yi.asm

这是我上汇编实验课做的三个实验程序

data segment
	mess1 db "Input the xiaoxiezimu:",13,10,"$"
data ends

code segment
    assume cs:code,ds:data
start:
  mov ax,data
  mov ds,ax
  
  mov ah,09h
  lea dx,mess1
  int 21h
x:
  mov ah,01h
  int 21h
  cmp al,'a'
  jb z
  cmp al,'z'
  ja z
  
  mov dl,al
  sub dl,20h
  mov ah,02h
  int 21h
  
  mov dl,00H   
  mov ah,02h   
  int 21h  
  jmp x

z:
  mov ax,4c00h   
  int 21h   
code ends
   end start