INT 10,FF - Update DESQView/TopView Virtual Screen Regen Buffer

AH = FF

CX = number of characters changed

ES:DI = pointer to first character in buffer to change, ES is

set to segment returned by ~INT 10,FE~

returns nothing

- the physical screen does not get updated until INT 10,FF is

called in TopView

- it is not necessary to make this call under DESQView since it

handles updates automatically

- calling this function under DESQView will cancel the automatic

update mode