title: How to use the ADD instruction with SIGNED integers in Assembly 8086?
body: <p>So if I wanted to add two unsigned ints I would simply write</p>
  
  <pre><code>dat1 db ff
  dat2 db ff
  res dw ?
  </code></pre>
  
  <p>and in the code segment:</p>
  
  <pre><code>mov ax, dat1
  add ax, dat2
  mov dl,0
  adc dl,0 ;initialize the contents of dl and use it to store the carry flag
  mov byte ptr res, ax
  mov byte ptr res+1, dl
  </code></pre>
  
  <p>BUT, what would the code look like if I wanted to add two SIGNED integers? Can I somehow access the sign flag?</p>