embedded system short question answers for anna university

1. Embedded ANNA-UNI
Answered by GPT-4
OCR by Gemini vision
Reviewed by Adhithya
1 What is the purpose of Watch dog timer?
A watchdog timer (WDT) is a hardware timer that automatically gen-
erates a system reset if the main program neglects to periodically ser-
vice it. It is often used to automatically reset an embedded device that
has gone out of control due to software or hardware faults.
2 Mention the features of CAN and SPI serial interfaces.
CAN (Controller Area Network) is a robust and efficient serial com-
munication protocol that supports error detection and signal prioriti-
zation, making it suitable for automotive and industrial applications.
SPI (Serial Peripheral Interface) is a synchronous serial communication
interface that allows full duplex communication and supports high data
rates, making it ideal for short-distance communication in embedded
systems.
3 What is the difference between hard and soft real-time sys-
tems?
Hard real-time systems are those in which the correctness of the
system depends not only on the logical result of computation, but also
on the time at which the results are produced. Failure to meet timing
constraints results in system failure.
Soft real-time systems, on the other hand, can tolerate lateness and
the system performance degrades rather than failing if deadlines are
missed.
4 What are the processes involved in building an embedded
system?
1

2. The processes involved in building an embedded system include defin-
ing the system requirements, system design, implementation, testing,
debugging, and maintenance.
5 Compare Preemptive and Non-preemptive scheduling.
Preemptive scheduling allows a process to be interrupted in the
midst of its execution, taking the CPU away and allocating it to another
process.
Non-preemptive scheduling, on the other hand, once a process has
the CPU, it runs to completion and the CPU cannot be taken away.
6 What are the functions of an embedded system?
The functions of an embedded system depend on the application. They
typically include data collection, data processing, control of operations,
and user interface management.
7 Define Threads and Process.
A process is an instance of a program in execution, while a thread is
a lightweight process and constitutes the smallest unit of processing.
Multiple threads can exist within one process and share resources such
as memory, while different processes do not share these resources.
8 What are the challenges in building an embedded system?
Challenges in building an embedded system include real-time con-
straints, limited memory and processing resources, power consumption,
system stability, and the need for specific domain knowledge.
9 List the different stages of EDLC.
EDLC (Embedded Design Life Cycle) typically includes the follow-
ing stages: Requirement analysis, System architecture design, Detailed
system design, System implementation, System testing, System inte-
gration and debugging, and System maintenance.
10 What are the typical characteristics of an embedded system?
Typical characteristics of an embedded system include: specific func-
tionality, real-time operation, low power consumption, compact size,
robust operation, and cost-effectiveness.
11 Define bus.
2

3. In computer architecture, a bus is a communication system that trans-
fers data between components inside a computer, or between comput-
ers.
12 Give the limitations of polling technique.
Limitations of the polling technique include inefficiency, as the CPU
is often kept waiting while the I/O devices are busy. This can lead to
poor CPU utilization. It also leads to increased latency as the CPU
checks each device in turn.
13 Compare Dataflow model and finite state model.
In the dataflow model, the control of the program is determined by
the flow of data, while in the finite state model, the execution of the
program is determined by the current state and the input.
14 What are the challenges in building an embedded system?
Challenges in building an embedded system include real-time con-
straints, limited memory and processing resources, power consumption,
system stability, and the need for specific domain knowledge.
15 Classify Electronic Control Unit (ECU). Give its uses.
An Electronic Control Unit (ECU) is a type of embedded system in au-
tomotive electronics that controls one or more of the electrical systems
or subsystems in a vehicle.
Types of ECU include engine control module, powertrain control mod-
ule, Transmission Control Module, Brake Control Module, Central
Control Module and others.
16 List any four applications of embedded system.
Applications of embedded systems include: Home automation systems,
Medical equipment, Telecommunication systems, Consumer electron-
ics, and Automotive systems.
17 What are the challenges involved in building an embedded
system?
Building an embedded system involves several challenges including real-
time computing, power consumption, system cost, system size, and
system reliability.
3

4. 18 Point out the purpose of Device Driver.
A device driver is a software component that allows the operating sys-
tem and other applications to interact with hardware devices.
19 What is state machine model?
A state machine model is a model of computation that describes the
behavior of a system in each state, and how it transitions from one
state to another.
20 Mention the features of CAN and SPI serial interfaces.
CAN and SPI are both serial interfaces. CAN is a multi-master se-
rial bus standard for connecting electronic control units, while SPI is
a synchronous serial communication interface used for short distance
communication.
21 What are the functions of RTOS?
The functions of RTOS include managing the system resources, schedul-
ing tasks, handling interrupts, and providing a software platform for
application development.
22 Define Semaphore signaling.
Semaphore signaling is a method used in concurrent programming to
control access to shared resources.
23 What is the purpose of cache memory?
The purpose of cache memory is to store program instructions and data
that are used frequently by the processor.
24 Mention any 4 real time operating system.
Four real-time operating systems are: RTLinux, VxWorks, QNX, and
FreeRTOS.
25 What is the basic requirements while designing an embedded
system?
The basic requirements while designing an embedded system include
defining the system functionality, selecting the appropriate hardware
and software, and testing and debugging the system.
26 How can an embedded system be classified?
An embedded system can be classified based on functionality, perfor-
mance, and complexity.
4

5. 27 Compare different events involved in the smart card applica-
tion?
Smart card applications involve various events such as card insertion,
card removal, data reading, data writing, and authentication. These
events can occur in different orders and combinations depending on the
specific application and user interactions.
28 List the different stages of EDLC.
The different stages of the Embedded System Development Life Cycle
(EDLC) include system specification, architecture design, detailed de-
sign, coding and testing, system integration, and system maintenance.
5