data segment
X dw 0000000000001100d
data ends

code segment
assume cs:code, ds:data
main proc far
start:
push ds
mov ax, 0
push ax
mov ax, data
mov ds, ax
mov ax, X
mov bx, 0000000000000111d　　;用来屏蔽X的非第三位的所有数
mov cl, -3　　　　　　　　　 ;移位控制器　
mov dx, 6　　　　　　　　　　;计数器
loop1:
add cl, 3
shr ax, cl
and ax, bx
add al, 30h
mov dl, al
mov ah, 2
int 21h
dec dx
jnz loop1
ret
main endp
code ends
end start

多谢楼上的，按你说的我已经改过了，可是还是过不了．．．．．
＊＊＊＊＊＊＊＊＊＊＊改进版如下＊＊＊＊＊＊＊＊＊＊＊＊

data segment
X dw 0000000000001100b
data ends

code segment
assume cs:code, ds:data
main proc far
start:
push ds
mov ax, 0
push ax
mov ax, data
mov ds, ax
mov bx, 0000000000000111b　　;用来屏蔽X的非低三位的所有数
mov cl, -3　　　　　　　　　 ;移位控制器　
mov ch, 0
mov dh, 6　　　　　　　　　　;计数器
loop1:
mov ax, X
add cl, 3
shr ax, cl
and ax, bx
add al, 30h
push al
inc ch
dec dh
jnz loop1
loop2:
pop al
mov dl, al
mov ah, 2
int 21h
dec ch
jnz loop2
ret
main endp
code ends
end start

我用的是最简单的那个MASM
是我搞错了，栈只能以字操作
已经改过了　可是编译时还报错
＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊
Microsoft (R) Macro Assembler Version 5.00
Copyright (C) Microsoft Corp 1981-1985, 1987. All rights reserved.

Object filename [4-4pro2.OBJ]:
Source listing [NUL.LST]:
Cross-reference [NUL.CRF]:
4-4pro2.asm(14): error A2027: Operand expected
4-4pro2.asm(15): error A2027: Operand expected
4-4pro2.asm(17): error A2027: Operand expected

50042 + 451366 Bytes symbol space free

0 Warning Errors
3 Severe Errors

E:\huibian>
＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊

报的错不可理解