INT 13,F - Write Sector Buffer (XT & portable only)
AH = 0F on return: AL = number of sectors actually transferred AH = status (see INT 13,STATUS) CF = 0 if successful = 1 if error
AH = 0F on return: AL = number of sectors actually transferred AH = status (see INT 13,STATUS) CF = 0 if successful = 1 if error