C# Serial Port communication
<p>I'm trying to handle a serial port using the SerialPort class. </p>

<p>The application requires us receive one command first, and then give a reply in 20ms; the problem is, there is a delay(up to 15ms) between the command we read, and the actual command, and we don't have time to send the reply back.</p>

<p>The length of the command we need to read is fixed as 20 bytes, and we poll one byte from the input buffer each time.</p>

<pre><code>serialPort.Read(input, 0, 1).
</code></pre>

<p>I don't know what is wrong with this process.</p>
