INT 10 - VIDEO -  SELECT ACTIVE DISPLAY PAGE
AH = 05h
AL = new page number (00h to number of pages - 1) (see AH=00h)
Note:   to determine whether the requested page actually exists, use AH=0Fh
to query the current page after making this call
SeeAlso: AH=43h,AH=45h

See also: 100F

1005 - VIDEO - SELECT ACTIVE DISPLAY PAGE