// TinyC implementation for a standard HD44780 2x16 text LCD module

#define ep   8      // i/o pin for Enable control
#define rw   9      // i/o pin for Read/Write control
#define rs   10     // i/o pin for Register Select control


lcd_bz()
{
   int   result;

   pinlow(rs);
   pinhigh(rw);
   pinhigh(ep);
   result = pinstate(7);
   pinlow(ep);
   pinhigh(rs);
   pinhigh(rw);
   return(result);	
}

lcd_wcmd(cmd)
{
   while(lcd_bz()); // wait
   pinlow(rs);
   pinlow(rw);
   pinlow(ep);
   writeb(0, cmd, 0);
   pinhigh(ep);
   pinlow(ep);		
   pinhigh(rs);
   pinhigh(rw);
}

lcd_pos(pos)
{
   lcd_wcmd(pos | 0x80);
}

lcd_wdat(dat)	
{
   while(lcd_bz()); // wait
   pinhigh(rs);
   pinlow(rw);
   pinlow(ep);
   writeb(0, dat, 0);
   pinhigh(ep);
   pinlow(ep);	
   pinhigh(rs);
   pinhigh(rw);
}

lcd_init()
{
   lcd_wcmd(0x38); // set function, 8bits mode, 2 display lines, 5x7 dot matrix
   lcd_wcmd(0x0C); // display on, cursor off
   lcd_wcmd(0x06); // auto increment, right-shift
   lcd_wcmd(0x01); // clear display 
}

main()
{
   int   i;

   lcd_init();

   loop 
   for(i=0; i < 11; i++) {
      lcd_wcmd(0x01);       // clear display 
      lcd_pos(i);           // go to position 'i' on 1st line
      lcd_wdat('H');
      lcd_wdat('e');
      lcd_wdat('l');
      lcd_wdat('l');
      lcd_wdat('o');

      lcd_pos(0x40+i);      // go to position 'i' on 2nd line
      lcd_wdat('M');
      lcd_wdat('a');
      lcd_wdat('n');

      delay(200);
   }
}