title: STM32 wake up from standby by RTC
body: <p>I am programming STM32L051R8 and have next problem. I'm trying use standby mode in most part of time, and sometimes wake up by RTC, it is an auto wake-up. If I work without sleep - all works perfectly, I got an RTC interrupt every time, but when I use standby - don't.</p>
  
  <p>If I use standby, I have a good first cycle:</p>
  
  <ol>
  <li>reset</li>
  <li>set RTC</li>
  <li>enter standby</li>
  <li>waiting for interrupt</li>
  <li>wake-up</li>
  </ol>
  
  <p>But second and next cycles wake up immediately after entering standby (3). </p>