8051 Microcontroller Notes and Study Material PDF Free Download

8051 Microcontroller Notes: Microcontrollers, also known as embedded controllers or embedded systems, are essential in the field of electronics. 8051 Microcontrollers are an important part of the Microprocessors and Microcontrollers (MPMC) course and this topic has a lot of scope as an individual subject as well. Students can refer to the Big Data Lecture Notes For CSE as per the latest and updated syllabus from this article.

For electronics, it is important to have great study materials to be able to do well in exams. Understanding this, we have put together 8051 Microcontroller Notes, along with several other useful references. The more study materials we have for our use, the better we understand the topics at hand. To further add to this, the better our understanding of the topics at hand, the better we are able to fare in our exams.

Listed below are the various study materials we have provided for 8051 Microcontroller in the following article.

Introduction to 8051 Microcontroller Notes – Free PDF Download

To learn about and to understand 8051 Microcontroller, we need to pay good attention in our electronics classes. It is also important to be taking adequate notes while sitting through classes. However, sometimes it may be that we are not able to do this. Maybe our mind is focused elsewhere or maybe we were just having a hard time understanding the topic at hand. In a situation like this, you need not worry, especially for 8051 Microcontrollers.

You don’t need to worry about 8051 Microcontroller classes and examinations because we have provided a brilliant set of 8051 Microcontroller Notes for you below. See the list of 8051 Microcontroller Notes below and then make use of them to the ebay of your abilities during your exam preparation.

  • MC Notes – 8051 Microcontroller
  • 8051 Microcontroller – 8051m Notes
  • Lecture Notes for B.Tech 8051 Microcontroller
  • Microcontroller Notes
  • Microcontrollers 8051 Notes

B.Tech 8051 Microcontroller Notes for Free Downloads

Microcontrollers, which are also called embedded systems or embedded controllers, are imperative to devices. They follow the I/O (input/output) relation, where the input for the controller is put in by the user, and the output is produced by the controller. Each microcontroller has a specific function in a machine which it carries out through the I/O feature. Microcontrollers also consist of a processor and memory, to add to the I/O function.

The 8051 Microcontroller was designed in the year 1981 by the company Intel and is also called the Intel MCS-51. It has several pragmatic and good features, which are listed as follows:

  • 8-bit microcontroller
  • Built with 40 pins DIP
  • ROM storage of 4KB
  • RAM storage of 128 bytes
  • 4 parallel 8-bit ports
  • 2 timers of 16-bits

The 8051 Microcontroller is one microcontroller which is commonly used in various fields and devices created for those fields. This microcontroller holds immense importance in the field of electronics, and thus is necessary to learn about, rather than just learning the basics of other microcontrollers.

8051 Microcontroller Reference Books

Every student has his or her strong points as well as his or her weaker points. What it comes down to is focusing on strengthening the weaker points while keeping the strong points steady as they are. Reference books will help a student understand better what he or she could not, because it is filled with information such as the applications, concepts and even case studies of all the topics of study at hand.

8051 Microcontroller is also such a subject where the student may face such problems. Some topics may be more difficult for some students, while the same topics will be simpler for other students to learn. Thus comes the need to focus on 8051 Microcontroller reference books.

Some 8051 Microcontroller reference books which would be of good use to students studying this microcontroller are contained in the list which follows.

  • 8051 Microcontroller – Kenneth Ayala
  • The 8051 Microcontroller: A Systems Approach – JG Mazidi, MA Mazidi, and RD McKinlay
  • The 8051 Microcontroller – I. Scott Mackenzie
  • 8051 Microcontrollers: an Applications Based Introduction – Calcutt, Cowan, Parchizadeh
  • Programming and Interfacing the 8051 Microcontroller – Ashutosh Ahluwahlia

8051 Microcontroller Curriculum

A curriculum is the skeleton or outline for any subject. It allows the student to scour through the list of topics that make up a subject, and scout the weak and strong points in them which we mentioned about earlier. It is severely important to have an idea of what is easier to study and what is not, relatively speaking. The curriculum for a subject will allow you to do this.

The 8051 Microcontroller curriculum also serves the same purpose, of helping students try to figure out what is tougher and what is relatively easier. Additionally, when the 8051 Microcontroller curriculum is right in front of an electronics student, it makes sure that he or she misses out on no topic at all.

Below is the unit wise and topic wise breakdown of the 8051 Microcontroller curriculum.

Module Topics
Module I: 8051 Microcontroller
  • Microprocessor vs microcontroller
  • Embedded systems
  • Embedded microcontrollers
  • 8051 Architecture
    • Registers
    • Pin diagram
    • I/O ports functions
    • Internal Memory organization
  • External Memory (ROM & RAM) interfacing.
Module II: 8051 Instruction Set
  • Addressing modes
  • Data transfer instructions
    • Arithmetic instructions
    • Logical instructions
    • Branch instructions
    • Bit manipulation instructions
  • Simple assembly language program examples (without loops) to use instructions
Module III: Stack, I/O Port Interfacing, Programming
  • 8051 stack
  • Stack and subroutine instructions
  • Assembly language program examples
    • Delay subroutine
  • Factorial of an 8 bit number (result maximum 8 bit)
  • Block move without overlap
  • Addition of N 8 bit numbers
  • Picking smallest/largest of N 8 bit numbers
  • Interfacing simple switch and LED to I/O ports to switch on/off LED with respect to switch status
Module IV: 8051 Timers and Serial Port
  • 8051 Timers and Counters
  • Operation and assembly language programming
    • Mode-1 and a square wave
    • Mode-2 on a port pin
  • 8051 Serial Communication
    • Basics of Serial Data Communication
    • RS-232 standard
    • 9 pin RS232 signals
  • Simple Serial Port programming in Assembly
  • C to transmit and receive data
Module V: 8051 Interrupts and Interfacing Applications
  • 8051 interrupts
  • 8051 assembly language programming
  • 8051 C programming
  • Interfacing 8051 to ADC-0804
  • LCD and stepper motor

List of 8051 Microcontroller Important Questions

The questions in the 8051 Microcontroller examination question paper are given module-wise. There are 10 questions (2 from each module) and the student must answer one question from each module worth 16 marks total. These questions can be either 4+6+6 marks, 8+4+4 marks, or 8+8 marks. All in all, there are 4 markers, 6 markers and 8 markers in the question paper to be answered.

4 Mark Questions

  1. What is a microcontroller and what are its applications?
  2. Write a program to move a block of data stores in external memory location 9000h to a location starting from F000h (without overlapping).
  3. Explain the role of CALL and subroutines in 8051 microcontroller programming.
  4. Explain RS-232 standards.
  5. Explain interrupt priority register of the 8051 microcontroller.

6 Mark Questions

  1. What are timers and counters? Explain the operations of the same.
  2. Explain timer control register and also timer mode control register.
  3. Explain the jump and CALL programme range with reference to 8051 microcontrollers.
  4. Write a programme to find the factorial of a number.
  5. Using a block diagram, explain the features of the 8051 microcontroller.

8 Mark Questions

  1. Using a functional block diagram, explain the architecture of 8051.
  2. Write instructions to add two BCD numbers and store the result in BCD register R, with reference to 8051.
  3. Write a programme to create a delay of 1 second, assuming that the oscillator frequency is 1.2 MHz.
  4. Write an 8051 C programme to send letters M, D and E to the LCD using delays.
  5. Explain the 8051 S-CON register.

FAQ’s about 8051 Microcontroller Notes

Question 1.
What are the applications of the 8051 Microcontroller?

The 8051 Microcontroller can be used to control various different kinds of devices, which include the following:

  • Automobiles
  • Medical sector
  • Railways sector
  • Aeronautics
  • Robotics
  • Spaceships and rockets (for space)
  • Light sensing
  • Temperature sensing
  • Process control devices
  • General consumer electronics

Question 2.
What is a good textbook or reference boom I can use to study 8051 Microcontroller?

A great book for studying the 8051 Microcontroller is “The 8051 Microcontroller: A Systems Approach” which is written by Janice Gillispie Mazidi, Muhammad Ali Mazidi, and Rolin D McKinlay. This is a great book as it has also been recommended by several professors for this subject in different universities as well.

Question 3.
What is the importance of the subject of the 8051 Microcontroller?

By the end of a course in the 8051 Microcontroller, students will have a fairly practical knowledge about this microcontroller. Students will have understood the architecture and programming of the 8051 Microcontroller along with several other aspects. This subject holds great importance because this microcontroller is used in several fields, and studying it would enable students to understand the working behind machinery and devices used throughout a vast array of industries and sectors.

Question 4.
What is the basic curriculum for the 8051 Microcontroller course?

There are a total of 5 modules in the 8051 Microcontroller curriculum, which are:

  • 8051 Microcontroller
  • 8051 Instruction Set
  • 8051 Stack, I/O Port Interfacing, Programming
  • 8051 Timers and Serial Port
  • 8051 Interrupts and Interfacing Applications


We have provided you some great 8051 Microcontroller Notes, reference books, curriculum and important questions. These should hopefully be adequate to help you study and attain the ebay marks possible in your 8051 Microcontroller paper. We wish all students good luck for the exams and hope that the study materials we have provided in the above article have taken away any anxiousness or nervousness felt by the student. It is our sincere hope that you as a student use these study materials and resources to the best of your abilities. Doing so will ensure that you get the greatest marks, in the process making you, your parents and your family happy. You will also be able to get a great job by doing well, so make sure to use the 8051 Microcontroller Notes wherever possible!