I've got a 16x2 character 1602A LCD module (Hitachi HD44780 compatible). I know how to use it and I've got it working with my Arduino Nano. However I haven't been able to get it working with my Due. I do realize the Due is 3.3V and the LCD module is 5V so the first thing I tried was to use one of these: https://www.adafruit.com/products/395
It didn't work. Tried with and without pull-up resistors (82k each), no difference. I also tried direct connections from the Due to the module: Didn't work either. At the best I have managed to get the module to display random characters at each CPU reset. Sometimes I get parts of the actual strings I'm trying to print but not always. I've checked the connections to the best of my abilities and tried changing to different I/O ports. My strong gut feeling is that there is something wrong with the library. Maybe it's trying to run too fast for the module on a Due???
I also did verify with a multimeter that the level shifter is working so I'm a bit clueless what to do next. Any ideas?