title: send AT command using adb shell
body: <p>I need to send AT command to modem. I am using samsung galaxy S3 I9300 device, which is rooted.</p>
  
  <p>The steps I did are:</p>
  
  <pre><code>abd shell
  su
  echo -e "AT\r"
  </code></pre>
  
  <p>But I am not sure how to read the response given by the above commands. I tried to redirect the command as follows:
  <code>echo -e "AT\r" &gt; /dev/smd0</code>, but when I execute cat <code>/dev/smd0</code> I do not see any response I just see "AT". Seems like the command I intended to be executed is interpreted just as string and I see that string instead of the result of that operation.</p>
  
  <p>Please advice what am I doing wrong.</p>