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<a name="overview"></a><hr>
<center><h1>UDP driver</h1></center>
<p>
The udp driver supports receiving mode2 input via UDP.</p>
<p>
Received UDP packets consist of a number of little endian 16-bit integers.
The high bit signifies the state of the received signal; set indicates a
mark, clear a space. The low 15 bits specify how long the signal lasted.</p>
<p>
With the default resolution setting (61) the times are measured in 1/16384
second intervals. This was used by old hardware using a cheap 32kHz clock
crystal, when designing new devices a 1MHz 1µs clock is recommended.</p>
<p>
To allow long times to be transfered a long UDP input format is available,
this consists of a zero time as specified by the short format followed by
a four byte little endian time value. This should only be needed occasionally
for example the time between button presses.</p>
<p>
The UDP port can be set using the `--device=port` or `-d port` command line
switch. In the time of writing, there is no way to specify the interface to
use - the driver will listen to all interfaces.</p>
<p>
The timing resolution can be set using the `--driver-option=clocktick:value`
or `-A clocktick:value` command line switch e.g.,
</p>
<pre>
mode2 --driver=udp --device=8766 --driver-option=clocktick:1
</pre>
to use port 8766 and 1 microsecond timing resolution.
<p>
<em>Note:</em> Little endian is not conventional network byte order. </p>
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