1.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 
     OutBuf1 db 'Please input the num:$'
     OutBuf2 db 'The Reslut is:$'
     DecIn db 7,0,7 dup(?)
     HexOut db 5 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 OutBuf1
      mov ah,9
      int 21H
      
      mov dx,offset DecIn
      mov ah,10
      int 21H
    
      mov dl,00AH
      mov AH,2
      int 21H
  
      mov ch,0
      mov cl,1[DecIn]     
      mov SI,offset DecIn + 2
      mov ax,0
      CMP byte ptr [SI],'-'
    pushf      
      JNZ NEXT
      INC SI
      DEC cx       
NEXT:
      mov bl,[SI]
      sub bl,30H
      mov bh,0
      mov dx,10
      mul dx
      add ax,bx 
      INC SI
      loop NEXT            

    popf
    mov DI,0
    JNZ ZHENG
    add ax,8000H
    NEG ax
    add ax,8000H 

ZHENG:
    mov bl,ah
    and bl,0F0H
    mov cl,4
    shr bl,cl
    CALL CHANGE
    mov HexOut[DI],bl
    INC DI 

    mov bl,ah
    and bl,00FH
    CALL CHANGE
    mov HexOut[DI],bl
    INC DI 
 
    mov bl,al
    and bl,0F0H
    mov cl,4
    shr bl,cl
    CALL CHANGE 
    mov HexOut[DI],bl
    INC DI  

    mov bl,al
    and bl,00FH
    CALL CHANGE
    mov HexOut[DI],bl  
    INC DI 

    mov HexOut[DI],'$'
    mov dx,offset HexOut
    mov bx,word ptr HexOut
    CMP bx,03030H
    JNZ THEN
    add dx,2
THEN:
    mov ah,9
    int 21H

    ret
begin   endp

CHANGE PROC
    CMP bl,00AH
    JS NUM
    add bl,7 
NUM:
    add bl,30H

MYEND:
    ret
CHANGE ENDP

code    ends
      end begin