;将每个字母都改为大写
assume cs:codesg,ds:datasg
datasg segment
db 'ibm '
db 'dec '
db 'dos '
db 'vax '
datasg ends
codesg segment
start:
mov ax,datasg
mov ds,ax
;bx for r , si for c
mov bx,0
mov cx,4
s0: mov dx,cx ;save the cx
mov si,0
mov cx,3
s: mov al,[bx+si]
and al,11011111b
mov [bx+si],al
inc si
loop s
mov cx,dx ;restore
add bx,10h
loop s0
mov ax,4c00h
int 21h
codesg ends
end start
;将每个字母都改为大写

最新推荐文章于 2019-12-12 16:18:39 发布