This time we will add support for Char LCD with size 40×4. Such display is a special case, when we look at the internal schema we will see that its in fact two-in-one lcd. It has two lcds, one lcd goes on top and second on bottom.
It’s because one HD 44780 can display maximum 80 chars and this is 40×2. If we want 160 chars we must double this.
This way we have two 40×2 lcds. For our purpose lets call such display a twin-lcd.
