Use this interactive web application to design custom characters and various text layouts for HD44780 display of any size
Published on January 1, 2023 · Reading time: 1 minute
What is this?
I use HD44780 character displays in my projects, both I2C and parallel. Unfortunately, I couldn't find any online tool that would allow me to create custom characters AND test them in a sequence at the same time. I could use a spare Raspberry Pi or Arduino, but it would require me to have some free space on my desk, connect all the wires, including pull-up resistors, and upload a new program every single time.
This web application implements the Hitachi HD44780 character map (ROM
Code A00: ASCII, Japanese, European characters, math symbols). It is
possible to change the memory data for the first 8 characters and get
their binary representation, compatible with
createChar() function. The text you enter must be a valid
JavaScript multiline string, so it can be copied over to your own
script with little to no changes, regardless of the programming
language you use. It is also possible to change the display size and
move the cursor around. Click the Load Sample button to get
started.
This utility is designed for developers who already know how to use the HD44780 display with their programming language of choice. Unfortunately, it is not possible for me to provide examples for every language, microcontroller or library. Check out the Arduino, MicroPython or CircuitPython docs instead.