我尝试在汇编中写减法但是当我尝试例如44-12结果是36. 我的代码如下所示：
org 100h
start:
mov ah, 09h
mov dx, First
int 21h
mov ah, 01h
int 21h
sub al,'0'
mov bl, 10
mul bl
mov [number1], al
mov ah, 01h
int 21h
sub al,'0'
add [number1], al
mov ah, 09h
mov dx, Second
int 21h
mov ah, 01h
int 21h
sub al,'0'
mov bl, 10
mul bl
mov [number2], al
mov ah, 01h
int 21h
sub al,'0'
add [number1], al
mov bx, [number2]
mov ax, [number1]
;**************************sum*******************************************
add ax,bx
mov bl, 10
div bl
mov ch,ah
mov ah, 09h
mov dx,nl
int 21h
add al, '0'
mov dl, al
mov ah,2
int 21h
add ch, '0'
mov dl, ch
mov ah, 2
int 21h
; ***************************sub***************************************
mov al, 0
mov cl, 0
mov ah, 0
mov ch, 0
mov bx, 0
mov dx, 0
mov dx, 27
mov ax, 73
mov bl, 0
mov bl, 10
sub ax,dx
div bl
mov ch,ah
mov ah, 09h
mov dx,nl
int 21h
add al, '0'
mov dl, al
mov ah,2
int 21h
add ch, '0'
mov dl, ch
mov ah, 2
int 21h
;++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
mov ah,0
int 16h
mov ax, 4C00h
int 21h
number1 dw 0
number2 dw 0
First db "first :",10,13,"$"
Second db 10,13,"sec :",10,13,"$"
nl db "",10,13,"$"
当我做
mov dx, 12
mov ax, 44
结果是正确的。我有一个问题
1.我的变量有什么问题[number1]和[number2]