Critical Assembly Rules
- OLED Alignment: The 0.96" OLED is exactly 27x27mm. Cut a rectangular window slightly smaller (approx 25x14mm) in the top third of the front lid just for the glass screen to poke through.
- Coil Placement is King: Use a drop of superglue or hot glue to stick the rectangular copper coil completely flat against the inside wall of the front lid. Do NOT try to mount the coil on your perfboard at the back of the box!
- The "Clear Zone" (Red Box): The spatial area directly behind the copper coil MUST remain empty. Do not allow the ESP32's metal wifi shield or the thick USB cable to block this area, otherwise your card reading range will drop to zero. Mount the ESP32 motherboard toward the bottom edge of the back panel.
- Buzzer: Drill a small grid of 2mm holes so the sound can escape. Glue the buzzer face-down over the holes on the inside lid.
Mounting Base Guide
- Main Spinal Board: Use a 5x7 cm FR4 Perfboard. Solder female headers here so you can plug the ESP32 and RDM6300 on top.
- Standoffs: Use 5mm M3 plastic standoffs or high-strength double-sided foam tape to mount the Perfboard to the back wall of the box. Ensure the board is away from the RFID coil zone.
- Lid-to-Base Wiring: Use flexible 24AWG or 26AWG multi-strand wires for components on the lid. Solid core wires will snap after opening/closing the lid a few times.
Bill of Materials (BOM) Checklist
| Component |
Description |
| Casing | 100x68x40mm ABS Waterproof Junction Box |
| Base Plate | 5x7 cm FR4 Prototyping Perfboard |
| Headers | 2x 15-pin Female Headers (for ESP32) |
| Adhesive | Hot Glue or 3M VHB Double-Sided Tape |
| Power | 5V 2A DC Power Adapter + Female DC Jack |
Hardware Pin Wiring Guide
Connect your components to the ESP32 DevKit v1 board exactly as shown below.
1. RDM6300 RFID Reader (UART)
| RDM6300 Pin | ESP32 Pin | Notes |
|---|
TX (Pin 1) | GPIO16 (RX2) | Serial connection for reading data |
RX (Pin 2) | Not Connected | |
GND (Pin 3) | GND | Common ground |
VCC (Pin 4) | 5V / VIN | Requires 5V power, not 3.3V |
ANT (Pins 5&6) | Antenna Coil | Connect the provided rectangular coil here |
2. SSD1306 OLED Display (I2C)
| OLED Pin | ESP32 Pin | Notes |
|---|
GND | GND | Common ground |
VCC | 3.3V | Standard OLED power |
SCL | GPIO22 | I2C Clock |
SDA | GPIO21 | I2C Data |
3. RGB LED (Common Cathode)
| LED Leg | ESP32 Pin | Notes |
|---|
Longest Leg (-) | GND | Common ground |
| Red Leg | GPIO25 | Connect via a 220Ω resistor |
| Green Leg | GPIO26 | Connect via a 220Ω resistor |
| Blue Leg | GPIO27 | Connect via a 220Ω resistor |
4. Active Buzzer
| Buzzer Pin | ESP32 Pin | Notes |
|---|
Positive (+) | GPIO32 | Signal pin (Active HIGH) |
Negative (-) | GND | Common ground |