specifies the port number. Ports are numbered starting from 0. There are
usually 0, 1 or 2 serial ports. There is also an optional
<code>type</code> attribute <span class="since">since 1.0.2</span>
- which has two choices for its value, one is< code>isa-serial</code>,
+ which has two choices for its value, one is <code>isa-serial</code>,
the other is <code>usb-serial</code>. If <code>type</code> is missing,
<code>isa-serial</code> will be used by default. For <code>usb-serial</code>
an optional sub-element <code><address></code> with