p244_2.asm

王爽汇编语言的课件

assume cs:code
code segment

start:mov ax,cs
	mov ds,ax
	mov si,offset capital
	mov ax,0
	mov es,ax
	mov di,200h
	mov cx,offset capitalend - offset capital
	cld
	rep movsb

	mov ax,0
	mov es,ax
	mov word ptr es:[7ch*4],200h
	mov word ptr es:[7ch*4+2],0

	mov ax,4c00h
	int 21h

  capital:
	push cx
	push si
change: mov cl,[si]
	mov ch,0
	jcxz ok
	and byte ptr [si],11011111b
	inc si
	jmp short change
ok:	pop si
	pop cx
	iret
capitalend:nop

code ends
end start