14.1 C
Saturday, December 10, 2022
Home > Interview TipsBasic Embedded Systems Interview Questions

Basic Embedded Systems Interview Questions

The technical interview is one of the most challenging parts of the hiring process. To win over the interviewers, you must use every skill you can, from making the right first impression to demonstrating your credentials in your CV.

Embedded Systems Interview Questions and Answers are presented here so that you can review them so that you are better prepared to face your interview.

Devices that include a processor are often embedded in other hardware, such as electrical or electronic components. A real-time embedded system needs to have real-time computing capabilities since it controls physical operations within a machine that it is embedded in. Nowadays, embedded systems control a wide range of devices. The percentage of microprocessors used in embedded systems was estimated to be 98% in 2009.

Embedded System Interview Questions

1) What are some real-time applications of embedded processors?

  • Passenger vehicles
  • The Dishwasher
  • Cell phones
  • TV
  • Medications

2) What is the operating system used in embedded systems?

“Real-time operating systems” are used in embedded systems. 8051 has only 256 bytes of memory, and therefore cannot be used to run WINDOWS, LINUX, or any similar desktop operating system.

3) Mention the embedded systems used in aerospace?

  • Control systems for aircraft
  • Automated
  • In-flight embedded system for passengers
  • Controls for engines

4)How many embedded processors are needed to build a modern passenger car?

A total of 50 processors are installed.

5)Explain the FPGA expansion.

Field-programmable gate arrays: FPGAs.

6)Is Machine Code a Program?

Computers only accept machine code or ”object code” instructions. Computer language rather than programmer language. A programmer’s interpretation of the code is complicated and prone to error. Every piece of software, no matter what its format, must be converted into machine code for the computer to execute.

7)What is the maximum oscillator frequency and peak performance of the 8051?

An 8051’s oscillator frequency could reach 12 MHz and its peak performance was 1 MIPS.

8) What are real-time embedded systems?

These systems monitor, respond to and control environmental conditions in real-time. Actuators, sensors, and other input-output interfaces connect this environment to the computer system.

9) Why do embedded systems matter?

By using an embedded microprocessor, hardware logic gates, input buffers, timing circuits, output drivers, and so forth can be replaced.

10) What is a microcontroller?

As an embedded system, a microcontroller is a self-contained system with peripherals, memory, and a processor.

11)What is the DMA address used for?

Physical addresses are DMA addresses. During data transfer, it is a device that drives the data and addresses the bus directly. The address is strictly physical.

12) What is interrupt latency? Can it be reduced?

The interrupt latency is the time it takes to return from an interrupt service routine after handling a specific interrupt.  ISR routines can be written to reduce interrupt latency.

13) What is a Watchdog Timer?

As soon as a problem with an electronic system occurs, a watchdog timer is activated and executes a specific action.

14)What is a semaphore?

Semaphores control access to the same resource by multiple process threads, such as those found in a multiprogramming environment. There are usually two purposes for using semaphores


Using this system, large binary numbers can be represented compactly. In embedded systems, it is widely used. Numbers in hex are signified by the prefix ‘0X’ in C (and elsewhere).

16)Describe the memory regions in 8051 devices.

The 8051 devices have two distinct types of memory. Here they are:

  • It is the area of data
  • This is the code area.

17)Define the Mask read-only memory.

Mask programming is also known as factory-programmed ROM, and it is not cheap. Memory read-only masks operate at 1.5 times the speed of DRAM.

18)Define the prom.

Write-once, read-many (WORM) or “once-to-programmable” (OTP) memory.

19)Define the DRAM.

Information is stored in a small capacitor using a read-write memory technology. To maintain the required information, the capacitor must be periodically refreshed. The information may be lost if the power is cut off to the chip.

20)Define the SRAM.

Information is stored using an electronic flip flop as a read-write memory. Circuits are more complex, but no refreshing is required. It may take one-third as long as DRAM to access data.

IoT Interview Questions

1. Describe Raspberry Pi

As a computer, Raspberry Pi is capable of performing all the operations like a conventional computer. Other features include onboard WiFi, GPIO pins, and Bluetooth for communicating with external devices.

2. Running Raspberry Pi headless – how to?

SSH can be used to run Raspberry Pi in headless mode. For remote desktop access on a Raspberry Pi, the latest operating system has an inbuilt VNC server.

3. Stack of IoT protocols

According to the IoT protocol stack, there are four layers: 1) Sensing and information, 2) Network connectivity, 3) Information processing layer, and 4) Application layer.

4. Arduino: Define

Unlike many other platforms, Arduino uses hardware and software that is easy to use. The microcontroller can read sensor inputs and control the motors programmatically.

5. The most common types of sensors in IoT

IoT sensors mostly use the following types:

  • Sensor for smoke
  • Thermometers
  • Sensor for pressure
  • Sensors that detect movement
  • Sensor for gas
  • Sensors that measure proximity
  • Sensors for IR

6. How does IoT differ from the business of sensors?

A sensor business doesn’t need to be connected to the Internet. To work, the Internet of Things needs a control side.

7. PWM is what?

Pulse Width Modulation is a method of varying how long the signal is high in analog form. Users can change the percentage of time as well as signal strength.

8. Describe how PWM is used in IoT

PWM can be used in a wide range of IoT applications, such as controlling a DC motor’s speed or motor’s direction, dimming LEDs, etc.

9. Low energy Bluetooth – what is it?

This wireless technology is a Personal Area Network (PAN) based on Bluetooth Low Energy. Short-distance transmission requires less power than long-distance transmission.

10. Defining MicroPython

MicroPython is a fragment of the Python standard library that implements some of it. ModeMCU microcontrollers can be used to optimize it.

11. To communicate reliably between two devices, how many wires are required, and why?

For communication with larger computers, such as being used to download firmware, serial communication is often used as a technique similar to the TTL protocol. TTL serial communication uses two wires, one for TX (transmit) and one for RX (receive). However, there also needs to be a common ground-level shared between the devices, so the minimum number of wires required for TTL serial communication is three. (I2C and SPI require a common electrical ground.)

People Also Interested In:

More Resources : jobs in Chennai for freshers | jobs in Lucknow for graduate | whitehat jr interview questions | electrical interview questions

- Advertisement -spot_img

More articles

- Advertisement -spot_img

Latest article