title: Transfer data through audio jack cable over two Android devices
body: <p>I'm researching on transferring text data over male-to-male audio jack cable.</p>
  
  <p>I'm testing this on HTC one V and on PC, which supports male-to-male audio jack for data transfer as mentioned in <a href="http://en.wikipedia.org/wiki/Phone_connector_%28audio%29">this Wikipedia article</a>. It says:</p>
  
  <blockquote>
    <p>The first, which places the return signal on the second ring and the microphone on the sleeve, is used by Apple's iPhone line, HTC devices, latest Samsung, Nokia and Sony phones, among others.</p>
  </blockquote>
  
  <p>You can <a href="https://github.com/hitesh24by365/AudioJackTransfer">see my code here</a>.</p>
  
  <p>Problems I face during transfer: if I generate tone by entering any value from 0-31 at sender side, receiver will get actual value in 2-3 try due to the wrong type of FSK modulation/demodulation. Would you suggest the best error correction code that will help me out for correcting the input received from another Android device?</p>
  
  <p>If anyone has done this type of data transfer before, please suggest a code reference or some basic guidance regarding technical aspects, so I can complete this and make it open source for everyone.          </p>