Was ist das genau für ein Display ?

Was ich schon öfter gelesen habe:

the KS0066 is a Samsung controller which claims to be 44780 compatible
But as with all Samsung controllers they are not really so.
I don't have any displays with them so I can not do any tests. Maybe it is
the same problem as with most other Samsung types: the busy output is
very delayed so the driver gets false readings.