Int 10 Fn FF - Topview - Update Screen From Shadow Buffer [V]
AH = FFh
CX = number of consecutive changed characters
ES:DI -> first changed character in shadow buffer
Return: nothing
Notes: avoid CX=0000h
DESQview will discontinue the automatic screen updating initiated by
AH=FEh after this call
not supported (ignored) by DESQview/X 1.0x
See Also: AH=93h,AH=FEh