Embedded Systems Interview Questions

This page features a curated list of embedded systems interview questions, selected from our free technical book, Circuits and Code. Whether you’re preparing for an embedded systems job interview or refreshing your knowledge in areas like firmware development, electrical engineering, or real-time systems, these questions cover essential topics for embedded system engineers.

You can find detailed answers and explanations in the full book, available on our download page.

Topics Covered

The questions cover topics such as:

• Embedded C fundamentals
• Microcontroller architecture
• RTOS concepts
• Communication protocols (I2C, SPI, UART, CAN)
• Debugging and testing
• Power and performance optimization
• Real-world problem-solving

Embedded Systems Interview Questions

1. Implement a function to validate the parity of a bitstream.
2. How would you sense the voltage of a battery with a microcontroller?
3. What is an interrupt service routine (ISR), and how do they differ from regular functions in implementation?
4. Draw a circuit to control a LED from a microcontroller GPIO pin.
5. Explain the following C keywords: volatile, const, and static.
6. What type of signal would be best for transferring data from a sensor located 1 meter away to a microcontroller?
7. Implement a PID controller in C and discuss its typical applications.
8. Compare and contrast I2C (Inter-Integrated Circuit) and SPI (Serial Peripheral Interface).
9. Implementing a bit-banged SPI master.
10. Describe how to use an oscilloscope to measure a signal.
11. Briefly describe Controller Area Network (CAN)?
12. Determine the step response of the following circuits.
13. Implement a C bytestream parsing function for a weather data sensor.
14. How would you sense how much current is flowing through a PCB to a load?
15. Given the following datasheet and code snippet, initialize the ADC and write a polling function to read the ADC voltage.
16. Given a 64-bit timer consisting of two 32-bit count registers, implement a function to get the 64-bit count.
17. Write a C function to determine the direction of stack growth on a system.
18. Solve the transfer function for the following circuit.
19. What are the differences between a mutex and a semaphore, and in what use cases are each typically employed?
20. When would you use a buck converter or a low dropout regulator?