q five. What is the need of microprocessor in embedded system?
Microprocessor provides computational intelligence to the embedded system - it executes the control algorithm, processes sensor data, makes decisions, and controls actuators. Without it, only hard-wired logic would be possible.
* Key: Intelligence plus flexibility plus control
Q six. What is UML? Give its significance in embedded system design.
UML (Unified Modeling Language) is a graphical notation standard for visualizing, specifying, and documenting software systems. In embedded systems, it is used to model state machines, class diagrams, sequence diagrams, and use case diagrams before implementation.
* Key: Modeling tool for design visualization
Q seven. What is meant by requirement analysis? Why is it important?
Requirement analysis is the process of identifying what the system must do (functional requirements) and how it must behave (non-functional: speed, power, size). It is important to avoid design errors early, as fixing bugs later is one hundred times more expensive.
* Key: What the system must do
Q eight. Enumerate the services to be provided by consumer electronics.
Consumer electronics must provide: (one) User-friendly interface (display, buttons), (two) Multiple media formats (audio/video), (three) Connectivity (WiFi, Bluetooth), (four) Long battery life, (five) Low cost, (six) Safety and durability.
* Key: User-centric services
Q nine. Why is platform compatibility critical in consumer electronics?
Platform compatibility ensures software and peripherals work correctly across different hardware versions and operating systems. Incompatibility leads to product failures, costly redesigns, and poor user experience.
* Key: Interoperability across hardware
Q ten. What is Quality Assurance in embedded systems? Name two techniques.
QA is the process of ensuring an embedded system meets its requirements for correctness, reliability, and performance. Techniques: (one) Black-box testing - test based on I/O behavior, (two) White-box testing - test based on internal code structure.
* Key: Ensuring system meets specifications
UNIT TWO: ARM PROCESSOR AND PERIPHERALS ARM Architecture | Instruction Set | PWM | Timer | UART | Stacks | Subroutines
UNIT TWO: ARM PROCESSOR AND PERIPHERALS ARM Architecture | Instruction Set | PWM | Timer | UART | Stacks | Subroutines
Stack: Fixed-size memory region, automatically managed (PUSH/POP), grows downward, used for local variables and return addresses. Heap: Dynamic memory region, manually managed (malloc/free), grows upward, used for dynamically allocated data.
* Key: Stack equals automatic, Heap equals dynamic
Q ten. Explain the operation of instruction: ADD R three, R two, R one, LSL number three.
LSL number three shifts R one left by three bits (equivalent to R one times eight). Then R two is added to the shifted value. Result: R three equals R two plus (R one times eight). This is a barrel shifter operation combined with addition - unique to ARM's flexible second operand.