汇编语言之大小写转换

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将datasg中的第一个字符转换为大写，第二个字符转换为小写

assume cs:codesg,ds:datasg

datasg segment

    db 'BsSIc'

    db 'iNFOrMAtiOn'

datasg ends

codesg segment

    start: mov ax,datasg

             mov ds,ax

             mov bx,0

             mov cx,5

      s:     mov al,[bx]

              and al,11011111B

              mov [bx],al

              inc bx

              loop s

              mov bx,5

              mov cx,11

       s0:   mov al,[bx]

               or al,00100000B

               mov [bx],al

               inc bx

               loop s0

               mov ax,4c00h

               int 21h

codesg ends

end start