The Top 10 Embedded system interview questions and answers that potential hiring managers ask you during an interview to determine if you’re the right fit for the role.
Question 1. Explain what is embedded system is in a computer system?
Answer. An embedded system is a computer system that is part of a larger system or machine. It is a system with a dedicated function within a larger electrical or mechanical system.
Question 2. Mention what are the essential components of an embedded system?
Answer. Essential components of the embedded system include.
- Hardware
Processor.
Memory.
Timers.
- I/O circuits.
System application-specific circuits.
- Software.
It ensures the availability of System Memory.
It checks the Processor Speed availability.
The need to limit power lost when running the system continuously.
- Real-Time Operating System.
It runs a process as per scheduling and does the switching from one process to another.
Question 3. Why the embedded system is useful?
Answer. The embedded system is useful because, with an embedded system, it is possible to replace dozens or even more of hardware logic gates, input buffers, timing circuits, output drivers, etc. with a relatively cheap microprocessor.
Question 4. Explain what are real-time embedded systems?
Answer. Real-time embedded systems are computer systems that monitor, respond or control an external environment. This environment is connected to the computer system through actuators, sensors, and other input-output interfaces.
Question 5. Mention the difference between microprocessor and microcontroller?
Answer. The microprocessor is the manager of the resources (I/O, memory) which lie outside of its architecture Microcontroller have I/O, memory, etc. built into it and is specifically designed for control
Question 6. Explain what is interrupt latency? How can you reduce it?
Answer. Interrupt latency is the time taken to return from the interrupt service routine post handling a specific interrupt. By writing minor ISR routines, interrupt latency can be reduced.
Question 7. Mention what are buses used for communication in embedded systems?
Answer. For an embedded system, the buses used for communication include.
- I2C: It is used for communication between multiple ICs.
- CAN: It is used in automobiles with centrally controlled networks.
- USB: It is used for communication between CPU and devices like mice, etc. While ISA, EISA, PCI are standard buses for parallel communication used in PCs, computer network devices, etc.
Question 8. Explain what is the need for an infinite loop in embedded systems?
Answer. Embedded systems require infinite loops for repeatedly processing or monitoring the state of the program. For instance, the case of a program state continuously being verified for any exceptional errors that might just happen during run-time such as memory outage or divide by zero, etc.
Question 9. Explain what is semaphore?
Answer. A semaphore is an abstract data type or variable that is used for controlling access by multiple processes to a common resource in a concurrent system such as a multiprogramming operating system.
Semaphores are commonly used for two purposes
- To share a common memory space.
- To share access to files.
Question 10. List out some of the commonly found errors in Embedded Systems?
Answer. Some of the commonly found errors in embedded systems are.
- Damage of memory devices static discharges and transient current.
- Address line malfunctioning due to a short circuit.
- Data lines malfunctioning.
- Due to garbage or errors some memory locations being inaccessible in storage.
- Inappropriate insertion of memory devices into the memory slots.
- Wrong control signals.
