CSC 6Fh Programming assignment 1

   	                 Due Wednesday 2/20/2002



  Use MASM to write a program to read in a string and print the string
backwards.

  You may use either interrupt 21h, function 01h to read characters one
at a time until return is read (code 0dh), or use function 0Ah, which 
reads an entire line automatically.  For output I recommend function 02h,
which prints one char at a time.  Consult book and web page for further
documentation on using the interrupts.

  To invoke a certain function for interrupt service 21h, you have to put
the function number in register ah, as in:

  mov ah,01
  int 21h

  This will read in a single char and store it in register al.

  What if you're using the ax register for another purpose before you need
to call the interrupt?  You need to save the value of ax somewhere before
you use it for the purpose of reading a char:

  push ax
  mov ah,01
  int 21h
  pop ax ; ax now restored to original value!


You should store the string read into a buffer in the .data section.