samples/gcd-input.asm

   1 .model      small
   2 ;greatest common divisor, with input from terminal
   3 data segment
   4   tempStr db "        "
   5   prompt  db "num?$"
   6   promptr db "RES $"
   7   m     dw  0
   8   n     dw  0
   9
  10 data ends
  11 ;#macros-removed-from-listing
  12
  13 .code
  14
  15 start:
  16     mov ax,@data
  17     mov ds,ax
  18     print_str prompt
  19     read_num m
  20     print_new_line
  21     print_str prompt
  22     read_num n
  23     print_new_line
  24
  25             mov   ax,n
  26             mov   bx,m
  27
  28 compare:
  29             cmp   ax,bx
  30             je    exit ;exit since they're equal
  31             ja    greater
  32             sub   bx,ax
  33             jmp   compare
  34
  35 greater:
  36             sub   ax,bx
  37             jmp   compare
  38
  39 exit:
  40 ;exit out of the program
  41     mov n,ax
  42     print_str promptr
  43         print_num n
  44 ; print out a result
  45             end_execution
  46
  47 .stack
  48 end start