title: How to check if the PIN has a certain value
body: <p>I'm developing on a mobile gsm platform and I need to know the PIN in order to change it. Is there a way to verify if the <a href="http://en.wikipedia.org/wiki/Personal_identification_number" rel="nofollow">PIN</a> has a certain value?</p>
  
  <p>I'm looking for the solution that makes use of <a href="http://en.wikipedia.org/wiki/Hayes_command_set" rel="nofollow">AT commands</a> since this is the only way to control the gsm modem.</p>
  
  <p>I need this to prevent the use of the SIM card for data transfer, calls etc in personal phones or other devices.</p>
  
  <p>Is there a simple way to find out what the PIN is (highly unlikely) or to check if the PIN is the one from a list of expected values?</p>
  
  <p>Thanks</p>