INT 50 - PC Thuis Organizer Shell - PLOT TEXT
        AX = 0002h
        ES:BX -> text string
        DH,DL = row,column of upper left corner
        DI = window handle
Return: AX = status
            0000h successful (text fits in window)
            FFFFh error
Program: The PC Thuis Organizer Shell was written by John Vanderaart and
          published in the June/July 1990 issue of PC Thuis Power magazine