10+ Senior Embedded Engineer Interview Questions and Answers

A while loop checks the condition before executing the code block, while a do while loop executes the code block once before checking the condition.

• While loop: Condition is checked before entering the loop.

• Do while loop: Code block is executed at least once before checking the condition.

• Example: while (condition) { // code block } vs. do { // code block } while (condition);

C program for finding greatest of 3 numbers and finding a number in a string. RTOs related questions.

• For finding greatest of 3 numbers, use if-else statements and compare each number with the other two.

• For finding a number in a string, use string manipulation functions like strstr() or atoi().

• For RTOs related questions, brush up on traffic rules and regulations specific to your region.

Embedded C programming is a specialized skill used in developing software for embedded systems.

• Embedded C is a variant of the C programming language specifically designed for embedded systems.

• It is used to write code for microcontrollers, sensors, and other hardware devices.

• Embedded C programming requires knowledge of low-level hardware interactions and memory management.

• Example: Writing code to control a robotic arm using a microcontroller.

Calculate size of variable without library function

• Use the sizeof operator to calculate the size of a variable

• Multiply the size by the number of elements if it's an array

• Size of a struct is the sum of sizes of its members

• Size of a union is the size of its largest member

• Size of a pointer is platform-dependent

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

DMA stands for Direct Memory Access, a feature that allows hardware devices to transfer data to/from memory without involving the CPU.

• DMA is used to offload data transfer tasks from the CPU, improving overall system performance.

• Context switching is the process of saving and restoring the state of a CPU so that multiple processes can share the same CPU.

• DMA and context switching are both important concepts in embedded systems design.

• Example: In a system with a network interface...read more

Pipeline in ARM is a technique used to increase the performance of the processor by overlapping the execution of multiple instructions.

• Pipeline allows multiple instructions to be processed simultaneously in different stages of execution.

• It helps in reducing the overall execution time of a program.

• ARM processors typically have a 3-stage pipeline, but some newer designs have more stages for better performance.

• Example: In a 3-stage pipeline, the fetch, decode, and execute stages...read more

Processes are independent units of execution while threads are lightweight subunits of a process sharing resources.

• Processes are independent units of execution with their own memory space and resources.

• Threads are lightweight subunits of a process sharing the same memory space and resources.

• Processes have their own program counter, registers, and stack while threads share these.

• Example: A web browser running multiple tabs as processes, each tab having multiple threads for ren...read more

Interrupt handling is a mechanism to handle asynchronous events in real-time systems.

• Interrupts are signals generated by hardware or software to interrupt the normal execution of a program.

• Interrupts are prioritized and handled by the Interrupt Service Routine (ISR).

• ISR saves the current state of the processor, executes the interrupt handler code, and restores the saved state.

• Interrupts can be edge-triggered or level-triggered, and can be handled synchronously or asynchronous...read more

Compilation process in C involves preprocessing, compiling, assembling, and linking.

• Preprocessing: Includes header files, macro expansion, and conditional compilation.

• Compiling: Translates source code into assembly code specific to the target architecture.

• Assembling: Converts assembly code into machine code in object files.

• Linking: Combines object files and libraries to generate an executable file.

Storage classes in C determine the scope and lifetime of variables.

• Auto: default storage class for local variables

• Static: retains value between function calls

• Extern: used to declare variables in other files

• Register: stores variables in CPU registers for faster access