LCD1602 on Arduino

[alfio.cavallaro]

Hello friend,

I need some help to make work the LCD1602 with arduino. I followed the tutorial on http://www.geeetech.com/wiki/index.php/1602_LCD
I make all other connections ok and checked them..

It's turns on only the first line, and the second line turns on only the first part.. The display don't show "Hello World".
I adjust the I adjusted the contrast whit a 10K potentiometer..

[techsupport]

This is our test method, you can refer to the following actions.
and I have test use two kinds of Arduino board, the results display normal
Open Arduino1.0.1 or other
select File->Examples->LiquidCrystal_I2C->Hellowoard
select Tools->Board->Arduino Duemilanove w/ ATmega328
select Tools->Serial Port->COMx
Done uploading, then connect UNO and 1602.
GND<->GND 5V<->VCC A4<->SDA A5<->SCL
Confirm the connection is good, for a period of time can display properly.

[alfio.cavallaro]

I have the following error:

In file included from HelloWorld.pde:2:
C:\Arduino\libraries\LiquidCrystal_I2C/LiquidCrystal_I2C.h:80: error: conflicting return type specified for 'virtual void LiquidCrystal_I2C::write(uint8_t)'
C:\Arduino\hardware\arduino\cores\arduino/Print.h:48: error: overriding 'virtual size_t Print::write(uint8_t)'

[alfio.cavallaro]

I don't have a sda and scl pin because i don't use a serial connection but i connected Arduino with LCD as it show in a tutorial: http://www.geeetech.com/wiki/index.php/1602_LCD

[techsupport]

I retest under your phenomenon, back to you later.