title: How is a physical address generated in 8086?
body: <p>In the <em>8086</em> architecture, the memory space is 1 MiB in size and divided into logical segments of up to 64 KiB each.</p>
  
  <p>i.e. it has <strong>20</strong> address lines thus the following method is used:</p>
  
  <blockquote>
    <p>That the data segment register is shifted left 4 bits then added to the offset register </p>
  </blockquote>
  
  <p>My question is: How we do the shift operation although all the registers are only 16 bits</p>