菜鸟问题麻烦帮下

我写了个程序是显示提示..然后输入名字...

输入第一次后我已经把..Buffer的内容全部变成空白然后在显示出来..

为什么在屏幕上的显示效果没变了..我表达能力不杂..如果有什么地方说得不清楚..

我可以在详细的说下...

		.model	small

		.stack 	64

		.data

	para_list	label	byte

	MaxLen		db	20

	ActLen		db	?

	Buffer		db	21	dup(' ')

	Prompt		db	'Name? ', '$'

		

			.code

	.386

	Main	proc	far

		mov	ax,@data

		mov	ds,ax

		mov	es,ax

		call	Clear_Screen

		

	A20:

		mov	dx,0000

		call	Set_Cursor

		call	Input

		cmp	ActLen,00

		je	A30

		call	Enter_Model

		call	Display

		call	FlushBuffer

		call	Display

		jmp	A20

	A30:	

		mov	ax,4c00H

		int	21H

	Main	endp

	

	Input	proc

		push	ax

		push	dx

		call	FlushBuffer

		mov	ah,09H

		lea	dx,Prompt

		int	21H

			

		mov	ah,0aH

		lea	dx,para_list

		int	21H

		pop	dx

		pop	ax

		ret

	Input	endp

	

	Enter_Model	proc

		movzx	bx,ActLen

		mov	Buffer[bx],07H

		mov	Buffer[bx+1],'$'

		mov	dl,ActLen

		shr	dl,1

		neg	dl

		add	dl,40

		mov	dh,12

		call	Set_Cursor

		ret

	Enter_Model	endp

	

	Display	proc

		pusha

		mov	ah,09H

		lea	dx,Buffer

		int	21H

		popa

		ret

	Display	endp

	

	Clear_Screen	proc

			pusha

			mov	ax,0600H

			mov	bh,30

			mov	cx,0000

			mov	dx,184FH

			popa

			int	10H

			ret

	Clear_Screen	endp

	

	Set_Cursor	proc

			mov	ah,02H

			mov	bh,00

			int	10H

			ret

	Set_Cursor	endp

	

	FlushBuffer	proc

			pusha

			mov	cx,10

			lea	si,Buffer

		B30:

			mov	WORD ptr [si],2020H

			add	si,2

			loop	B30

			mov	BYTE ptr [si],'$'

			popa

			ret

	FlushBuffer	endp

	end	Main