Microcontroller Interview Questions and Answers

This article presents a collection of microcontroller interview questions and answers compiled by experts in the field of embedded systems. This guide aims to help candidates successfully navigate job interviews for various microcontroller-related positions, including hardware and programming roles. These questions are also valuable for preparing for college viva examinations.

Question -1: Explain interfacing of microcontroller with External EPROM device.

Answer -1: Questions related to interfacing microcontrollers with external memory devices like EPROM, ROM, or serial communication devices are commonly asked, especially for hardware-focused positions.

Question -2: Explain Serial communication flags and registers used in microcontroller.

Answer -2: SCON, SBUF, TI, and RI are essential registers and flags used in serial communication with microcontrollers. Consult resources on microcontroller serial communication for a detailed explanation.

Question -3: What is the difference between timer and counter of microcontroller?

Answer -3: A timer counts internal clock cycles, providing a time base. A counter, on the other hand, counts external events or pulses. See resources on microcontroller timers for further details.

Question -4: Explain internal architecture of 8051 microcontroller.

Answer -4: This question assesses your understanding of the internal modules (blocks) within a microcontroller and their respective roles in various microcontroller applications. Review resources on microcontroller architecture.

Question -5: Write a simple microcontroller program to blink LED at the interval of 10 seconds.

Answer -5: Consult resources on microcontroller programming for examples and explanations on how to accomplish this task.

Question -6: What is the difference between microcontroller and microprocessor?

Answer -6: While microcontrollers and microprocessors share similarities, key distinctions exist. Microcontrollers are primarily used in monitor and control applications, integrating CPU, timers, and I/O ports on a single chip. Microprocessors, conversely, are often employed in embedded signal processing and general computing tasks and typically only contain the CPU. In essence, the microcontroller is an integrated system, whereas the microprocessor is only a CPU. See resources on Microcontroller vs Microprocessor for further details.

Question -7: Explain SPI and CAN interfaces used with Microcontroller.

Answer -7: Explore resources detailing the CAN interface and the SPI interface to understand their functionalities and applications in microcontroller systems.

Question -8: Mention any one 32 bit microcontroller and explain the same.

Answer -8: Several microcontrollers support a 32-bit architecture. Freescale (now NXP) is one example. Consult resources on 32-bit microcontrollers for more information.

Question -9: Explain the difference between microcontroller C programming and assembly level programming.

Answer -9: Address the advantages and disadvantages of each approach. For instance, C programming offers higher-level abstraction and portability, while assembly programming provides finer control over hardware and potentially better performance. Also, explain that assembly code routines can be integrated within C programs if necessary.

Question - 10 : Explain data types used in microcontroller programming.

Answer -10: Describe the common data types used in microcontroller programming, including bit, sbit, sfr, float, signed char, unsigned char, enum, and signed int. For each type, be prepared to specify its storage size (in bits or bytes) and the range of values it can represent if asked.

These microcontroller interview questions and answers are designed to assist engineers preparing for interviews for diverse roles, including microcontroller programmers (both senior and junior levels) and positions related to microcontroller-based board interfacing.