8259.asm

汇编程序

		assume cs:code
        	code segment public
        	org 100h
start:		mov	cx,0
start1: 		cli
			mov 	dx,04a0h
        		mov 	ax,13h
        		out 		dx,ax			;ICW1, ICW4 NEEDED,单片00010011
        		mov		dx,04a2h
			mov 	ax,80h
			out 		dx,ax 	 	 	;ICW2 中断类型80h，1000000
			mov 	ax,01
			out 		dx,ax   		;ICW4
			mov 	ax,00h
			out 		dx,ax    		;OCW1, 开放所有中断
			mov 	ax,0
			mov 	ds,ax
			mov 	si,200h  		;初始化中断向量表
			mov 	ax,offset hint
			mov 	ds:[si],ax
			add 		si,2
			mov 	ds:[si],100h
			mov 	ax,0
			;jmp		start
			sti
waiting:
	 		cmp 		ax,55h
                        nop
                        nop
                        nop
                        nop
                        nop
                        nop
                        nop
                        nop
	 		jne 		waiting		；没发生中断，则等待
	 		nop
	 		nop
	 		mov 	dx,04b0h
	 		xor		cx,0ffh
	 		mov 	ax,cx
	 		out		dx,ax			;LED灯亮灭一次
	 		jmp 		start1
                        nop
hint: 		cli
        		nop
                        nop
                        nop
                        nop
                        nop
                        nop
                        nop
                        nop
			mov 	ax,55h
			nop
			iret
code ends
end start