How to use an SSD1603 (oled 0.96'') with Attiny85

Hi there!!! iam from Argentina. Sorry for my english. Iam having a problem....after days searching and triyng i give up and post it.

My proyect: Oled i2c + termistor + ATTINY85 (programed with a Nano as ISP).

I upload the sketch (no error while loading), but the screen remains black.....

I tried with another Nano, with another ATTINY85 and i tried the displays directly with the nano. Every component works fine, but i cannot get to work the oled with the attiny85.

#include <Arduino.h>
#include <U8x8lib.h>

U8X8_SSD1306_128X64_NONAME_SW_I2C u8x8(2,0);
void setup(void) {
u8x8.begin();
}

void loop(void) {
u8x8.setFont(u8x8_font_chroma48medium8_r);
u8x8.drawString(0,0,"Hello World!");
delay(1000);
}