LCD1602 (IIC) Character Display

LCD1602 is a 16-column x 2-row character LCD. The common I2C adapter board uses PCF8574, with address typically 0x27 or 0x3F.

Current Support Status

The current FastBee LCD peripheral type (type 36) runtime driver is based on U8g2, which covers SSD1306/SH1106 graphical OLEDs; it does not yet include a built-in HD44780/PCF8574 character display driver. Therefore, LCD1602 can currently be kept as a configuration placeholder and future expansion document. After importing, it cannot be directly driven by ACTION_OLED_DISPLAY(27).

Available alternatives:

• For multi-line text and sensor variable display: use SSD1306/SH1106 OLED.
• For displaying only 4-digit numbers: use TM1637 seven-segment display.
• If LCD1602 is required: add HD44780/PCF8574 driver in esp32s3-F16R8 or custom firmware.

Currently, LCD1602 is recommended to be kept as a placeholder configuration in the peripheral page; when display actions are actually needed, refer to the OLED or TM1637 available page entries first.

Hardware Wiring

LCD1602 I2C Pin	ESP32 Pin	Description
VCC	5V or 3.3V	Power supply per module requirements
GND	GND	Common ground
SDA	GPIO21	I2C data
SCL	GPIO22	I2C clock

Configuration Placeholder Example

The example is disabled by default and is only for recording wiring and reserving future expansion. Do not enable after importing unless the firmware has been supplemented with the LCD1602 driver.

{
  "id": "lcd1602_01",
  "name": "LCD1602-IIC Character Display",
  "type": 36,
  "enabled": false,
  "pinCount": 2,
  "pins": [21, 22, 255, 255, 255, 255, 255, 255],
  "params": {
    "width": 16,
    "height": 2,
    "interface": 2
  }
}

Recommended Driver Extension

1. Add character display mode recognition in LCDManager: width=16, height=2, interface=2.
2. Add PCF8574 I2C write timing, supporting clear screen, cursor positioning, string writing, and backlight control.
3. Reuse ACTION_OLED_DISPLAY(27) in peripheral execution, splitting multi-line text into 2 lines of 16 characters each.
4. Add address parameter to documentation and UI, default 0x27, optional 0x3F.

Notes

• LCD1602 has a limited character set and typically does not support Chinese characters.
• The I2C adapter board requires contrast adjustment via a potentiometer, otherwise it may appear as if nothing is displayed.
• 5V powered modules may have 5V I2C pull-ups; verify level safety for ESP32.