507.asm

来自「汇编语言的简单的输入字母的大小写转换的小汇编语言程序」· 汇编 代码 · 共 47 行

data segment
     j dw 1h,15h,4h,14h,25h,27h,6h,37h,44h,30 dup(5h,39h,4h),2h
     d dw 64h
data ends
code segment
     assume cs:code,ds:data
start:
       mov ax,data
       mov ds,ax
       mov si,-2
       mov dx,d   
next:  
       dec dx
       jz exit
       inc si          ;si表示数组元素下标
       inc si
       mov bx,j+[si]     
       test bx,1h
       jnz next
       mov ax,bx
       inc dx
       dec si 
next0:
       dec dx
       jz exit
       inc si
       inc si
       mov cx,j+[si]+1
       test cx,1h
       jnz next0
       cmp ax,cx        
       jnb next1
       jmp next0
next1:
       mov ax,cx
       jmp next0

exit:
       add ax,30h
       mov dl,al
       mov ah,2    
       int 21h
       mov ah,4ch
       int 21h
code ends
end start