Top 25 Embedded Systems Interview Questions and Answers in 2022

An embedded system is a combination of hardware and software designed to perform a specific function on a computer. The system executes a predetermined function or software. It is utilized in the majority of sectors. Due to continuous expenditures in artificial intelligence and computers, the embedded industry is projected to expand rapidly. Thus, there is ample employment potential. Here are some helpful interview questions and answers on embedded systems. These are the 25 most often asked interview questions.

1. What Exactly Is The Term “Embedded System ” In A Computer System”?

An embedded system is a microprocessor-based computer hardware and software system designed to execute a specific purpose independently or as a component of a more extensive procedure. An integrated circuit designed to do the calculation for real-time processes is at the center.

The spectrum of complexities is vast, from a single microcontroller to a suite of processors with associated peripherals and networks, from no user interface to complicated graphical user interfaces. The complexity of an embedded system varies considerably based on its function. Applications of embedded systems include digital watches, microwaves, hybrid automobiles, and avionics. Up to 98 percent of all produced microprocessors are for embedded systems.

2. What Exactly Does “Embedded Software” Mean?

Embedded software is a subcategory developed to function properly on various hardware. This hardware is almost always incorporated into another, more powerful system, like a vehicle or a washing machine. The program is developed to be compatible with the particular hardware used. As a result, it is typically not adaptable to function with any other kind of hardware.

3. What Are Some Of The Ways We Use Timers In Embedded Systems?

Timers in embedded systems can have numerous purposes, including the following:

  • The system’s Real Time Clock abbreviation is RTC.
  • Kicking off an event following a delay of a certain amount of time.
  • The beginning of an event follows a comparison of the previously specified times.
  • Taking note of the count value displayed by the timer on an event.
  • Determining the amount of time that has passed between two events.
  • Time-slicing for a variety of different activities.
  • Multiplexing using time division (TDM).
  • RTOS task scheduling for all of the other jobs.

4. What Does Dma Mean In The Context Of An Embedded System?

The abbreviation “DMA” refers to “Direct Memory Access” in an embedded system. It is a process that enables an input/output (I/O) device to send or receive data from the main memory. In other words, it allows the device to communicate with the main memory. The Direct Memory Access (DMA) procedure is managed by a DMA controller (DMAC) chip. DMA channels are responsible for data communication between the system’s memory and the peripheral devices.

5. Could You Describe What A Watchdog Timer Is And How It Works?

A watchdog timer (WDT) is a timer that watches microcontroller (MCU) programs to determine whether or not they are out of control or have ceased operation. It serves as a “watchdog” for MCU operations. A microcontroller (MCU) is a small controller used to manage electronic devices. MCUs are pre-loaded with program software whose commands control electronic equipment and are integrated into a wide variety of electronic devices.

It makes it essential to ensure regular MCU operation. In the worst-case scenario, if the MCU software becomes unmanageable or stops functioning, the electronic equipment may behave unpredictably, resulting in damage or an accident.

6. Describe The Attributes Of An Embedded System.

Embedded systems come in various sizes and designs. It ranges from massive data storage systems with several racks to small components such as MP3 players and cell phones.

The following are some of the critical properties of an embedded system:

  • It contains the engine for processing.
  • The embedded systems are intended for a specific application. They contain a primary user interface similar to an automobile’s engine ignition.
  • Embedded systems often have a straightforward user interface and power constraints. As some embedded systems only work on battery power,
  • The application software is primarily embedded within the integrated system, and the user does not select it.
  • Applications intended for use with embedded systems do not require human intervention.

7. What Are The Various Embedded System Types?

The embedded system is categorized into four major groups:

  • Embedded systems: The autonomous embedded system works without a computer host. It receives digital or analog input from input ports. It sends the data to a connected device that controls associated devices. MP3 players, digital cameras, video games, and temperature measurement systems are embedded.
  • Real-time embedded: This system requires timely output. It meets task deadlines. Real-time embedded systems might be soft or rigid.
  • Networked embedded system:- This sort of embedded system uses networks to access resources. LAN, WAN, or the internet connection. Wired or wireless connections are possible. Today’s most popular embedded system is networked; all embedded devices are controlled by a web browser and protected by IP/TCP.
  • Mobile embedded systems are desired. Mobile phones, digital cameras, wireless mp3 players, etc. This embedded system’s memory is restricted.

8. What Are The Component Elements Of An Embedded System?

Primarily, an embedded system’s components are divided into three categories:

  • Hardware Components: The various hardware components of an embedded system consisting of a power supply, CPU, memory, timer-counters, communication ports, input and output, and application-specific circuits such as a temperature sensor or alarm buzzer.
  • Software Components: An embedded system’s components include an assembler, an emulator, a debugger, and a compiler.
  • Real-Time Operating System (RTOS): This system’s purpose is to supervise software components and provide a way for a processor to execute a process according to a schedule.

9. What Are Some Of The Benefits Of Using Java In Embedded Systems?

An embedded system using Java often handles real-time operations that are complex but not particularly challenging. It features a tiny footprint while still providing good performance. It speeds up the development process and cuts down on errors. Because Java comes with its collection of standard libraries, there is no requirement to rewrite the functionality. It offers a high level of development productivity, which is essential for an embedded system.

10. What Skills Are Necessary For Someone To Acquire If They Wish To Work With Embedded Devices?

A person who wants to work with embedded devices should acquire a few essential abilities. First, they must have a solid grasp of electronics and how to design and construct circuits. They should also be adept in programming, as they must be able to develop code for embedded devices. Finally, they must have a solid grasp of the physics and mechanics of the devices to design them so that they perform properly.

11. What Is The Difference Between Firmware And Embedded Software?

A program or set of programs intended to carry out a particular function inside a larger system’s context is called embedded software. The opposite is the case with firmware, which refers to a specific kind of software built into a physical device. Read-only memory (ROM) or flash memory is where it is normally kept, and it serves as the primary controller for the device’s fundamental operations.

12. What Types Of Problems Occur When Working With Embedded Devices?

One problem frequently arises as resource contention, which occurs when two or more devices compete for the same finite resources (memory, processing power, etc.). Real-time restrictions are another potential issue that could arise. In this scenario, particular timing activities are essential, and any delays could result in errors. In addition, difficulties may be encountered while trying to debug and test embedded systems since it may be impossible to simulate the actual conditions in which the system would be working.

13. What Qualities Of An Operating System Make It Suitable For Usage In An Embedded System?

An operating system needs to be compact, fast, able to function well with constrained resources, and adaptable to meet the particular requirements of an embedded system. These are some of the main features that make an OS appropriate for an embedded system. An operating system can’t function properly in an embedded system if it is too big or too slow. Embedded systems often have extremely few resources available to them. In addition, an embedded system will typically need to be tailored for the particular hardware and software it will be running on; hence, an operating system that is not easily adaptable will not be an appropriate choice for an embedded system.

14. How Does Testing For Embedded Software Differ From Testing For Other Forms Of Software, Such As Web And Mobile Applications?

Embedded software is frequently evaluated on the hardware it will run on rather than in a simulator or emulation. It is one of the primary differences. Because the software is meant to interact intimately with the hardware, any defects or faults must be discovered and resolved on the hardware. Another distinction is that embedded software is frequently tested for real-time performance and power consumption, which are crucial aspects of many embedded systems.

15. What Are The Typical Errors Encountered In Embedded Systems?

The types of standard errors seen in embedded systems are:

  • Stack overflow error: The call stack has a finite amount of memory, and excessive memory utilization can lead to an error. Call stack memory contains information about active subroutines in the program.
  • In a program, a segmentation fault occurs when an attempt is made to access nonexistent memory.
  • Memory Leak: This occurs owing to improper memory allocation management. In this memory that is no longer required is not released.
  • Memory fragmentation or corruption occurs when memory is altered without an explicit assignment.

16. What Are The Functions Of Malloc And Calloc?

  • Malloc:- malloc’s primary purpose is to allocate memory at runtime. The size is measured in bytes, and precisely that amount of memory space is allocated.
  • Calloc is comparable to malloc in that it allocates memory at runtime, as described in stdlib.h. The purpose of calloc is to obtain the number of elements. And the size of each element is measured in bytes. Then, they will set each of these elements to zero. A null pointer is then returned to the memory.

17. Why Is It Essential For Embedded Devices To Have A Solid Power Management Strategy?

For embedded devices, it is critical to have a solid power management strategy for several reasons. These reasons are as follows: First, proper power management has the potential to lengthen the amount of time a device’s battery may remain charged. Second, power management can increase system performance by lowering the amount of power consumed. In conclusion, the power management has the potential to assist in lowering system costs by lowering the requirement for additional batteries or power supply.

18. Can User Interfaces Be Designed For Embedded Systems? If Yes, How?

Embedded systems do have the capacity to have user interfaces designed for them. Utilizing a graphical LCD is the most frequent technique to achieve this goal; however, we can take other approaches. The user will be able to interact with the embedded system by navigating the menu system that you will be able to design using this method.

19. In The Case Of Embedded Systems, What Is The Most Effective Technique To Implement Error Handling?

Utilizing a watchdog timer is one method that we may utilize to enable error handling in embedded systems. This timer is used to reset the system if it determines that it is not functioning correctly and has to be reset. It can help to ensure that the system does not get caught in an endless cycle or become unusable in some other way.

20. In An Embedded System, What Does Rtos Stand For?

Real-Time Operating System is the complete version of the acronym RTOS. In an embedded system, the primary function of an RTOS is to provide support for real-time applications. These applications can handle data without being hindered by buffer delays. Additionally, it takes care of the complicated hardware aspects. An embedded system makes use of an RTOS because it is capable of meeting real-time deadlines and can effectively manage complexity.

21. What Are Some Of The Different Ways That Embedded Systems Can Be Applied In Real Life?

The following are the applications:

  • Embedded systems are used to make a speed-checker gadget that identifies dangerous driving on highways and reports to the relevant authorities.
  • Control the street lighting and look for moving vehicles on the highways.
  • The timing of traffic signals in a density-based traffic signal system is controlled by the amount of traffic present at intersections.
  • Utilizing a GPS modem to pinpoint a vehicle’s precise location.
  • Embedded systems are used for a home automation system that utilizes a remote control based on an Android application.

22. What Exactly Is Interrupt? What Kind Of Control Does An Embedded Device Have Over Them?

An interruption is a signal that can be produced by either the computer’s hardware or its software, indicating that a certain kind of event has occurred. Whenever an interrupt is triggered, the embedded device will normally cease the activity it is now engaged in and start running a unique routine designed to handle interrupts. After that, the interrupt handler will determine what generated the interrupt and take the required action.

23. How Does One Go About Developing An Embedded System?

The first thing you need to do is get a good grasp of the system’s requirements. It includes having a solid understanding of the various pieces of hardware and software with which the system will need to communicate. Once the requirements have been comprehended, the subsequent step is designing the system’s various software and hardware components. It covers the design of the software algorithms, the electronics, and the interfaces between the various components. The final step is to do testing on the system to determine whether or not it satisfies the requirements.

24. Is Specialized Hardware Or Software Required For Real-Time Applications? If Yes, Why?

Real-time applications may call either specialized computer hardware or software to fulfill the temporal restrictions that they impose. Because real-time applications need to guarantee that certain events will happen within a specific timeframe, and if the hardware or software cannot meet those requirements, the application will not work correctly. It is because real-time applications need to guarantee that certain events will happen within a specific timeframe.

25. What Are The Essential Parts Of An Embedded System?

Processors, memory, input/output devices, and software are the main components of an embedded system. The system’s processor is responsible for executing the instructions that allow the system to function. Memory is where data and instructions are normally kept, and it is typically classified into two categories: ROM (read-only memory) and RAM (random access memory) (random access memory). Input/output devices, which include sensors, screens, and keyboards, are used to communicate with the outside world. The software instructs the machine on how to operate, and it is often stored in ROM.

Conclusion

As technology advances, many companies want candidates with experience in embedded system design. Suppose you are being interviewed for a position involving embedded systems. In that case, the interviewer will likely ask you about your expertise and understanding of the field.