Arduino with LCD1602

[albdiag]

Hello

I need some help to make work the LCD1602 with arduino

I connect the wiring as in arduino.cc to show hello word but in screen i have a\only blocks

I make all other connections ok and checked them

Any help?

Thx
Gusti

[techsupport]

Hi friend;
Do you adjust the 10k ohm potentimeter to adjust the contrast of LCD?

regards