void init_port(void);
void outdata(char);
void outcontrol(char);
void delay1(int);
void lcd_control_write(void);
void init_lcd(char line1,char line2);
void write_data(char);

void setup(){
  init_port();
  init_lcd();
}

void loop(){
  write_string_revolve();
}
//LCD initialization
void init_lcd()
{
  outdata(0x38);   // 8bit 2 line
  lcd_control_write();
  outdata(0x0c);   // Display on Cursor off
  lcd_control_write();
  outdata(0x01);   // Clear Display
  lcd_control_write();
  outdata(0x06);//auto increment
  lcd_control_write();
  
}
//LCD revolving part
void write_string_revolve()
{ 
  char line1_start,line2_end; // define ending and starting address
  line1_start=0x80;
  line2_end=0xcf;
  //Loop through to display and revolve
  for(volatile char i=0;i<28;i++)
  { 
    outdata(line2_end);// set cursor to line2 
    lcd_control_write();
    write_string("ECEN Academy");//display ECEN Academy at line 2 address
    LCD_clear(); //Clear display
    outdata(line1_start);//set cursor to line 1 
    lcd_control_write();
    write_string("Welcome to");//display "Welcome to" at line address
    LCD_clear();//Clear display
    delay1();//small delay to make the changes visible
    line1_start++;line2_end--;//increment and decrement line1 and line 2 address
    LCD_clear();//Clear display
  }
}
  
void write_string(char *ptr)
{ 
  while(*ptr != 0)
  {
    write_data(*ptr);
    ptr++;
  }
}

// Initialize Port
void init_port()
{
  volatile char *portf_dir  = (volatile char *)0x30;
  volatile char *portk_dir  = (volatile char *)0x107;
  *portf_dir = 0xFF;
  *portk_dir = 0x03;
}
//output data to portf (pin D0 -D7)
void outdata(char out_data)
{
  volatile char *portf_data = (volatile char *)0x31; 
  *portf_data = out_data;
}
//Enable and Register select
void outcontrol( char out_data)
{
  volatile char *portk_data = (volatile char *)0x108; 
  *portk_data = out_data;
}
void lcd_control_write( void )
{
  outcontrol(0x01);
  delay(1);
  outcontrol(0x00);
  delay(1);
}

// display a character on LCD
void write_data(char wr_data)
{
  outdata(wr_data);
  outcontrol(0x02);
  delay(1);
  outcontrol(0x03);
  delay(1);
  outcontrol(0x02);
  delay(1);
}

void delay1()
{
  for(volatile long i =0;i<100000;i++);
}

void LCD_clear()
{
  outdata(0x01);
  lcd_control_write();
}