Binary to Decimal Converter using Arduino and OLED Display

In the world of computer engineering and digital electronics, "Binary" is like the native language machines use to communicate. However, for humans, understanding and calculating multi-digit binary numbers can often be challenging. This project is therefore designed to bridge the gap between digital systems and humans by creating an 8-bit binary (00000000 - 11111111) to decimal (0 - 255) converter that we are familiar with, using an Arduino board as the main processor.

This project shows how to convert a Binary number (Up to 8 Bits) into a Decimal number. The Binary number is fed to the Arduino through an 8x DIP Switch. Arduino then converts this Binary number to its Decimal equivalent. These numbers are displayed on an OLED Display and Serial Monitor.

---

Engineering Details and Key Components

In designing this system, we emphasized the accuracy of input reception and real-time display. Key components include:

1. Input Section: 8x DIP Switch

The DIP Switch acts as 8 channels of Digital Input. It simulates a 1-Byte "Register" in computer memory. Each switch represents a Bit, from the Least Significant Bit (LSB - $2^0$) to the Most Significant Bit (MSB - $2^7$).

• Engineering Note: In electronics, connecting a switch requires a Pull-up or Pull-down Resistor to prevent Floating conditions (unstable voltage). In this project, we can use Arduino's internal INPUT_PULLUP function to simplify the circuit.

2. Processing Section: Arduino Microcontroller

The Arduino board functions as the brain of the system. It scans the Logic State of all 8 Digital I/O pins connected to the DIP Switch. Then, it takes the read values (0 or 1) and calculates them according to binary mathematics.

3. Display Section: OLED Display (SSD1306)

We chose a small OLED display that communicates via the I2C (Inter-Integrated Circuit) protocol, which uses only 2 signal wires (SDA and SCL), thus saving Arduino pins and displaying clearer text than typical LCD screens.

---

Software Logic (Code Logic)

The core of this project is the algorithm for converting binary to decimal values, which operates as follows:

1. Bit Scanning: The program starts by reading values from the 8 Digital Pins connected to the DIP Switch, using the digitalRead() command within a loop or by reading an Array.
2. Binary to Decimal Calculation: Once the status of each bit is obtained, the program will use the "Positional Weighting" principle as follows: $$Decimal = \sum_{i=0}^{7} (Bit_i \times 2^i)$$ For example, if the DIP Switch is set to 10000001, the program will calculate: $(1 \times 2^7) + (0 \times 2^6) + ... + (0 \times 2^1) + (1 \times 2^0) = 128 + 1 = 129$
3. Real-time Update: To ensure smooth operation, the program continuously loops to scan values and update the OLED screen, as well as sending data to the Serial Monitor. This allows users to see changes in the decimal value immediately when flipping a switch.

Benefits and Further Applications

This project is not only a teaching tool for Digital Logic but also a foundation for creating custom configuration Input Interfaces in control engineering applications, such as setting addresses for sensors in RS-485 systems or initial password settings in other Embedded Systems. Understanding the connection between a Physical Switch and the Logic within a processor will help young engineers grasp the Low-level mechanisms of computer operation more deeply.