p117.asm

assume cs:code

data segment
  ;db    '0123456789ABCDEF'
  db     '1. file         '
  db     '2. edit         '
  db     '3. view         '
  db     '4. tool         '
  db     '5. help         '
data ends

stack segment stack
  dw 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
  dw 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
stack ends

;and al, 11011111B


code segment
start:
  mov ax, stack
  mov ss, ax
  mov sp, 64
  
  mov ax, data
  mov ds, ax
  mov bx, 0
  mov cx, 5

upAll:
  push cx
  mov si, 0
  mov cx, 4
upByte:
  mov al, ds:[bx + si + 3]
  and al, 11011111B
  mov ds:[bx + si + 3], al
  inc si
  loop upByte

  pop cx
  add bx, 16
  loop upAll

  mov ax, 4c00h
  int 21h

code ends

end start