Optional - LCD Display¶
A 16x2 I2C LCD shows spool info directly on the scanner.
What You Need¶
- 16x2 character LCD with I2C backpack (address 0x27)
- 2 jumper wires (SDA, SCL) + VCC + GND
Wiring¶
| LCD Pin | ESP32-WROOM | ESP32-S3-Zero |
|---|---|---|
| SDA | GPIO 23 | GPIO 1 |
| SCL | GPIO 22 | GPIO 2 |
| VCC | 5V or 3.3V | 5V or 3.3V |
| GND | GND | GND |
Note
Most I2C LCD backpacks work with both 3.3V and 5V. If the display is dim on 3.3V, try 5V for the backlight.
What It Shows¶
- Boot: "SpoolSense" + firmware version
- WiFi: Connection status and IP address
- Spool scanned: Material type, remaining weight
- Keypad entry: Tool number being typed
- Write operations: Progress and result
Enable in Firmware¶
The LCD is enabled via the installer or web config page (/config > Hardware > LCD Display toggle). No recompile needed.