Week 8 - Journal

Smart Mood Display Circuit 

This week's assignment required us Build a simple smart circuit that contains at least TWO action components that you can control wirelessly.

This project involves designing a smart circuit that displays the user's mood using two action components:

1. An LCD screen – Displays a mood-related message (e.g., "Happy 😊", "Sad 😔", "Excited 🎉").

2. An RGB LED – Changes color to match the displayed mood (e.g., blue for sad, green for calm, red for excited).

The circuit is wirelessly controlled, allowing the user to update their mood remotely via a smartphone app, a web interface, or a Bluetooth module.

Inspiration

The idea for this project was suggested by a friend, which inspired the development of a simple yet engaging way to express emotions through a visual and interactive display.

Input Components:

• Bluetooth module : will allow you to control the LCD and RGB LED wirelessly from a smartphone or computer. 

Output Components:

• LCD: Displays a message when the ultrasonic sensor detects a specific distance.

• RGB : change the color and control it by phone 

Microcontroller:

• Arduino Uno: Controls the entire circuit.

firtizing Simulation:

I used firtizing to test the circuit before building it physically, ensuring that no components would be damaged. I chose Fritzing over Tinkercad because:

• It provides a wider range of components that Tinkercad does not have.

• It allows for a more detailed and realistic simulation of the circuit.

Steps:

1. Inserting Components:

   • I added the required components, including a breadboard, Arduino Uno, Bluetooth module ,RGB led , LCD

2. Wiring the Power Connections:

   • Connected VCC (5V) from the Arduino to the positive rail of the breadboard.

   • Connected GND from the Arduino to the negative rail of the breadboard.

3. Bluetooth Wiring:

   • VCC → Positive rail

   • GND → Negative rail

   • RX pin : to TX pin in arduino  

   • TX pin : to RX pin in arduino  

4. LCD Wiring (4 Pins):

   • VCC → Positive rail

   • GND → Negative rail

   • SDA → Pin A4 on the Arduino

   • SCL → Pin A5 on the Arduino

5. RGB 

   • Red Pin → Pin A0 (Arduino)

   • green Pin → Pin A1(Arduino)

   • GND → Negative rail

1) Issue: Missing Bluetooth Module and LCD in Fritzing Simulation

I couldn't find the Bluetooth module and LCD in Fritzing for simulation.

Solution:

I asked a friend, and he told me that I could download them as FZZ files and import them into Fritzing.

2) Issue: LCD Not Working Properly

After testing, I discovered that the issue was related to the code and the LCD model I was using.

Solution:

I searched in the Arduino Hub and found the correct library: LiquidCrystal_I2C. To ensure proper communication, I also added the Wire.h library.

Ref 1 ( iquidCrystal-i2c)

https://forum.arduino.cc/t/i2c-lcd-module-using-wire-h/1153363/5 

Ref 2 ( Wire.h)

https://forum.arduino.cc/t/wire-h-library-and-lcd-i2c/202480