title: AT Commands CMGS return ERROR
body: <p>I am using Prolink PSH300 HSUPA GSM Modem connect to my laptop and using tera term to test the connect. </p>
  
  <p>First I entered AT it will response me OK </p>
  
  <p>AT 
  OK </p>
  
  <p>AT+CMGF=1 
  OK </p>
  
  <p>AT+CMGS="+6581XXXXXX" (then I pressed enter error was returned) 
  ERROR </p>
  
  <p>Sometime it won't return me error but just hang there no > return. </p>
  
  <p>Could anybody advise me what to do?</p>