Top 30+Embedded C Interview Question and Answers 2024

Embedded C  is the most well-liked language due to its simplicity, effectivity and for its portability from one system to a different.

Given that {hardware} sources like CPU and reminiscence sizes are constrained for embedded techniques, it’s essential to make use of these sources correctly and ethically. Embedded C sometimes has the suitable abstractions to speak with the {hardware} sources as a way to accomplish this.

Whether you’re a school scholar looking for an embedded techniques internship, a current graduate searching for an embedded software program job, or a full-time embedded techniques engineer attempting to alter positions or firms, we may also help. To get the place you want, you’ll at all times need to undergo a number of technical interviews. So, this text has a compiled checklist of embedded c interview questions that helps inexperienced persons, intermediate and skilled candidates.

If you’re acquainted with embedded ideas, many prime firms provide positions resembling embedded developer in C/C++, embedded developer in software program improvement & structure, embedded developer in C/C++, embedded C programmer, embedded firmware developer in C/C++, senior engineer/tech lead in C/C++, amongst many others.

Here is  the checklist of prime 10 embedded c interview questions 

What is an Embedded System?

It is an software that accommodates no less than one programmable pc, which is often within the type of a microprocessor, microcontroller or digital sign processor chip.

What is Embedded C Programming? How is Embedded C completely different from C language?

Embedded C is a C language extension that’s used to create functions for microcontrollers. The I/O Hardware Addressing, fixed-point arithmetic operations, accessing tackle areas, and so on. are enhancements within the Embedded C language from the usual C programming language. There are 5 layers of fundamental buildings in an embedded C programme. As follows: 

Comment: To make it simpler for the person to know, this textual content has been transformed into easy, readable code. Comments are sometimes written in / or /* */. 

Pre-processor directives: The Pre-Processor directives specify which information the compiler ought to seek for lacking symbols in. 

Global Declaration: The part of this system’s code the place world variables are declared. Local Declaration: The part of code that defines native variables. 

Main Function: Every C programme has a major perform that controls the complete program’s code. The execution element and the declaration half make up the majority of it. Whereas the execution element specifies the general construction of programme execution, the declaration half is the place all variables are outlined. 

Is the Embedded System computer-based?

The Embedded System is computer-based.

Tell Me Some Real-Time Applications Of Embedded Processors?

Some real-time functions are: 

• Passengers vehicles
• Dishwashers
• Mobile Phones
• Television
• Medical tools, and so on.

Tell Me About The Facts That You know About 8051 Architecture?

• It was initially developed by Intel and carried out in additional than 400 chips. These are produced by a various vary of firms, together with Philips, Infineon, Atmel and Dallas.

How are Embedded Systems developed?

The low worth and simple availability of the 8051 households make it a superb platform for creating embedded techniques.

How Many Bits That Embedded Software Support?

It helps 8, 16 or 32-bit embedded processors.

Which Operating System Is Used In Embedded Systems?

The working system utilized in an embedded system is a “real-time operating system”. The 256 bytes of reminiscence within the 8051 is inadequate to help any model of WINDOWS, LINUX, or Similar desktop working techniques.

Mention The Embedded System In Mobile Phone?

It consists of each the shopper handset and the Base station.

Tell Me The Embedded System In Automotive Applications?

• Braking system
• Steer-by-wire system
• Traffic management
• Cruise management functions.
• Airbag launch system
• Engine administration models.

Tell Me The Domestic Appliances Which Include Embedded System?

• Dishwashers
• Garage door controllers
• Televisions
• Washing machines
• Microwave ovens
• Video recorders and
• Security techniques Etc.

Mention The Embedded System In Aerospace Applications?

• Flight management techniques
• Autopilot
• A passenger in-flight embedded system
• Engine controllers

Tell Me The Embedded System Which Includes Medical Equipment? 

• Anaesthesia monitoring techniques
• ECG displays
• Drug supply techniques and 
• MRI Scanners

Mention the Embedded Systems Which Includes Defense System?

• Radar techniques
• Fighter plane flight management system
• Radio techniques
• Missile steering techniques.

List out The Discrete Components.

• Transistors
• Diodes
• Resistors
• Capacitor

  Explain The Circuit under

The Above Circuit explains about ‘cupboard light application’. The Processor used within the above circuit is AtmelAT89C2051.It is meant to be used in a cabinet and might be battery-powered. When the sunshine is switched on, particularly whereas urgent the change, it can function for 20 seconds. If the USER doesn’t press the change once more (to show off the sunshine), The energy might be eliminated robotically. It is a straightforward circuit and produced utilizing a microcontroller.

Define Extended 8051 Device.

Extended 8051s have extra on-chip amenities and extra port pins. In the case of Infineon, the opposite amenities embrace help for the ‘Controller Area Network’ (CAN) bus.CAN bus is extensively used within the automotive sector and industrial environments.

How many Embedded Processors are Needed To Manufacture a Modern Passenger Car? 

Around 50 Processors are on board.

Tell Me The Expansion Of FPGA.

FPGAs: field-programmable gate arrays.

What Is Machine Code?

Computers solely settle for directions in “machine code” or ‘’object code’’. It is the language of the pc RATHER than the Programmer. The interpretation of the code by the programmer is complicated and error-prone. Whether in meeting, C, C++, Java, or Ada, all software program should finally be translated into machine code to be executed by the pc.

Explain 8051 FEATURES.

Embedded processors like 8051 have restricted processor energy and minimal energy obtainable. The language used have to be environment friendly. It has an extended lifespan.

Embedded system options on c.

It may be very environment friendly, standard and effectively understood. Even desktop builders who’ve used solely Java or C++ can quickly perceive c syntax. Good and well-proven compilers can be found for each embedded Processor.

Write this system for the tremendous loop demonstration.

Void major( void)
               {
                 //put together run perform x
                 X_Init();
                While(1)  //  ‘for ever’ (tremendous loop)
                      {
                        X(); // Run perform x()
                       }
                 }

Describe the hyperlink between oscillator frequency and machine–cycle interval.

        
As a normal rule, the pace at which your software runs is instantly decided by the oscillator frequency. In most instances, If you double the oscillator frequency, the applying will run twice as quick.

Expand MIPS.

MIPS: Million directions per second.

What are the vary of most oscillator frequency and the height efficiency in 8051?

The 8051 had a most oscillator frequency of 12 MHz, and peak efficiency is 1 MIP.

How to enhance the 8051 efficiency?

The easy method to enhance the efficiency of the 8051 microcontrollers is to extend the clock frequency. The 8051 units enable the usage of clock speeds effectively past the 12MHz restrict of the unique units. The greatest method to enhance the efficiency is to make inside adjustments to the microcontroller in order that fewer oscillator cycles are required to execute every machine’s instruction.

What are the forms of reminiscence in an Embedded System on C?

• DRAM(Dynamic RAM)
• SRAM(Static RAM)
• Mask Read-only Memory (ROM)
• PROM(Programmable Read-Only Memory)
• UV EPROM(UV Erasable Programmable Read-Only Memory)
• EEPROM (Electrically – Erasable PROM)

Embedded C Interview Questions

Define DRAM.

It is a read-write reminiscence know-how and makes use of a small capacitor to retailer info. The capacitor will discharge quickly and have to be continuously refreshed to take care of the required info. There is an opportunity that the data is misplaced when energy is faraway from the chip.

Define SRAM.

It is a read-write reminiscence know-how and makes use of a type of digital flip flops to retailer the data. No refreshing is required, however the circuit is extra complicated. The entry time could also be one–third these of DRAM.

Define Mask read-only reminiscence.

It is also referred to as factory-programmed ROM, and masks programming is just not low-cost. ACCESS TIME of masks read-only reminiscence is 1.5 instances slower than the DRAM.

Define promenade.

It is a type of write-once, read-many (WORM) or “one–time programmable” (OTP) reminiscence.

Define UV EPROM.

Like PROM, UV EPROMs are programmed electrically. Unlike PROMs, they’ve a Quartz Window that permits the reminiscence to be erased by exposing the system’s internals to UV mild. The quartz window might be lined with a UV-opaque label. This EPROM can stand up to hundreds of Programs/ erase cycles. It is extra versatile than PROMs and can be utilized in prototyping.

Define EEPROM.

It is a extra user-friendly type of ROM that may be each programmed and erased-friendly. It might be often reprogrammed by byte by byte foundation. It is used to retailer passwords and different persistent person information.

Define FLASH ROM.

It is a extra user-friendly type of ROM that may be each programmed and erased simply.  EEPROM and FLASH ROM are each comparable to one another. It typically required a blocked–sized erase operation earlier than programming.

Define HEXADECIMAL.

It is a base- 16 numbering scheme which supplies a compact method of representing giant binary numbers. It is extensively utilized in embedded techniques. The prefix ‘0X’ is utilized in C( and elsewhere) to point {that a} quantity is in ‘hex’ notation.

Name the reminiscence areas in 8051 units.

There are two forms of distinct reminiscence areas within the 8051 units. They are:

• The information space
• The code space.