This guide will help you set up your ESP32 to serve the interactive solar system presentation with LED control functionality.

• ESP32 DevKit V1 (recommended) or similar
• USB cable for programming

• 8x LEDs (representing the 8 planets)
• 8x 220-330Ω resistors (current limiting resistors for LEDs)
• Breadboard or PCB
• Jumper wires
• Optional: LED holders or housings

• Mercury (Pin 2): White/Silver LED
• Venus (Pin 4): Yellow/Orange LED
• Earth (Pin 5): Blue LED
• Mars (Pin 18): Red LED
• Jupiter (Pin 19): Orange/Brown LED
• Saturn (Pin 21): Yellow LED
• Uranus (Pin 22): Light Blue/Cyan LED
• Neptune (Pin 23): Dark Blue LED

1. Install Arduino IDE (version 1.8.x or 2.x)

   • Download from: https://www.arduino.cc/en/software

2. Install ESP32 Board Package

   • Open Arduino IDE
   • Go to File → Preferences
   • In "Additional Board Manager URLs" add:

     https://dl.espressif.com/dl/package_esp32_index.json
     

   • Go to Tools → Board → Board Manager
   • Search for "ESP32" and install "ESP32 by Espressif Systems"

3. Install Required Libraries

   • Go to Tools → Manage Libraries
   • Install the following libraries:
     • WebServer (usually comes with ESP32 package)
     • SPIFFS (usually comes with ESP32 package)
     • WiFi (usually comes with ESP32 package)

4. Install ESP32 SPIFFS Uploader Plugin

   • Download from: https://github.com/me-no-dev/arduino-esp32fs-plugin
   • Extract to your Arduino IDE tools folder:
     • Windows: C:\Users\{username}\Documents\Arduino\tools\ESP32FS\tool\esp32fs.jar
     • Mac: ~/Documents/Arduino/tools/ESP32FS/tool/esp32fs.jar
     • Linux: ~/Arduino/tools/ESP32FS/tool/esp32fs.jar
   • Restart Arduino IDE

ESP32 Pin    Component           Connection
=========    =========           ==========
3.3V         Breadboard          Positive rail
GND          Breadboard          Negative rail

Pin 2        LED 1 (Mercury)     Cathode via 220Ω resistor to GND
Pin 4        LED 2 (Venus)       Cathode via 220Ω resistor to GND  
Pin 5        LED 3 (Earth)       Cathode via 220Ω resistor to GND
Pin 18       LED 4 (Mars)        Cathode via 220Ω resistor to GND
Pin 19       LED 5 (Jupiter)     Cathode via 220Ω resistor to GND
Pin 21       LED 6 (Saturn)      Cathode via 220Ω resistor to GND
Pin 22       LED 7 (Uranus)      Cathode via 220Ω resistor to GND
Pin 23       LED 8 (Neptune)     Cathode via 220Ω resistor to GND

1. Power Rails: Connect ESP32 3.3V to breadboard positive rail, GND to negative rail

2. For Each LED:

   • Connect LED anode (+, longer leg) to ESP32 GPIO pin
   • Connect LED cathode (-, shorter leg) to one end of 220Ω resistor
   • Connect other end of resistor to breadboard negative rail (GND)

3. Double Check:

   • Ensure all connections are secure
   • Verify resistor values (220-330Ω)
   • Check LED polarity (longer leg = positive)

1. Open planets_esp32.ino in Arduino IDE
2. Modify WiFi credentials at the top of the file:

   const char* ssid = "YOUR_WIFI_SSID";        // Replace with your WiFi name
   const char* password = "YOUR_WIFI_PASSWORD"; // Replace with your WiFi password

1. Connect ESP32 to your computer via USB
2. Select Board:
   • Go to Tools → Board → ESP32 Arduino → "ESP32 Dev Module"
3. Select Port:
   • Go to Tools → Port → Select your ESP32 port (usually shows as "CP210x" or "Silicon Labs")
4. Set Upload Speed:
   • Tools → Upload Speed → 921600 (or 115200 if upload fails)
5. Upload Code:
   • Click Upload button or press Ctrl+U
   • Wait for "Hard resetting via RTS pin..." message

1. Prepare Data Folder:

   • Make sure the data/ folder contains:
     • index.html
     • script.js
     • style.css
     • images/ folder with all planet images

2. Upload to SPIFFS:

   • With ESP32 still connected
   • Go to Tools → ESP32 Sketch Data Upload
   • Wait for upload to complete (may take several minutes)
   • You should see "SPIFFS Image Uploaded" when done

1. Open Serial Monitor:

   • Tools → Serial Monitor
   • Set baud rate to 115200
   • Reset ESP32 (press EN button)

2. Expected Output:

   Connecting to WiFi...
   ....
   WiFi connected!
   IP address: 192.168.1.XXX
   Testing LEDs...
   Testing Mercury LED on pin 2
   Testing Venus LED on pin 4
   ... (all LEDs should light up sequentially)
   LED test complete!
   Web server started
   

3. LED Test: All 8 LEDs should light up in sequence at startup

1. Find ESP32 IP Address: Note the IP from Serial Monitor
2. Open Web Browser: Go to http://192.168.1.XXX (replace with your ESP32's IP)
3. Test Functionality:
   • Navigate through slides using arrow buttons
   • LEDs should light up for planet slides (slides 2-9)
   • No LEDs for intro, conclusion, or "how I made this" slides

• Problem: ESP32 not connecting to WiFi
• Solutions:
  • Check WiFi credentials are correct
  • Ensure WiFi network is 2.4GHz (ESP32 doesn't support 5GHz)
  • Try moving closer to router
  • Check for special characters in WiFi password

• Problem: Code upload fails
• Solutions:
  • Hold BOOT button while clicking upload
  • Try different upload speed (115200)
  • Check USB cable (use data cable, not charge-only)
  • Install CP210x or CH340 drivers

• Problem: LEDs don't light up
• Solutions:
  • Check LED polarity (longer leg = positive)
  • Verify resistor connections
  • Test with multimeter
  • Check GPIO pin numbers in code

• Problem: Web files not uploading
• Solutions:
  • Ensure ESP32 Sketch Data Upload plugin is installed correctly
  • Close Serial Monitor before uploading
  • Try uploading sketch first, then SPIFFS data
  • Check data folder structure

• Problem: Website loads but LEDs don't respond
• Solutions:
  • Check browser console for errors (F12)
  • Verify ESP32 IP address
  • Try different browser
  • Check if JavaScript is enabled

Your ESP32 also exposes these helpful endpoints:

• GET /status - Returns current LED status and ESP32 info
• GET /led/planet?slide=X - Control LEDs by slide number (X = 1-11)
• GET /led/on?planet=X - Turn on specific planet LED (X = 0-7)
• GET /led/off - Turn off all LEDs

planets/
├── planets_esp32.ino          # Main Arduino sketch
├── data/                      # SPIFFS upload folder
│   ├── index.html            # Web presentation
│   ├── script.js             # JavaScript with ESP32 communication
│   ├── style.css             # Styling
│   └── images/               # Planet images
│       ├── mercury.png
│       ├── venus.png
│       ├── earth.png
│       ├── mars.png
│       ├── jupiter.png
│       ├── saturn.png
│       ├── uranus.png
│       ├── neptune.png
│       └── solar_system_overview.png
├── README.md                 # This file
└── original files/           # Original presentation files
    ├── index.html
    ├── script.js
    └── style.css

• Memory Usage: SPIFFS partition uses ~2MB of flash memory
• Response Time: LED control response is typically <100ms
• Concurrent Users: ESP32 can handle 5-10 concurrent web users
• Image Optimization: PNG images are served directly (consider WebP for better compression)

Edit the ledPins[] array in the Arduino sketch:

const int ledPins[8] = {2, 4, 5, 18, 19, 21, 22, 23};

1. Increase array size
2. Add more GPIO pins
3. Update planet count
4. Modify web interface accordingly

Add PWM control for dimmable LEDs:

analogWrite(ledPins[planetIndex], brightness); // 0-255

• Power: ESP32 GPIO pins output 3.3V max, safe for direct LED connection with resistors
• Current: Each GPIO can handle up to 40mA, well within LED requirements
• Heat: LEDs and resistors may get warm during extended use
• Polarity: Always check LED polarity to avoid damage

If you encounter issues:

1. Check this troubleshooting section
2. Verify all connections
3. Check Serial Monitor for error messages
4. Ensure all software dependencies are installed

Happy presenting! 🌌🪐