Hello there and thanks in advance for answering .

I am currently trying to connect a 20*4 LCD to a Teensy 3.2, but it does not work. I have connected it like this:
Vss-> ground
VDD-> power (3.3V)
V0->middle pin of the potmeter
RS-> pin 10
RW-> ground
E->pin 9
D4->pin 5
D5->pin4
D6->pin 3
D7->pin 2

When I do this, it only lights up and that is all. I cannot change the brightness with the potmeter and I also can't programm any text on it. Does anybody know what is going wrong? Maybe the lcd only works on an aruino (that is 5V)? I hope that anybody can help me out.

Joris