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Displaying numbers with DOS（1个答案）
Counting Hex in Assembly（2个答案）
6天前关闭
我在汇编8086中做了一个简单的加法计算器，当你在键盘上输入一个值时，它会把它们加起来。我可以把2+2加起来，得到正确的答案，但是当我把9+9加起来时，它输出的是B

.model small

.data
    message db "Enter a number: $" 
    message2 db 0xA, 0xD, "Enter another number: $" ; 0xA = new line, 0xD = carriage return, 0x24 = '$' 
    plus db " + $"
    equal db " = $"
.code
main proc  
    
    mov ax, seg message ; ax = message
    mov ds, ax          ; dx = ax = message
    mov dx, offset message 
    mov ah, 9h          ; output of a string at DS:DX
    int 21h   
    
    mov ah, 01h ; Read character (stores in al)
    int 21h
    
    mov bl, al  ; saving our input into bl
    
    mov ax, seg message
    mov ds, ax          ; dx = ax = message2
    mov ds, ax          ; dx = ax = message2
    mov dx, offset message2 
    mov ah, 9h          ; output of a string at DS:DX
    int 21h 
    
    mov ah, 1h ; Read character 
    int 21h
    
    mov cl, al ; stores 2nd input 
      
    ;mov dl, bl ; print 1st input
    ;mov ah, 02h ; Write character
    ;int 21h
    
    ; print + 
    mov ax, seg plus
    mov ds, ax
    mov dx, offset plus
    mov ah, 9h
    int 21h
    
    ; print 2nd number
    mov dl, cl
    mov ah, 02h
    int 21h  
    
    ; print =
    mov ax, seg equal
    mov ds, ax
    mov dx, offset equal
    mov ah, 9h
    int 21h
    
    ; This is were its having problems adding
    ; print sum
    sub bl, 48
    sub cl, 48
    add bl, cl
    mov dl, bl
    add dl, 48
    mov ah, 02h
    int 21h
    
    
endp
end main

我试着调试它，看看它在做什么，它做的一切都是正确的，但当它到达添加部分时，它会说0x12而不是0x9（当做9+9时）