;从键盘输入一个字符显示它的编码,(一共能输入30个字符)
;按Esc键退出.
data segment
org 1000h
h1 db '的编码是$'
h2 db '按Esc键退出$'
data ends
stack segment para stack 'stack'
db 100 dup(?)
stack ends
code segment
assume cs:code,ds:data,ss:stack
start: mov ax,data
       mov ds,ax
       mov ax,stack
       mov ss,ax
;***************************************************
       mov cx,50   
p1:    mov ah,1
       int 21h        
       push ax
       cmp al,1bh
       jz q1
       mov dx,offset h1
       mov ah,9
       int 21h
       pop ax
       mov ah,al
       push cx  
       mov cl,4
       shr al,cl
       pop cx
       call z1
       mov al,ah
       and al,0fh
       call z1
       lea dx,h2
       mov ah,9
       int 21h
       call z2     ;回车换行         
       loop p1
;****************************************************
q1:    mov ah,4ch
       int 21h
z1     proc       
       push ax
       push bx
       push cx
       push dx
       cmp al,9
       ja x1
       add al,30h
       jmp x2
x1:    add al,37h
x2:    mov dl,al
       mov ah,2
       int 21h
       pop dx
       pop cx
       pop bx
       pop ax
       ret
z1     endp
z2     proc 
       push ax
       push bx
       push cx
       push dx
       mov dl,0dh
       mov ah,2
       int 21h
       mov dl,0ah
       mov ah,2
       int 21h
       pop dx
       pop cx
       pop bx
       pop ax
       ret
z2     endp
code   ends
       end start