Reflash?

[hejmowski]

Is it possible to change all characters in HD44780 LCD display? Something like 'reflashing'?

[fishthecat]

Is it possible to change all characters in HD44780 LCD display? Something like 'reflashing'?

If that was possible, I could replace all the Japanese characters that I don't use with more useful custom characters. Interesting idea.

[mattcro]

Unfortunately, the character patterns in the HD44780 (and I guess all the derivatives) are stored in mask ROM on the chip itself (ie hard-coded during manufacture of the chip), so there's no chance of modifying or reprogramming the character patterns. It would be great if it were possible. There appear to be two standard character sets: English/Japanese, and English/European, each with a few extra symbols

If you are prepared to order thousands of displays direct from the manufacturer (eg Hitachi), you can order a custom-programmed character set... companies like Matrix Orbital and CrystalFontz might have LCDs with slightly different (ie part customised) character sets.

There may well be other display controllers (not HD44780-compatible) that have an external ROM or other programmable system.

Perhaps the only other feasible system (for hobbyists like us) is to use a graphic LCD and build a super-backpack that generates all the characters and symbols you want...

Matt.

[fishthecat]

Thanks for the news. Doesn't look like it's possible then. Oh well. At least we asked.