INT 15 - TopView - "DISPEROR" - POP-UP ERROR WINDOW
        AX = 101Fh
        BX = bit fields
             bits 0-12: number of characters to display
             bits 13,14: which mouse button may be pressed to remove window
                         00 = either
                         01 = left
                         10 = right
                         11 = either
             bit 15: beep if 1
        ES:DI -> text of message
        CH = width of error window (0 = default)
        CL = height of error window (0 = default)
        DX = segment of object handle
Return: BX = status: 1 = left button, 2 = right, 27 = ESC pressed
Note:   window remains on-screen until ESC or indicated mouse button is pressed