Leaderboard

Heya. I had an issue with contrast on a pair of 40x2 LCDs. It was the old issue of negative contrast voltage rearing its head again. I solved it using this schem: http://www.stephenhobley.com/blog/2011/03/28/creating-a-negative-voltage-from-a-positive-one/ I tried it using 3.3v from the J5 port, no dice. Likely because I'm using an NE555 timer, would probably work with the CMOS version. Anyway, it solved the issue I was having. Good luck! /t/