Question

有人会给我一个microASM程序，它将乘以用户给出的2个值吗？我正在为我的参考资料做一些研究。

更新：这是我尝试的代码，但它通过了无穷大

#make_COM#

; COM file is loaded at CS:0100h
ORG 100h

DATA SEGMENT
    NUM1 DB ?
    NUM2 DB ?
    RESULT DB ?
    MSG1 DB 10,13,"ENTER FIRST NUMBER: $"
    MSG2 DB 10,13,"ENTER SECOND NUMBER: $"
    MSG3 DB 10,13,"rESULT OF MULTIPLICATION IS: $"
DATA ENDS

CODE SEGMENT
    ASSUME DS:DATA CS:CODE
START:
    MOV AX,DATA
    MOV DS,AX

    LEA DX,MSG1
    MOV AH,9
    INT 21H

    MOV AH,1
    INT 21H
    SUB AL,30H
    MOV NUM1,AL

    LEA DX,MSG2
    MOV AH,9
    INT 21H

    MOV AH,1
    INT 21H
    SUB AL,30H
    MOV NUM2,AL

    MUL NUM1

    MOV RESULT,AL
    AAM

    ADD AH,30H
    ADD AL,30H

    MOV BX,AX

    LEA DX,MSG3
    MOV AH,9
    INT 21H

    MOV AH,2
    MOV DL,BH
    INT 21H

    MOV AH,2
    MOV DL,BL
    INT 21H

    MOV AH,4CH
    INT 21H
CODE ENDS
END START

Answer 1

好的，Karl Reyes，你要求一个程序来乘以用户给出的两个值。下一个程序正是这样做的。它是用EMU8086制作的，它已被完全评论以帮助您理解它。只需复制，粘贴并运行：

.stack 100h
;------------------------------------------
.data
;------------------------------------------
msj1  db 'Enter first number: $'
str1  db 6 ;MAX NUMBER OF CHARACTERS ALLOWED (4).
      db ? ;NUMBER OF CHARACTERS ENTERED BY USER.
      db 6 dup (?) ;CHARACTERS ENTERED BY USER. 
num1  dw ?     
msj2  db 13,10,13,10,'Enter second number: $'
str2  db 6 ;MAX NUMBER OF CHARACTERS ALLOWED (4).
      db ? ;NUMBER OF CHARACTERS ENTERED BY USER.
      db 6 dup (?) ;CHARACTERS ENTERED BY USER. 
num2  dw ?          
prod  dw ? ;NUM1 * NUM2.
msj3  db 13,10,13,10,'Product : $'
str3  db 7 dup('$')
;------------------------------------------
.code          
;INITIALIZE DATA SEGMENT.
  mov  ax, @data
  mov  ds, ax
;------------------------------------------        
;DISPLAY MESSAGE.
  mov  ah, 9
  mov  dx, offset msj1
  int  21h
;CAPTURE NUMBER 1 AS STRING.
  mov  ah, 0Ah
  mov  dx, offset str1
  int  21h
;------------------------------------------        
;DISPLAY MESSAGE.
  mov  ah, 9
  mov  dx, offset msj2
  int  21h
;CAPTURE NUMBER 2 AS STRING.
  mov  ah, 0Ah
  mov  dx, offset str2
  int  21h
;------------------------------------------
;CONVERT CAPTURED NUMBERS (STRINGS) TO REAL NUMBERS.
  mov  si, offset str1 ;PARAMETER FOR STRING2NUMBER.
  call string2number
  mov  num1, bx ;RETURNED VALUE.

  mov  si, offset str2 ;PARAMETER FOR STRING2NUMBER.
  call string2number
  mov  num2, bx ;RETURNED VALUE.
;------------------------------------------
;MULTIPLY.
  mov  ax, num1
  mul  num2 ;AX * NUM2. RESULT IN DX:AX.
;------------------------------------------
;DISPLAY RESULT. IGNORE DX, ASSUMING RESULT FITS IN AX.
  call number2string ;TAKES AX AS PARAMETER.

  mov  ah, 9
  mov  dx, offset msj3
  int  21h

  mov  ah, 9
  mov  dx, offset str3
  int  21h
;------------------------------------------
;WAIT UNTIL USER PRESS ANY KEY.
  mov  ah,7
  int  21h
;------------------------------------------
;FINISH THE PROGRAM PROPERLY.
  mov  ax, 4c00h
  int  21h           
;------------------------------------------
;NUMBER TO CONVERT MUST ENTER IN AX.
;ALGORITHM : EXTRACT DIGITS ONE BY ONE, STORE
;THEM IN STACK, THEN EXTRACT THEM IN REVERSE
;ORDER TO CONSTRUCT STRING.
proc number2string
  mov  bx, 10 ;DIGITS ARE EXTRACTED DIVIDING BY 10.
  mov  cx, 0 ;COUNTER FOR EXTRACTED DIGITS.
cycle1:       
  mov  dx, 0 ;NECESSARY TO DIVIDE BY BX.
  div  bx ;DX:AX / 10 = AX:QUOTIENT DX:REMAINDER.
  push dx ;PRESERVE DIGIT EXTRACTED FOR LATER.
  inc  cx ;INCREASE COUNTER FOR EVERY DIGIT EXTRACTED.
  cmp  ax, 0  ;IF NUMBER IS
  jne  cycle1 ;NOT ZERO, LOOP. 
;NOW RETRIEVE PUSHED DIGITS.
  mov  si, offset str3
cycle2:  
  pop  dx        
  add  dl, 48 ;CONVERT DIGIT TO CHARACTER.
  mov  [ si ], dl
  inc  si
  loop cycle2  

  ret
endp  
;------------------------------------------
;CONVERT STRING TO NUMBER IN BX.
;SI MUST ENTER POINTING TO THE STRING.
proc string2number
;MAKE SI TO POINT TO THE LEAST SIGNIFICANT DIGIT.
  inc  si ;POINTS TO THE NUMBER OF CHARACTERS ENTERED.
  mov  cl, [ si ] ;NUMBER OF CHARACTERS ENTERED.                                         
  mov  ch, 0 ;CLEAR CH, NOW CX==CL.
  add  si, cx ;NOW SI POINTS TO LEAST SIGNIFICANT DIGIT.
;CONVERT STRING.
  mov  bx, 0
  mov  bp, 1 ;MULTIPLE OF 10 TO MULTIPLY EVERY DIGIT.
repeat:         
;CONVERT CHARACTER.                    
  mov  al, [ si ] ;CHARACTER TO PROCESS.
  sub  al, 48 ;CONVERT ASCII CHARACTER TO DIGIT.
  mov  ah, 0 ;CLEAR AH, NOW AX==AL.
  mul  bp ;AX*BP = DX:AX.
  add  bx,ax ;ADD RESULT TO BX. 
;INCREASE MULTIPLE OF 10 (1, 10, 100...).
  mov  ax, bp
  mov  bp, 10
  mul  bp ;AX*10 = DX:AX.
  mov  bp, ax ;NEW MULTIPLE OF 10.  
;CHECK IF WE HAVE FINISHED.
  dec  si ;NEXT DIGIT TO PROCESS.
  loop repeat ;COUNTER CX-1, IF NOT ZERO, REPEAT.

  ret 
endp

让我知道它是否适合你。

有人会给我一个microASM程序，它将乘以用户给出的2个值吗？

1 个答案: