Top 50 Embedded Systems Interview Questions and Answers 2024

Microcontroller is a compact computer on a single chip with built-in memory and peripherals, while microprocessor is just a CPU.

• Microcontroller has on-chip memory and peripherals, while microprocessor requires external memory and peripherals.

• Microcontroller is used in embedded systems, while microprocessor is used in personal computers.

• Examples of microcontrollers include Arduino, PIC, and AVR, while examples of microprocessors include Intel Pentium, AMD Ryzen, and ARM Cortex...read more

Microprocessors are general-purpose CPUs while microcontrollers are designed for specific tasks.

• Microprocessors are used in computers, smartphones, and other devices that require complex processing.

• Microcontrollers are used in embedded systems, such as home appliances, automotive systems, and medical devices.

• Microprocessors have separate memory and I/O interfaces while microcontrollers have them integrated on a single chip.

• Microprocessors are more expensive than microcontroll...read more

Embedded systems are useful for controlling and monitoring various devices and systems.

• Embedded systems are used in a wide range of applications such as consumer electronics, automotive systems, industrial automation, and medical devices.

• They provide real-time control and monitoring capabilities, allowing devices to respond quickly and accurately to external events.

• Embedded systems are often used in safety-critical applications where reliability and stability are crucial.

• They...read more

Embedded automation is used for specific tasks while PLC automation is used for controlling entire systems.

• Embedded automation is used for a single task or function, such as controlling a motor or sensor.

• PLC automation is used for controlling entire systems, such as a manufacturing plant or assembly line.

• Embedded automation is typically programmed in low-level languages such as C or assembly, while PLC automation is programmed using ladder logic or other high-level languages....read more

Microprocessor is a CPU on a single chip while Micro-controller is a CPU with integrated memory and peripherals.

• Microprocessor is used in general-purpose computing while Micro-controller is used in embedded systems.

• Microprocessor requires external memory and peripherals while Micro-controller has them integrated.

• Examples of Microprocessors are Intel Pentium, AMD Ryzen while examples of Micro-controllers are Arduino, Raspberry Pi.

• Microprocessors are more powerful and expensive...read more

A watchdog timer is a hardware or software component that monitors the operation of a system and resets it if necessary.

• A watchdog timer is used to prevent system crashes or lock-ups by resetting the system if it becomes unresponsive.

• It is typically implemented as a counter that needs to be periodically reset by the system software.

• If the watchdog timer is not reset within a certain time period, it triggers a system reset.

• Watchdog timers are commonly used in embedded systems,...read more

Timers and counters are essential in embedded systems for tasks like scheduling, measuring time intervals, generating waveforms, and counting events.

• Timers are used for scheduling tasks at specific intervals, generating PWM signals, and measuring time durations.

• Counters are used for counting external events like pulses, frequency measurement, and capturing input signals.

• Timers and counters are crucial for real-time applications, communication protocols, and controlling hardwa...read more

I have 5 years of experience in Embedded design.

• Designed and developed embedded systems for various applications

• Proficient in programming languages such as C, C++, and Assembly

• Experience in working with microcontrollers and microprocessors

• Developed firmware for IoT devices

• Designed and implemented communication protocols such as SPI, I2C, UART

• Experience in debugging and troubleshooting hardware and software issues

It depends on the requirements and constraints of the project.

• If the project has limited resources, a bare-metal approach without an OS may be more appropriate.

• If the project requires complex functionality and multitasking, an OS may be necessary.

• An OS can provide better security and easier maintenance.

• Examples of OS for embedded devices are FreeRTOS, uC/OS, and Linux.

• Consider the cost and time-to-market implications of using an OS.

Embedded projects involve designing and developing systems that are integrated into larger systems or devices.

• Embedded projects require knowledge of hardware and software integration.

• They often involve programming microcontrollers or microprocessors.

• Examples include designing a smart thermostat, a wearable fitness tracker, or an automotive infotainment system.

PLCs are specialized computers used for industrial automation, while microcontrollers are small computers used in various electronic devices.

• PLCs are designed for controlling industrial processes, while microcontrollers are used in a wide range of electronic devices.

• PLCs are typically programmed using ladder logic or other specialized languages, while microcontrollers are programmed using C/C++ or other high-level languages.

• PLCs are more robust and reliable for industrial app...read more

IoT devices are connected to the internet and can communicate with other devices, while embedded systems are standalone and perform specific tasks.

• IoT devices are designed to be connected to the internet and can communicate with other devices through the internet.

• Embedded systems are standalone devices that perform specific tasks and are not designed to be connected to the internet.

• IoT devices are typically more complex and have more processing power than embedded systems.

• Emb...read more

UART can be used to receive signals from a microcontroller.

• Connect the UART pins of the microcontroller to the UART pins of the receiving device.

• Configure the UART settings such as baud rate, parity, and stop bits.

• Use a UART library or write code to read the incoming data from the UART buffer.

• Process the received data as required by the application.

The tolerance of SPI (Serial Peripheral Interface) is typically specified by the manufacturer and can vary depending on the specific device.

• SPI tolerance is usually specified in terms of clock frequency, voltage levels, and timing requirements.

• Different SPI devices may have different tolerance levels, so it is important to refer to the datasheet for accurate information.

• For example, a certain SPI device may have a clock frequency tolerance of +/- 5%.

• Voltage level tolerance ma...read more

A slave in an embedded system can handle two masters by using a bus arbitration mechanism.

• The slave device can prioritize requests from one master over the other based on a predefined protocol.

• The slave can use a bus arbitration technique such as round-robin or priority-based arbitration to manage access from multiple masters.

• The slave may have separate buffers or registers to store data from each master to prevent data corruption or loss.

• The slave can communicate with both m...read more

Timers are used to measure time intervals, while counters are used to count events or occurrences.

• Timers are typically used for generating delays, measuring time intervals, or triggering events at specific times.

• Counters are used to count external events, such as pulses or interrupts.

• Timers can be used to implement software delays, while counters can be used for tasks like frequency measurement.

• Examples: A timer can be used to generate a periodic interrupt every 1 millisecond...read more

Arduino is an open-source electronics platform based on easy-to-use hardware and software.

• Arduino is used for prototyping and creating interactive electronic projects

• It can be used for home automation, robotics, and IoT applications

• Arduino boards can be programmed using the Arduino IDE

• Arduino has a large community and library of pre-built code and projects

• Examples of Arduino projects include a smart thermostat, a robot arm, and a weather station

Embedded new ideas refer to innovative concepts and solutions that can be implemented in embedded systems.

• Embedded new ideas can improve the functionality, performance, and efficiency of embedded systems.

• Examples of embedded new ideas include the use of machine learning algorithms, IoT integration, and real-time data processing.

• Embedded new ideas can also involve the development of new hardware components or the optimization of existing ones.

• Incorporating security features an...read more

Smooth running can be achieved by effective project management techniques.

• Establish clear project goals and objectives

• Create a detailed project plan with timelines and milestones

• Assign roles and responsibilities to team members

• Regularly communicate with team members to ensure everyone is on the same page

• Monitor progress and adjust the plan as needed

• Address any issues or conflicts promptly

• Celebrate successes and recognize team members for their contributions

Embedded means something that is fixed firmly and deeply within something else.

• Embedded refers to something that is enclosed or firmly fixed within something else

• In technology, embedded systems are specialized computer systems that are part of a larger device or system

• Embedded software is computer software that is written to control machines or devices

• Embedded journalism refers to reporters who are embedded with military units during conflicts

ECU and MCU Configuration refers to the setup and programming of electronic control units and microcontroller units in a system.

• ECU and MCU Configuration involves setting up and programming electronic control units and microcontroller units in a system

• This configuration is important for ensuring proper functioning of the system

• Examples of systems that require ECU and MCU Configuration include automobiles, industrial machinery, and medical devices

Software designed to run on embedded systems with limited resources and specific functions.

• Embedded software is tailored to the specific hardware it runs on.

• It is often written in low-level languages like C or assembly.

• It must be efficient and optimized for limited resources like memory and processing power.

• Examples include firmware for a smart thermostat or a car's engine control unit.

Firmware update over the air is the process of remotely updating the software on a device without requiring physical access.

• OTA updates allow for seamless and convenient updates to devices without user intervention.

• Devices must be connected to the internet to receive OTA updates.

• OTA updates can be scheduled to minimize disruption to users.

• Security measures must be in place to ensure the integrity of OTA updates.

• Examples of devices that receive OTA updates include smartphones,...read more

The latest embedded systems are focused on IoT, AI, and machine learning.

• Embedded systems are becoming more connected to the internet of things (IoT)

• AI and machine learning are being integrated into embedded systems for improved performance

• Low-power consumption and high-performance processors are being developed for embedded systems

• Examples include Amazon Echo, Nest Thermostat, and Fitbit

I2C is a serial communication protocol used to connect multiple devices on a bus.

• I2C stands for Inter-Integrated Circuit

• It uses two wires - SDA (data line) and SCL (clock line)

• Devices on the bus are addressed using unique 7-bit addresses

• Supports multiple masters and slaves on the same bus

• Data is transferred in 8-bit bytes with start and stop conditions

• Commonly used in sensors, EEPROMs, and other integrated circuits

A variable's value in an embedded device is typically set through initialization in the code or through external input.

• Variables can be initialized with a specific value in the code during declaration.

• Values can also be set dynamically during runtime through user input or sensor data.

• Some variables may have default values set by the firmware or hardware.

• Values can be updated through communication protocols like UART, SPI, or I2C.

• Variables can be modified through interrupts or...read more

Embedded s/m refers to software that is integrated into hardware devices to perform specific functions.

• Embedded s/m is designed to perform specific tasks and is often used in devices such as smartphones, cars, and medical equipment.

• It is different from traditional software as it is tightly integrated with the hardware and cannot be easily removed or replaced.

• Examples of embedded s/m include firmware in a printer, operating system in a smartwatch, and control software in a dro...read more

Keyboard mapping in a microcontroller involves assigning specific key codes to each key on the keyboard.

• Keyboard mapping is typically done using a lookup table that maps physical key presses to corresponding key codes.

• The microcontroller reads the key code when a key is pressed and sends it to the computer for processing.

• Keyboards may use different mapping standards such as ASCII or HID.

• Custom keyboard mappings can also be implemented for specific applications or languages.

Embedded systems are specialized computing systems designed to perform specific tasks, often with limited resources. Programming languages used for embedded systems include C, C++, and assembly.

• Embedded systems are dedicated computing systems designed to perform specific functions.

• They are often used in devices like smartphones, smartwatches, and automotive systems.

• Programming languages commonly used for embedded systems include C, C++, and assembly.

• These languages are chosen...read more

Microprocessor is a standalone CPU while microcontroller has CPU, memory, and peripherals on a single chip.

• Microprocessor is used in general-purpose computing devices like computers, while microcontroller is used in embedded systems.

• Microprocessor requires external components like memory and peripherals, while microcontroller has them integrated on the chip.

• Examples of microprocessors include Intel Core i7, AMD Ryzen, while examples of microcontrollers include Arduino, PIC, a...read more

Embedded development is the process of creating software that is embedded into hardware devices to control their functions.

• Involves programming microcontrollers or microprocessors

• Requires knowledge of hardware and software interactions

• Common in devices like smartphones, IoT devices, and automotive systems

Embedded systems are specialized computing systems designed to perform specific tasks within a larger system.

• Real-time embedded systems

• Networked embedded systems

• Mobile embedded systems

• Standalone embedded systems

I have experience securing embedded systems IoT products through implementing encryption, authentication, and secure coding practices.

• Implemented encryption algorithms such as AES for data protection in IoT devices

• Implemented secure authentication mechanisms like two-factor authentication for user access control

• Ensured secure coding practices such as input validation and buffer overflow prevention in embedded systems code

• Conducted security assessments and penetration testing ...read more

Preparation of embedded systems involves designing and integrating hardware and software components for specific applications.

• Identify the requirements and constraints of the embedded system

• Select appropriate hardware components such as microcontrollers, sensors, and actuators

• Design the software architecture including real-time operating systems and communication protocols

• Integrate hardware and software components to meet the system requirements

• Test and debug the embedded sys...read more

Embedded systems are computer systems designed to perform specific tasks within a larger system.

• Embedded systems are often used in devices such as medical equipment, automobiles, and home appliances.

• They typically have limited processing power and memory compared to general-purpose computers.

• They are designed to be reliable and efficient, often running on low-power processors.

• Programming languages commonly used for embedded systems include C and assembly language.

• Embedded sys...read more

ADC stands for Analog-to-Digital Converter, used in embedded systems to convert analog signals to digital data for processing.

• ADC is essential in embedded systems for converting real-world signals (such as temperature, light, sound) into digital data that can be processed by the microcontroller.

• ADC resolution determines the number of bits used to represent the analog signal digitally. Higher resolution means more accurate conversion.

• Sampling rate of ADC determines how often t...read more

SPI and I2C are two different communication protocols used in electronics.

• SPI stands for Serial Peripheral Interface and is a synchronous communication protocol.

• I2C stands for Inter-Integrated Circuit and is a synchronous communication protocol.

• SPI uses four wires for communication while I2C uses only two wires.

• SPI is faster than I2C but requires more pins.

• I2C is better suited for communication between multiple devices on the same bus.

• Examples of devices that use SPI include ...read more

Stack memory in microcontrollers is used for storing local variables, function parameters, return addresses, and other temporary data during program execution.

• Stack memory is a limited resource in microcontrollers and is typically smaller than heap memory.

• Stack memory is managed automatically by the compiler and is organized as a LIFO (Last In, First Out) data structure.

• Accessing stack memory is faster than accessing heap memory due to its linear allocation and deallocation p...read more

The embedded software development cycle involves designing, coding, testing, and debugging software for embedded systems.

• Designing: Planning the software architecture and functionality.

• Coding: Writing the actual code for the embedded system.

• Testing: Verifying that the software meets requirements and functions correctly.

• Debugging: Identifying and fixing any issues or bugs in the software.

• Examples: Developing firmware for a microcontroller, creating software for an IoT device.

Blinking an LED using bare metal code involves directly manipulating hardware registers without an operating system.

• Access the GPIO register for the specific pin connected to the LED

• Set the pin as an output

• Toggle the pin state at regular intervals to create the blinking effect

A vehicle tracking system in a microcontroller involves using GPS technology to track the location of a vehicle in real-time.

• Utilize GPS module to receive location data

• Store and process location data in microcontroller

• Transmit location data to a central server for monitoring

• Implement power management techniques to optimize battery usage

Volatile keyword prevents compiler optimization by telling the compiler that the variable's value can change unexpectedly.

• Volatile keyword is used to indicate that a variable may be changed unexpectedly, such as in the case of hardware registers.

• When initializing GPIO pins, using volatile keyword ensures that the compiler does not optimize away the initialization code.

• Without volatile keyword, the compiler may optimize out the GPIO initialization code if it thinks the value w...read more

Configuring a frequency input pin in MCAL and its flow till application layer

• Frequency input pin is configured in MCAL using configuration tools like AUTOSAR

• MCAL provides low-level drivers for hardware access

• The configured pin is then used by the HAL layer to provide higher-level drivers

• The application layer uses the HAL drivers to access the pin for frequency measurement

• The flow involves configuration, driver generation, and application usage

The I2C slave device holds the SCL line while processing and replying to messages.

• This is a common behavior of I2C slave devices.

• The slave device may hold the SCL line low or high depending on the implementation.

• This can cause issues with the I2C bus if not properly managed.

• The master device should wait for the slave device to release the SCL line before continuing communication.

Coding of micro involves writing and testing code for microcontrollers or microprocessors.

• Coding of micro involves writing instructions in a programming language such as C or assembly language.

• Testing the code involves simulating the behavior of the microcontroller or microprocessor to ensure it functions correctly.

• Examples of microcontrollers include Arduino, Raspberry Pi, and PIC microcontrollers.

Microprocessors are general-purpose CPUs while microcontrollers are specialized for specific tasks.

• Microprocessors are used in computers, smartphones, and other devices that require general-purpose computing.

• Microcontrollers are used in embedded systems, such as home appliances, automotive systems, and medical devices.

• Microprocessors typically have more processing power and memory than microcontrollers.

• Microcontrollers often have built-in peripherals, such as timers, ADCs, an...read more

Microcontrollers are small computers on a single integrated circuit used to control electronic devices.

• Microcontrollers are designed for specific tasks and are often used in embedded systems.

• They typically have on-board memory, input/output peripherals, and a central processing unit.

• Examples include Arduino, Raspberry Pi, and PIC microcontrollers.

PLC is a specialized computer for industrial control while microcontroller is a small computer on a single integrated circuit.

• PLC is designed for industrial automation and control systems while microcontroller is used in various applications such as consumer electronics, automotive, and medical devices.

• PLC has a fixed set of inputs and outputs while microcontroller can be programmed to interface with various sensors and actuators.

• PLC is programmed using ladder logic or other ...read more

Timers in microprocessors vary in features and implementation.

• Timers can be used for various purposes such as generating interrupts, measuring time intervals, and controlling PWM signals.

• Different microprocessors may have different types of timers such as basic timers, general-purpose timers, and advanced timers.

• The number of timers, their resolution, and clock source can also vary between microprocessors.

• Examples of microprocessors with different timer features include STM32...read more

Communication between subsystems involved using MQTT protocol and WiFi connections.

• Used MQTT protocol for lightweight messaging between devices

• Established WiFi connections for data transfer

• Implemented custom communication protocols for specific tasks

• Utilized serial communication for direct communication between Arduino and RPi

Microprocessors are general-purpose processors while microcontrollers are specialized processors for specific tasks.

• Microprocessors are used in computers and smartphones, while microcontrollers are used in embedded systems like washing machines and traffic lights.

• Microprocessors have separate memory and I/O devices, while microcontrollers have integrated memory, I/O ports, and peripherals.

• Microprocessors require external components for operation, while microcontrollers are se...read more

SPI (Serial Peripheral Interface) is a communication protocol commonly used in embedded systems for communication between microcontrollers and peripheral devices.

• SPI is a synchronous serial communication protocol where data is transferred between a master device and one or more slave devices.

• It uses four communication lines: MOSI (Master Out Slave In), MISO (Master In Slave Out), SCK (Serial Clock), and SS (Slave Select).

• SPI is commonly used in projects involving sensors, dis...read more

A microcontroller is a small computer on a single integrated circuit that is designed to control specific devices.

• It contains a CPU, memory, and input/output peripherals on a single chip

• Used in embedded systems, robotics, and automation

• Examples include Arduino, Raspberry Pi, and PIC microcontrollers

A microcontroller is a small computer on a single integrated circuit that contains a processor core, memory, and programmable input/output peripherals.

• Microcontrollers are used in embedded systems for controlling various devices and processes.

• They are commonly found in everyday devices such as microwave ovens, washing machines, and remote controls.

• Microcontrollers are programmed using specialized software tools and languages like C or assembly language.

• They are designed to be...read more

A microcontroller is a small computer on a single integrated circuit that contains a processor core, memory, and programmable input/output peripherals.

• Microcontrollers are used in embedded systems for controlling devices or processes.

• They are often programmed using a high-level language like C or assembly.

• Common microcontroller manufacturers include Atmel, Microchip, and Texas Instruments.