LiquidCrystal library not working with ATtiny84v-10PU

here is my code-

#include <LiquidCrystal.h>

const int rs = 0, en = 1, d4 = 2, d5 = 3, d6 = 7, d7 = 8;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);

void setup() {
  lcd.begin(16, 2);
  // Print a message to the LCD.
  lcd.setCursor(0, 1);
  lcd.print("hello, world!");

void loop() {


the lcd turned on. and this is what it printed-

at first , the lcd would show a line of blocks .
the lcd then cleared.
finally, it stopped printing anything.

the model is a jhd162a

the controller is ks0066(as far as i know:))

attiny clock- internal 1 mhz
supply- 5v (arduino uno 5v pin)
programmer- arduino uno as isp

what am i trying to do - print hello world on the screen

lcd type- 16*2
platform- breadboard with some jumper wires
contrast - maximum- connected the pin controlling contrast directly to ground
used library- LiquidCrystal.h
no fuses touched (i am a newbie , well i dont know if i can or cannot but , clarification :))
lcd prior tests results using uno- slow at printing but printed hello world 3 times and ran a sketch which printed the number of seconds every 5 seconds
checked wiring. pretty fine,

Check to be sure the grounds are connected!

Which Arduino core are you using for the attiny? Some have alternative pin mappings between Arduino pins and physical package pins.
Maximum contrast may give you only black rectangles instead of the desired characters.

Thank you. I checked the grounds but the t were connected.i uploaded a second sketch which should print millis()/1000 every 5 seconds. I actually was trying to reattach the data wires when I found that removing the second data wire prints some random character s and reattaching it prints exactly what is intended after th random characters even at the maximum contrast. I think that the start sequence is just too fast for the lcd. Is it so?

sorry for the spelling mistakes(switched to another keyboard now)

this > GitHub - damellis/attiny: ATtiny microcontroller support for the Arduino IDE< is the one (the file containing the board stuff) that i am using

sorry for the spelling mistakes(switched to another keyboard now)

Well there is this option to 'edit' posts in this forum...

By the way for clarification are you using a potentiometer for the contrast pin ( clarification )?
If you are not then please tell...

thank you so much for replies :slight_smile:
extremely sorry , i forgot about the edit option. :smiley:
i did not use a pot at the contrast pin. directly connected it to ground
thanks again!