INT 10 - VIDEO - TELETYPE OUTPUT
        AH = 0Eh
        AL = character to write
        BH = page number
        BL = foreground color (graphics modes only)
Desc:   display a character on the screen, advancing the cursor and scrolling
          the screen as necessary
Notes:  characters 07h (BEL), 08h (BS), 0Ah (LF), and 0Dh (CR) are interpreted
          and do the expected things
        IBM PC ROMs dated 4/24/81 and 10/19/81 require that BH be the same as
          the current active page
SeeAlso: AH=0Ah