1-2.asm

masm,debug,link还有上课时的源程序

data segment para

data ends

stack segment para stack 'stack'
        db 64 dup(?)
stack ends

code segment  public
        assume cs:code, ds:data,ss:stack,es:data
start:
        ;Begin
        mov ax,data
        mov ds,ax
        ;Add your code here

        mov cx,1234h
        and cx,1111000000000000b
        mov cl,8
        shr cx,cl
        and ax,0000000011110000b
        not ax
        add ax,cx

        ;exit to DOS
        mov ah,4ch
        int 21h

code ends
        end start