assume cs:code
stack segment
db 128 dup(0)
stack ends
code segment
start: mov ax,stack ; init stack
mov ss,ax
mov sp,128
push cs ; mov NI9 to 0:204
pop ds
mov si,offset ni9
mov ax,0
mov es,ax
mov di,204H
mov cx,offset ni9e - offset ni9
cld
rep movsb
; save BIOS origin int9
push es:[9*4] ; IP
pop es:[200H]
push es:[9*4+2] ; CS
pop es:[202H]
; set ni9 as int9
cli
mov word ptr es:[9*4],204H
mov word ptr es:[9*4+2],0
sti
mov ax,4c00H
int 21H
ni9: push ax
push es
push bx
push cx
mov bx,0
mov es,bx
pushf ; call BIOS origin int9
call dword ptr es:[200H]
in al,60H ; get keyboard input from port 60H
cmp al,3bH ; cmp with F1
jne ni9r
; change screen color
mov ax,0b800H
mov es,ax
mov bx,1
mov cx,2000 ; 2000 chars per page
lp: inc byte ptr es:[bx]
add bx,2
loop lp
ni9r: pop cx
pop bx
pop es
pop ax
iret
ni9e: nop
code ends
end start
以上是程序代码运行环境WIN64 DOSBOX
按F1不变色啊
------解决方案--------------------
没有 Win64，在 xp/sp3 的 DOSBox 里试运行了下，是可以的。