2.asm

华工电信系汇编习题的编程实现

stack segment stack 'stack'
      dw 32 dup(?)
stack ends

data segment 
     DecIn db 6,0,6 dup(?)
     HexOut db 4 dup(?),'$'

data ends

code segment 
begin proc far
      assume ss:stack,cs:code,ds:data
      push ds
      sub ax,ax
      push ax
      mov ax,data
      mov ds,ax

      mov dx,offset DecIn
      mov ah,10
      int 21H
      
      mov ch,0
      mov cl,DecIn[1]
      mov SI,offset DecIn + 2
      mov ax,0
AGAIN:
      mov bx,10
      mul bx      
      mov dl,[SI]      
      sub dl,030H
      add ax,dx
      INC SI
      loop AGAIN

      mov SI,0
      mov bl,ah
      and bl,0F0H
      mov cl,4
      shr bl,cl
      CALL CHANGE
      mov HexOut[SI],bh
      INC SI

      mov bl,ah
      and bl,00FH
      CALL CHANGE
      mov HexOut[SI],bh
      INC SI

      mov bl,al
      and bl,0F0H
      mov cl,4
      shr bl,cl
      CALL CHANGE
      mov HexOut[SI],bh
      INC SI

      mov bl,al
      and bl,00FH
      CALL CHANGE
      mov HexOut[SI],bh
      
      mov dl,'='  
      mov ah,2
      int 21H
     
      mov dx,offset HexOut 
      mov bx,word ptr HexOut
      CMP bx,03030H
      JNZ ZERO
      add dx,2
ZERO:
      mov ah,9
      int 21H


      ret
begin   endp
CHANGE PROC
       CMP bl,0AH
       JB NUMBER
       add bl,7 
NUMBER:
       add bl,030H
       mov bh,bl      
       ret
CHANGE ENDP

code    ends
      end begin