!-u 1636
 05E9:1636 B80010            mov     ax, 1000
 05E9:1639 CD2F              int     2F
 05E9:163B C3                retn
 
 !-u 3985 l 28
 05E9:3985 53                push    bx
 05E9:3986 51                push    cx
 05E9:3987 85C0              test    ax, ax
 05E9:3989 7413              jz      399E
 05E9:398B 803E8C1100        cmp     byte [118C], 00
 05E9:3990 750C              jnz     399E
 05E9:3992 E8A1DC            call    1636
 05E9:3995 3CFF              cmp     al, FF
 05E9:3997 7505              jnz     399E
 05E9:3999 C6068C1101        mov     byte [118C], 01
 05E9:399E 0FBE068C11        movsx   ax, byte [118C]
 05E9:39A3 59                pop     cx
 05E9:39A4 5B                pop     bx
 05E9:39A5 C3                retn