The 16×2 character LCD using the HD44780 controller is the most common text display for Arduino projects. It shows 16 characters on 2 rows and can be controlled in 4-bit or 8-bit mode, or via I2C backpack module.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1 | VSS | Ground | GND |
| 2 | VDD | 5V power supply | PWR |
| 3 | VO | Contrast adjust, connect to pot | ADC |
| 4 | RS | Register select, HIGH=data LOW=cmd | I/O |
| 5 | RW | Read/write, tie LOW for write | I/O |
| 6 | E | Enable clock | I/O |
| 7 | D0 | Data bit 0 (not used in 4-bit mode) | I/O |
| 8 | D1 | Data bit 1 (not used in 4-bit mode) | I/O |
| 9 | D2 | Data bit 2 (not used in 4-bit mode) | I/O |
| 10 | D3 | Data bit 3 (not used in 4-bit mode) | I/O |
| 11 | D4 | Data bit 4 | I/O |
| 12 | D5 | Data bit 5 | I/O |
| 13 | D6 | Data bit 6 | I/O |
| 14 | D7 | Data bit 7 | I/O |
| 15 | A | Backlight anode, 5V via 100R | PWR |
| 16 | K | Backlight cathode, GND | GND |