t4(5).asm

控制子程序的循环实例。给cx

.model  small
.386
.stack  100h
.data

say1 DB 'please input a string number:',0DH,0Ah,'$'
say2 DB 'input a sting:',0DH,0Ah,'$'
say3 DB 'output a sting:',0DH,0Ah,'$'
help1 DB 0DH,0Ah,'$'
input DB ?
.code
Main   proc
Mov  ax,@data
Mov  ds,ax

MOV DX,OFFSET say1   
MOV AH,09H
INT 21H 

MOV AH,1
INT 21H
MOV BL,AL
MOV DX,OFFSET help1   
MOV AH,09H
INT 21H                       
MOV DX,OFFSET say2   
MOV AH,09H
INT 21H 

AND CH,00H
MOV CL,BL
;MOV SI,OFFSET input
CALL string1
MOV DX,OFFSET say3   
MOV AH,09H
INT 21H
CALL output1
Mov  ax,4c00h
Int   21h
Main  endp
string1 proc
	PUSH SI
	PUSH AX
	
ag:	MOV AH,1
	INT 21H
	MOV input[SI],AL
	INC SI      
	LOOP ag
	MOV input[SI+1],'$'
	
	POP AX
	POP SI   
	ret
string1 endp
output1 proc
	MOV DX,OFFSET input   
    MOV AH,09H
    INT 21H  
	ret

output1 endp
End   Main
;code ENDS