> >> I am having trouble initializing my 2x8 optrex
> >> lcd w/hd44780a
> >> Is it necessary to pull the unused inputs to the
> >> lcd low externally ?
>
> >Yes.
>
> NO!!
> The HD44780 is pulled-up internally, therefore, you
> can just leave unused inputs open.

Generally true, but if you don't use R/W, you must strap it low.