SmartCube

SmartCube is a tiny and customizable desk toy using the ESP8266 D1 Mini. Built entirely from cheap, easy-to-find parts, it can connect to Wi-Fi and can be programmed to do just about anything: show notifications, display the weather, monitor stuff, show a clock, serve a web site, be a virtual pet or whatever else your caffeine-fueled brain can imagine.

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Info

• This is a hobby project I work on and develop for when I have literally nothing else to do, do not expect regular updates. You are free to clone this and do whatever you like with it
• Code: I have a few projects developed for the Cube. You can see the list here on my Gitea
• V2: There is also a more powerful version, it's pretty much the same but with extra features and is using ESP32, I only made one of them and I don't like it yet, it needs work.
• Case: 3D-printable design included in /hardware directory
• Schematics: and assembly instructions are also in the /hardware directory

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Bill of Materials

Component	Quantity	Description	Notes
ESP8266 D1 Mini	1	Microcontroller module
SSD1306 OLED Display	1	128x64 resolution, I2C interface
14250 Rechargeable Battery	1	Lithium-ion battery	Make sure you get the rechargeable type, most 14250 are not
TP4056 Module	1	Charging and protection circuit	Does not need to have a USB connector
6x6 Push Buttons	3 or 4	Tactile push buttons
20mm Piezo Buzzer	1	Caseless buzzer for audio
Resistors (10kΩ)	3 or 4	Pull-down resistors for buttons	Not reqired if you are using ESP32
Wires	Several	Thin wires for connections
Enclosure	1	3D-printed case	3D printable STL files are in hardware/case/
2x6mm screw	12	Small screws for seembling the case	Does not have to be exactly 6mm long

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Demo Code Explanation

This repository contains a basic "Hello, World!" project for the SmartCube.

Getting Started:

1. Download and install VSCode or VSCodium.
2. Install the PlatformIO IDE extension.
3. Clone this repository and open the project folder in VSCode/VSCodium.
4. PlatformIO will automatically handle environment setup and dependencies when you open the project.

Project Structure:

All source code is located in the src/ directory. You should start by opening src/main.cpp, which contains the entry point and initialization logic.

What the Code Does:

This demo handles basic system functionality, including:

• System initialization
• Button input handling
• OLED display output configuration
• WiFi management

Key Features

1. WiFi Management:

   • The cubeWifiManager class manages WiFi connectivity seamlessly.
   • If no known WiFi network is available, it starts a configuration portal and creates an access point (AP), allowing users to connect the SmartCube to a network from another WiFi-enabled device.
   • The OLED display shows the access point details, such as the AP name and IP address, making the setup process very easy.

2. Button Handling:

   • Buttons are mapped to specific GPIO pins: PIN_BTN_L (Left), PIN_BTN_M (Middle), and PIN_BTN_R (Right).
   • The cubeButtonHandler function, executed in the loop(), monitors and interprets button presses, differentiating between short and long presses.

Default Button Actions

• Right Button:

  • Short Press: Turns the OLED display on (if previously off).
  • Long Press: Turns the OLED display off, helping conserve power.

• Left + Middle Buttons (Simultaneous Long Press):

  • Triggers an ESP8266 reboot, effectively restarting the device.

This is meant to provide a minimal starting point for further development with the SmartCube.

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Assembly Instructions

1. Push the ESP8266 microcontroller in the ledge on the bottom the cube body it sould 'click in' with the USB-C port facing the hole. Body with 3 or 4 button slots is available in the hardware/case/

2. Buttons: You can also glue in the buttons to the top slots at this step

3. OLED Display: Crew in or glue the SSD1306 to the front part of the cube solder the 4 wires to the OLED display, make sure you have some extra lenght, 4-5cm sould be more than enough

4. Buzzer: Glue in the buzzer to the back part of the cube

5. Solder all of the components to the microcontroller:

Pin Connections

Pin numbers for buttons and other stuff is defined in the example config and the schematic for the D1 Mini is here:
You don't have to follow my pin definition exactly but I find this the easiest way to assemble and fit everything in. 3 Button variant is the standard. If you are gonna go with the 4 button variant you will need to define this yourself.

• Button Left (PIN_BTN_L): GPIO12
• Button Middle (PIN_BTN_M): GPIO13
• Button Right (PIN_BTN_R): GPIO15
• Piezo Buzzer (PIN_BUZZER): GPIO0

The OLED display must to be connected via I2C on pins:

• SDA: D2 (GPIO4)
• SCL: D1 (GPIO5)
• GND: GND
• VCC: 3.3V pin or directly to the TP4056 output

6. Power Supply Setup:
   • Battery is not required and you can skip this step if you want to but it is much cuter when it's portable. A single 600mAh 14250 lasts about 24 hours.
   • Solder the 14250 battery to the TP4056 module input pins.
   • Wire the output of the TP4056 to the 3.3V pin on the D1 Mini to power the device.
   • Connect the 5V output pin from the D1 Mini to the input port on the TP4056 module to allow charging trough the Data USB port on the ESP8266.

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Notes

• This is still a work in progress

• Everything is pretty tightly packed in there and it's a mess. But it's not as hard to make as it looks.

• Ensure all connections are secure. Hot glue is your friend.

• Test the circuit thoroughly before placing and glueing it in the enclosure.

• Battery is the trickiest part to fit in, it's best to glue the charging module directly to it and put it in the case last

For questions or additional details, feel free to reach out! I would love to hear some feedback. Good luck and have fun :)