端口的读写

端口的读写

assume cs:code,ds:data,ss:stack
data segment
  dw 0123H,0456H,0789H,0abcH,0defH,0cbaH,0987H
data ends
stack segment
  dw 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
stack ends
code segment
start:mov ax,stack
	  mov ss,ax
	  mov sp,20h
	  mov ax,data
	  mov ds,ax
	  
	  mov bx,0
	  mov cx,8
	s:push [bx]
	  add bx,2
	  loop s
	  
	  mov bx,0
	  mov cx,8
   s0:pop [bx]
      add bx,2
	  loop s0
	  
	  mov ax,4c00h
	  int 21h
code ends
end start

操作CMOS RAM芯片

assume cs:code
code segment
start:mov al,8;取得月份数据
      out 70h,al
	  in al,71h
	  
	  mov ah,al ;分离月份的十、个位
	  mov cl,4
	  shr ah,cl
	  and al,00001111b
	  
	  add ah,30h;转换为ASCLL码
	  add al,30h
	  
	  mov bx,0b800h;//显示
	  mov es,bx
	  mov byte ptr es:[160*12+40*2],ah
	  mov byte ptr es:[160*12+40*2+2],al
	  
	  mov ax,4c00h
	  int 21h
code ends
end start