王爽汇编第二册:将每个单词的前四位改为大写字母

1  问题描述

2 汇编代码

assume cs:codesg,ss:stacksg,ds:datasgstacksg segment  dw 0,0,0,0,0,0,0,0stacksg endsdatasg segment db '1.display#######' db '2.brows#########' db '3.replace#######' db '4.modify########'datasg endscodesg segment start:mov ax,stacksg       mov ss,ax       mov sp,16   mov cx,4   mov si,datasg   mov ds,si   mov si,0  s1:  push cx       mov cx,4       mov bx,0   s2: mov al,[si+bx+2]       and al,11011111b   mov [si+bx+2],al   add bx,1       loop s2       pop cx       add si,16   loop s1   mov ah,9   int 21hcodesg endsend start