This embedded LCD display is based on the Hitachi HD44780 chipset and is also sold with a little board already soldered to the screen board that allows you to manage the screen via the I2C interface. For ease we are going to connect it to the FTDI FT232H device, of which there is a dedicated page on this site - refer to the above page for installation.
This display must be connected to the FTDI FT232H development board via I2C protocol. The connection connectors are listed below:
| Image | Board FT232H | Display HD44780 |
|---|---|---|
|
AD0 | SCL |
| AD1 + AD2 | SDA | |
| +5V / +3.3V | VDD | |
| GND | GND |
The default hexadecimal address of this display is "27", but we can change it by soldering pads A0/A1/A2, obtaining different addresses, as shown in the following table:
| A2 | A1 | A0 | Hexadecimal address |
|---|---|---|---|
| C | C | C | 20 |
| C | C | O | 21 |
| O | C | O | 22 |
| C | O | O | 23 |
| O | C | C | 24 |
| O | C | O | 25 |
| O | O | C | 26 |
| O | O | O | 27 |
| C = Closed, O = Open | |||
To get the hexadecimal address of this display, go to the PyFTDI website and download the following Python script. Once downloaded, run it via the Python interpreter. The output of the above script is as follows:
admin@RT-AC86U:/# python3 i2cscan.py 0 1 2 3 4 5 6 7 8 9 A B C D E F 0: . . . . . . . . . . . . . . . . 1: . . . . . . . . . . . . . . . . 2: . . . . . . . W . . . . . . . . 3: . . . . . . . . . . . . . . . . 4: . . . . . . . . . . . . . . . . 5: . . . . . . . . . . . . . . . . 6: . . . . . . . . . . . . . . . . 7: . . . . . . . . .
To manage this display, we can use one of the following Python libraries:
