JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B. Tech IV EMBEDDED SYSTEM DESIGN Previous Question Paper (September - 2021 - R16)

Embedded systems are designed for specific tasks with high reliability and efficiency. Their key characteristics include:

• Application Specificity: Designed to perform a dedicated function rather than general-purpose computing.
• Reactive and Real-time: Must respond to external stimuli within strict time constraints.
• Resource Constraints: Limited memory, processing power, and power consumption requirements.
• Hardware-Software Co-design: Tight integration between hardware components and software logic.

Quality attributes define the non-functional requirements:

• Reliability: The probability that the system performs its intended function without failure for a specified time.
• Maintainability: The ease with which the system can be modified to correct faults or improve performance.
• Scalability: The ability of the system to handle increased load or expand functionality.
• Portability: The capability of the software to run on different hardware platforms with minimal changes.

Embedded systems are classified into three categories based on their complexity and performance requirements:

• Small-Scale Embedded Systems: These are designed with 8-bit or 16-bit microcontrollers. They have limited processing power and memory, and are typically used for simple, single-function applications like washing machine controllers or toys. They are not performance-intensive and often operate in a non-real-time environment.
• Medium-Scale Embedded Systems: These utilize 16-bit or 32-bit microcontrollers, DSPs, or RISC processors. They involve more complex hardware and software, often requiring an embedded operating system (RTOS) to manage tasks. Examples include industrial process controllers, networking equipment, and automotive engine control units.
• Sophisticated (Large-Scale) Embedded Systems: These systems are highly complex, requiring high-performance processors like FPGAs, ASICs, or multi-core SoCs. They handle massive data processing, complex algorithms, and often feature graphical user interfaces. They require a robust RTOS or even a general-purpose OS (like embedded Linux) to manage hardware resources. Examples include smartphones, medical imaging systems, and aerospace navigation systems.