Unicode? MAX7219


I'm trying to implement Asian symbols with my max7219 and using the 8x8 led displays.
I've had a look online and I've found libraries for the max7219 but it is only in ASCII. I was wondering if there was an easy way of implementing using a UNICODE library - assuming there is one.

I'd like to easily copy and paste say " な " this character into my code and print it onto the LED displays. So far, all attempts have not been working. My other option is to use binary/hex to manually draw up the symbols but I would really prefer to make it easy for the user to copy and paste any character and it prints onto the LEDs. Or will I have to create my own Arduino Library?

Any help is greatly appreciated!

Many thanks.


Or will I have to create my own Arduino Library?

Yes. The existing libraries have fonts defined for standard letters, numbers, and some punctuation. If you want to define other symbols, you'll need to extend the font definition table, and possibly rewrite the whole library to deal with unicode characters.

I would tend to solve this by writing a java program that would print the characters you want onto an 8*8 image object, and then read the image back and convert it into suitable initializers for the compiler. The trick is finding a font that works on your platform.

Another alternative would be finding a library that understands font files a bit more directly.

Incidentally - if your LED display had more brightness levels than on/off, then it might be possible to gain readability by antialiasing the characters. The visual effect is that they wind up looking like much higher resolution characters viewed through some frosty glass.

If you like, drop me a PM and I'll have a bash at writing you some Java to do the job. I'm thinking an input box that accepts any unicode string you want to copy/paste or type into it, a dropdown to select your font, and an output box with a char grids[8] = {}; initializer in it.

Maybe it's time for me to learn JavaFX :slight_smile: .

Have a look at the Parola and the MD_MAX72xx libraries. You can define your own font and I have a font editor that works as a macro in MS Excel.

There are already files for Japanese font. I don't use unicode, so the 'typing' to 'display' mapping will need to be done by your code if you use this library.

Links in my signature block.