03.asm

汇编语言的一些简单代码

data segment 
m1 db 'please put into sexadecimal number',13,10,'$' 
m2 db 'you put into wrong number',13,10,'$' 
m3 db 13,10,'$' 
data ends
CODE   SEGMENT
       ASSUME  CS:CODE,ds:data
START:
       mov ax,data
       mov ds,ax
       mov cx,4  
input: mov ah,01h
       int 21h
       push ax
       loop input
       pop  ax
       pop  bx
       pop  cx
       pop  dx
       push ax
       push bx
       push cx
       push dx
       mov  dx,offset m3
       mov  ah,09h
       int  21h
       mov  bh,4
text:
       cmp  bh,0
       je  EXIT
       dec  bh
       pop  ax
       mov  dx,ax
       SUB  AL,30H
       JL   error       ;输入其他字符
       CMP  AL,0AH
       JL   PRINT     ;输入0~9
       SUB  AL,07H
       CMP  AL,0AH
       JL   error       ;输入其他字符
       CMP  AL,0FH
       JLE  PRINT     ;输入A~F
       SUB  AL,20H              
       CMP  AL,0AH
       JL   error       ;输入其他字符
       CMP  AL,0FH
       JLE  PRINT     ;输入a~f
       JMP  error      ;输入其他字符 
PRINT: mov  cl,4
       mov  bl,al
       rol  bl,cl
       mov  cx,4
yj   : rol  bl,1
       mov  al,bl
       and  al,01h
       add  al,30h
       mov  dl,al
       mov  ah,02h
       int  21h
       loop yj
       jmp  text
error: mov dx,offset m2
       mov ah,09h
       int 21h
EXIT:  MOV  AH,4CH     ;程序结束并返回DOS
       INT  21H
CODE   ENDS
       END  START