title: Measurement Time Delay - Raspberry Pi 3B, Python, MQ Sensor, Websockets
body: <p>i use a Raspberry Pi 3B (RPi) and a MQ-Sensor, which is wired to a A/D Converter (I2C to RPi), to measure profiles of gases. The RPi is connected to an Android system via Lan. The Android System is used for controlling the running measurement program on the RPi. They communicate via websockets. I deactived DHCP on the RPi and gave it a fixed IP etc..</p>
  <p>The Pi has to send a value every second to the Android device. I used the time.sleep() command, to wait 1s and send the data.</p>
  <p><strong>The problem:</strong> My measurement has a time delay. For example the real time was 60min, the measurement is 50min long. So it seems, that the RPi uses bigger time steps between the measurement points.</p>
  <p><strong>My question:</strong> Is the time delay caused by the disconnection between the RPi and the Internet? I recognized, that the system time of the RPi is also delayed. Could it be, that the time.sleep() function does not work correctly if the RPi has no internet connection?</p>
  <p>I hope, that you could help me.</p>
  <p>Best wishes</p>