title: One's twos compliment 8 bit signed magnitude, in binary
body: <p>So this was one of the questions in my textbooks, we haven't got there yet but i'm interested in how this all works,</p>
  
  <p>For the first bit here, my understanding of one's complement is you flip so where there are 1's you put 0's and 0's you put ones. This has to be 8 bit so i added a zero to the binary at the start 
  Therefre 01001001
  Write down the following binary representations of +73:</p>
  
  <pre><code>8-bit unsigned: 01001001
  8-bit signed-magnitude: 01001001
  8-bit one's complement: 10110110
  8-bit two's complement: 10110111
  8-bit excess-128: 10110111
  </code></pre>
  
  <p>These are the answers I came up with, but i'm fairly certain i did them wrongly. Any clarification on this?</p>
  
  <p>Secondly, how the heck to I do it with a negative so -73, the binary is just -01001001 so I assume that is the signed, do you do the same technique as above( assuming i have got them correct)</p>
  
  <pre><code>8-bit signed-magnitude: -01001001
  8-bit one's complement: 
  8-bit two's complement: 
  8-bit excess-128: 
  </code></pre>
  
  <p>Thanks in advance for any help</p>