中断及其处理

中断及其处理

中断的概念

编制中断处理程序

assume cs:code
code segment
start:
;do0安装程序
	mov ax,cs
	mov ds,ax
	mov si,offset do0 
	mov ax,0
	mov es,ax
	mov di,200h
	mov cx,offset do0end-offset do0
	cld
	rep movsb

;设置中断向量表
	mov ax,0
	mov es,ax
	mov word ptr es:[0*4],200h
	mov word ptr es:[0*4+2],0

;显示字符串"overflow!"
do0:
	jmp short do0start
	db "overflow!"
do0start:
	mov ax,cs
	mov ds,ax
	mov si,202h
	mov ax,0b800h
	mov es,ax
	mov di,12*160+36*2
	mov cx,9
  s:mov al,[si]
    mov es:[di],al
	inc si
	add di,2
	loop s
	
	mov ax,4c00h
	int 21h
do0end:nop
code ends
end start

单步中断

由int n引起的中断