I wrote myself an HD44780 LCD driver years ago, and I still use it to this day. I quickly added that to the micro to try a simple 'Hello, world!". Unfortunately no dice. I checked all the connections, and they seem fine. This leaves the elephant; I'm using a 3.3v micro and a 5v LCD! I tried another LCD which I am sure I've used with the 5V micro before, and I get the same result. I think my memory of using an LCD with a 3.3v micro might be flawed.