实验10

assume  cs:code, ds:data
data segment
    db 'Welcome to masm!', 0
data ends

code segment
       start:  mov dh, 8
               mov dl, 3
               mov cl, 2
               mov ax, data
               mov ds, ax
               mov si, 0
               call  show_str
              

               mov ah, 1
               int 21h
               mov ax, 4c00h
               int 21h
              

         show_str:
                  push ax
                  push bx
                  push es
                  push si
                  mov ax, 0b800h
                  mov es, ax
                  mov ax, 160
                  mul dh ; ax = 160 * dh
                  mov bx, ax  ; save ax
                  mov ax, 2
                  mul dl  ; ax = dl * 2
                  add bx, ax ; bx = (160 * dh + 2 * dl) head address
                  mov al, cl
                  mov cl, 0
          show0:

                  mov ch, [si]
                  jcxz show1
                  mov es:[bx], ch
                  mov es:[bx].1, al
                  inc si
                  add bx, 2
                  jmp show0
          show1:
                  pop si
                  pop es
                  pop bx
                  pop ax
                  ret
                 

code ends

end start