Display HD44780 and Atmega16?

Question

Microcontrollers

I wrote a code to display text on the HD44780 display via mega16 and everything worked and displayed lines until I turned off the power (namely, I pulled the USB out of the laptop). The next time I turn it on, only one line lights up on the display, although I initialize two and nothing more. The display does not react in any way and does not output anything. I set all the ones on the control and data lines, I measured the voltage with a multimeter, there are 4.05V, i.e. signal reaches the display. How can it be started, or has it burned out and how to understand this?

Answer 1

Filling the display in half is a standard test. Somewhere at you with initialization of a problem.

Answer 2

Here is the initialization
[Spoiler=]

void LCD_init()
{	
  _delay_ms(40);//
  DDR_DATA |= 0xF0;//ïîðòû íà 
  PORT_DATA |= 0xF0;//âûõîä
  DDR_SIG |= (ON<<E)|(ON<<RW)|(ON<<RS);//óïðàâëÿþùèå ïîðòû 
  PORT_SIG |= (ON<<E)|(ON<<RS);//íà âûõîä
  PORT_SIG &= ~(ON<<RW);//ïîðò ÷òåíèÿ/çàïèñè íà íà çàïèñü
  _delay_ms(40);
  LCD_write(BUS_LINE,RS_COM);//2 ëèíèè äàííûõ, 4 áèòà øèíà
  LCD_write(0x01,RS_COM);//î÷èñòêà ýêðàíà
  LCD_write(0x06,RS_COM);//èíêðåìåíò àäðåñà ýêðàí íå äâèæåòñÿ
  
  LCD_write(0x0C,RS_COM);//âêëþ÷èòü äèñïëåé

}

[/spoiler]