LCD addresses
>In a 16 X 2 LCD the display addresses starts like this.
>00--------0F = 1st line - 16 locations
>40--------4F = 2nd line - 16 locations
>One article it says there are 80 display locations, 40 on each line.
yup, 40 location on each line, since internal buffer is 40 char long, all these 40 locations per line are used when u use an LCD with 40x2 or 20x4 char.
20x4 LCD is like a folded 40x2 LCD. So, the location of the third line starts where the location of first line ends, same is with the 2nd and 4th line.
This address format is adopted as they don't have to manufacture a different controller for 16x2,20x2,40x2 or 20x4. same controller+buffer works for all. and it makes life of programmer easy as he doesn't have to remember different addresses with different size of LCDs