4-Bit Adder is an educational dashboard that allows interaction between user input and the illuminated graphics showing the descete logic required to make a 4-bit adder.

The LEDs change state depending on the user input and indicate the logic state of inputs and outputs of descrete components.

Users input two 4-bit numbers using toggle switches under the INPUT section. The COMPUTATION section shows the binary math. And, the RESULT section shows the resulting value represented as binary.

The 4-bit adder is the classic adder pattern using XORs, ANDs, and ORs.

The Legend shows XOR, AND, and OR truth tables and a binary to decimal conversion as an aid to help teach descrete logic and conversions.

The back reveals a wiring mess!

The LEDs of each adder section are held in place using a 3D printed bracket. And each LED is connected to a port of a I2C PCA9685 PWM driver.

In retrospect, it would of been easier to design a PCB for each section that would contain the LEDs, resistors, and a PCA9685 driver versus soldering everything by hand.

An Arduino Nano (Atmega328p) was used due to very low computational requirements of the project.