Bringing the hidden world of a microprocessor to real life

Is it possible to touch the internal components of a microchip?

Dr. P. Papazoglou combines imagination, art, and engineering to create unique educational tools and demystify complex topics in academic classes.

Prof. P. Papazoglou is also an active hardware/software designer/developer and his interests are in the areas of immersive technologies for transforming the existing conventional approaches in education.

Begin your journey with version 1 of the hardware-oriented microprocessor simulator and explore a fully functional device where students can interact with and program the internal components of an experimental microprocessor.

Version 1 was presented at the IEEE EDUCON2024 conference in May 2024.

Version 2 is under construction.

Explore an innovative tool for learning microprocessors:

Microprocessor Simulator (HOMS)

Open-Source Project

  • A full-working hardware-oriented simulator
  • Microprocessor/ Microcomputer simulator
  • Educational tool
  • Based on Arduino platform
  • Easy reproduction
  • Custom educational scenarios
  • Suitable for academic teachers and researchers in the field of engineering education

View License

Every internal component of the microprocessor
is implemented as a physical 3D-constructed object

  • General Purpose Registers (GPR)
  • Special Purpose Registers (SPR)
  • Arithmetic & Logic Unit (ALU) / SR
  • Control Unit (CU)
  • Memory - I/O System
Autonomous operation

  • The HOMS system does not require a computer because it operates autonomously.
  • Program instructions are entered directly into the memory unit using switches and buttons.
  • The user inputs the code bytes representing the supported assembly instructions directly into the memory system.
  • The memory addresses are 8 bits long, as is the memory location capacity.
  • Each address or memory content is formed by eight switches that represent 8 bits (=1 byte).
  • The control unit (CU) fetches instruction codes and data from this unit.
  • Alternatively, the instructions code can be set directly from the embedded program to avoid manual storage.

Unique features

Customizable architecture

The teacher or student can use any number or type of blocks for building the preferred microprocessor architecture.

Block reusability

The microprocessor units are based on the same board and the embedded software determines the block functionality.

Programmable functionality

Based on the embedded software, a block operates like a register or control unit or ALU or special register, etc.

Experimental architecture

Based on the number and type of blocks, a teacher or student can test a prototype architecture or to expand an operation to smaller steps by using more blocks.

Assembly instructions development

Programmer/user, Software/hardware developer, Watching/studying

Hardware point of view

The HOMS tool, emphasizes the hardware layer which is hidden in the existing simulation tools. Thus the “connection” of instruction, operation and hardware implementation is more clear in the student’s minds

Multiple points of view

The HOMS user is free to build any assembly instruction which is supported by the software inside control unit.

Educational scenarios

Using the default HOMS tool architecture, teachers can develop the desired assembly instructions for building different educational scenarios.

Standalone tool

The proposed HOMS tool does not need a PC and can be operated autonomously. Thus, constitutes a mobile laboratory system unit

Easy reproduction

The hardware components of the HOMS tool can be found easily in any market. On the other hand, the multiple identical blocks support easily the reproduction procedure

Open features

The main advantage of the implemented HOMS tool is the object-oriented approach and the open-source hardware which gives the freedom to any developer not only to reproduce the same tool but also to implement the whole simulator using different blocks (with or without an LCD, buttons, etc). Note that the embedded software makes the difference.

Full Demo

Short Demo


View/Download files

HOMS complete technical reference

General information, System description,System operation, Build reference (71 pages). View (PDF)

HOMS Quick user guide

System map, Memory unit operation, Data entry, Code preload. View (PDF)

Arduino (.ino) files

Arithmetic & Logic (ALU) Unit/SR, Control Unit (CU), Memory & I/O System, Registers, 7SD test. Download (ZIP)


Blocks A,B,C,D and System.
View all blocks-full (PDF)
View Block-A online (GPR/SPR)
View Block-B online (ALU/SR)
View Block-C online (CU)
View Block-D online (MEM-I/O)

System physical dimensions

Components, materials, circuits, etc. View (PDF)

License & Time stamp

This is an open-source project under a CC license. This project has been also time stamped by HELLENIC COPYRIGHT ORGANIZATION (Date and time: 23/02/2024 22:57:22, Registration 5211). View license in TXT file or View license online

IEEE EDUCON 2024 Presentation

Version 1 was presented at the IEEE EDUCON2024 conference in May 2024.View file (PDF) || EDUCON 2024 on web

Selected publication (Prev. Work)

P.M.Papazoglou, A Hybrid Simulation Platform for Learning Microprocessors, Computer Applications in Engineering Education, 10.1002/cae.21921, (pp 655-674) WILEY, 2018 online

Associate Professor Dr. Panayotis (Panos) Papazoglou

National and Kapodistrian University of Athens (NKUA)
Dept. of Digital Arts and Cinema

contact: papaz [at] uoa [dot] gr

Copyright © Dr. Panayotis (Panos) Papazoglou & National and Kapodistrian University of Athens (NKUA)

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