Note
This is a web-version of a tutorial chapter embedded right into the XOD IDE.
To get a better learning experience we recommend to install the
desktop IDE or start the
browser-based IDE, and you’ll see the same tutorial there.
Display Text on LCD
There are many variants of liquid crystal displays (LCD). Among them, text displays are simplest to communicate with. A text LCD can expose either of physical interfaces:
- I2C
- Parallel
XOD supports both.
Circuit (parallel interface) #
↓ Download as a Fritzing project
Circuit (I2C interface) #
↓ Download as a Fritzing project
Exercise #
Let’s show some text on an LCD.
- Examine your LCD and decide which node fits it. Remove another one.
- Assemble the circuit that matches your LCD model.
- Bind pins or set the I2C address.
- Bind “Wuzzup!” to the
L1pin. - Link
tweak-stringwithL2. - Upload the patch with the interactive session enabled.
- Select
tweak-string. - Type some text and press the Enter key.
👆 Too many variations #
The world of text LCDs is too wide to guess your LCD pinout and parameters. The provided circuit will work for some models, but not for others. Refer to your particular display documentation to precisely determine its address, data pinout, contrast pin wiring, digital and backlight powering scheme.
For the rest of the tutorial we assume you have an I²C LCD listening on 27h address. Adjust patches accordingly if you’ve got another model.