The Nano converts incoming serial characters to 4-bit codes needed by the LCD. Three non-printable characters are used for special functions (clear screen, backlight on, backlight off)

- Hitachi comptable 20x4 display
- Arduino Nano
- FTDI USB-serial
- 2n2222 based backlight control

- USB-to-serial (FTDI driver)
- 20x4 character display
- Ascii character set: 32d to 127d
- Backlight control

- USB powered
- mini-USB connector
- ~80mA @5vdc max

Special characters:
0x11 17d == clear LCD display
0x12 18d == set LCD backlight OFF
0x13 19d == set LCD backlight ON