10+ Embedded Developer Interview Questions and Answers for Freshers

A null pointer points to nothing while a void pointer can point to any data type.

• A null pointer is a pointer that has been explicitly set to a null value.

• A void pointer is a pointer that has no type associated with it.

• A null pointer is a subtype of a void pointer.

• A null pointer is used to indicate that a pointer does not point to a valid object.

• A void pointer is used to store a pointer to any type of object.

Storage class specifiers in C are used to define the scope and lifetime of variables.

• There are four storage class specifiers in C: auto, register, static, and extern.

• Auto variables are local to a block and have automatic storage duration.

• Register variables are stored in CPU registers for faster access.

• Static variables have a lifetime throughout the program and are initialized only once.

• Extern variables are declared in one file and can be used in other files.

• Storage class spec...read more

Preprocessor in C is a tool that processes source code before compilation.

• It performs macro substitution

• It includes header files

• It conditionally compiles code

• It defines constants and symbols

• It removes comments

• Examples of preprocessor directives are #include, #define, #ifdef, #ifndef, #endif

• Preprocessor directives start with a # symbol

Kernel space is a protected area of memory where the core of the operating system resides. Device drivers are software that allows the operating system to communicate with hardware devices.

• Kernel space is a privileged area of memory that is reserved for the core components of the operating system.

• Device drivers are software modules that facilitate communication between the operating system and hardware devices.

• Experience in device drivers may involve writing, debugging, or op...read more

An Interrupt Service Routine (ISR) is a function that is executed in response to an interrupt signal.

• ISR is a type of callback function that handles interrupts

• It is a low-level function that runs in response to a hardware event

• ISR must be short and fast to avoid blocking other interrupts

• Examples of interrupts include keyboard input, timer events, and hardware errors

SPI, UART, and I2C are communication serial protocols used in embedded systems to transfer data between devices.

• SPI (Serial Peripheral Interface) is a full-duplex synchronous communication protocol commonly used for communication between microcontrollers and peripheral devices.

• UART (Universal Asynchronous Receiver/Transmitter) is a serial communication protocol that uses two wires for data transmission and is commonly used for communication between devices over longer distanc...read more

ARM Cortex-M series controllers have a register level architecture for low-level programming and control.

• ARM Cortex-M series controllers have multiple registers for controlling various functions such as GPIO, timers, and interrupts.

• Registers are memory locations within the processor used for storing data and control information.

• Programmers can directly access and manipulate these registers to configure the behavior of the controller.

• For example, the GPIO registers can be used...read more

Program to implement matrix multiplication in C++.

• Declare two matrices A and B of appropriate dimensions.

• Initialize the matrices with values.

• Create a result matrix C with dimensions rows of A and columns of B.

• Perform matrix multiplication using nested loops.

• Print the result matrix C.

An ultrasonic sensor is a device that uses sound waves to measure distance and detect objects.

• Uses high frequency sound waves to bounce off objects and measure distance

• Commonly used in robotics and automation for object detection and avoidance

• Can also be used in parking sensors, security systems, and medical imaging

• Works by emitting a sound wave and measuring the time it takes for the wave to bounce back

OS boot up sequence involves several steps such as BIOS initialization, bootloader loading, kernel loading, and initialization of system services.

• BIOS (Basic Input/Output System) initialization

• Bootloader loading (e.g. GRUB, LILO)

• Kernel loading and initialization

• Init process execution

• System services initialization

I am expecting a competitive salary based on my skills and experience.

• I am open to negotiation based on the job requirements and responsibilities.

• I am looking for a salary that is in line with industry standards.

• I am willing to discuss benefits and other compensation packages.

• I am not comfortable sharing my current salary as it is confidential.

• I am looking for a long-term career opportunity with growth potential.

Sensors are devices that detect and respond to physical stimuli.

• Temperature sensors (thermocouples, RTDs, thermistors)

• Pressure sensors (piezoresistive, capacitive, piezoelectric)

• Motion sensors (accelerometers, gyroscopes, magnetometers)

• Light sensors (photodiodes, phototransistors, photovoltaic cells)

• Gas sensors (carbon monoxide, oxygen, carbon dioxide)

• Humidity sensors (capacitive, resistive)

• Proximity sensors (inductive, capacitive, ultrasonic)

The question is asking for code in the C language.

• Use the 'C' programming language syntax to write the code.

• Include necessary libraries and headers.

• Provide a clear and concise solution to the problem.

• Test the code thoroughly before submission.