title: Append part of byte to another byte
body: <p>I want to take the first 4 bits of one byte and all bits of another bit and append them to eachother.<br>
  This is the result I need to achieve: </p>
  
  <p><img src="https://i.stack.imgur.com/wJPxp.png" alt="enter image description here"><br>
  This is what I have now:</p>
  
  <pre><code>private void ParseLocation(int UpperLogicalLocation, int UnderLogicalLocation)
  {
      int LogicalLocation = UpperLogicalLocation &amp; 0x0F;   // Take bit 0-3
      LogicalLocation += UnderLogicalLocation;
  }
  </code></pre>
  
  <p>But this is not giving the right results. </p>
  
  <pre><code>int UpperLogicalLocation_Offset = 0x51;
  int UnderLogicalLocation = 0x23;
  
  int LogicalLocation = UpperLogicalLocation &amp; 0x0F;   // Take bit 0-3
  LogicalLocation += UnderLogicalLocation;
  
  Console.Write(LogicalLocation);
  </code></pre>
  
  <p>This should give  0x51(0101<strong>0001</strong>) + 0x23 (00100011),<br>
  So the result I want to achieve is 0001 + 00100011 = 000100100011 (0x123)</p>