another "LCD wont display text" problem! Help much appreciated.

Hi all.

I've been through the Ladyada tutorial, and cant get my Parallel 2*16 LCD working with the Mega 2560.

I know its been asked a thousand times before, but I HAVE read all the threads, and still have no solution. The LCD lights up with the top row full of blocks, the bottom row is totally blank, and no text....

I've soldered flying leads to the LCD, and have checked the connections over and over again. They're correct. The only thing that could be wrong is that I dont have a 10K pot, so am using a 100k pot. This shouldnt make a difference because all it does is give a voltage for the contrast on the display? I've racked it back and forth and there's defo no text there...

I've checked the grounds aren't dropping and voltage, checked that the lives are getting 5v bang on. I'm using the sketch supplied with the Arduino compiler, it builds and uploads without any errors, the header file is installed in the library properly.

I'm struggling... Any ideas? I've read that its almost always the connections, so I've checked them over and over, and they seem good. I even reassigned the pins in the sketch and used different I/O pins to see if it was a dodgy socket on the Mega.

Pfffffff, any ideas? I can post a picture if preferred - it is a little Heath Robinson, but I cant see that i've done anything wrong.

Many thanks,


You’re sure you’ve done everything the correct way, but still it doesn’t work.
You’ve told us all is correct because you checked.
Now tell us how you did connect it, what display you’ve got (a link would be helpful) and a drawing or a clear picture on how you have it connected.
Also show your sketch as it is now.

Did you connect LCD pin 5 to GND?