title: How to turn off lua interpeter for uart? (Nodemcu)
body: <p>I need to communicate with a special device on uart. The device is queried in every 500msec, and its response is stored in a local variable.</p>
  
  <p>Here is a minimal working example:</p>
  
  <pre><code>my_data = "no data yet"
  
  function devReq()
      uart.write(0, "value?\n\r") -- request next value from device
  end
  
  function devStart()
      uart.alt(0) 
      uart.setup(0, 2400, 7, uart.PARITY_NONE, uart.STOPBITS_2, 0)
      uart.on("data", "\r", 
          function(data)
              my_data=data                -- store value
              tmr.alarm(1, 500, tmr.ALARM_SINGLE, devReq, 0) -- request next value
          end
      )
      devReq() -- request first value 
  end
  </code></pre>
  
  <p>This code works. I can connect do the uart port with putty. My problem is that the answer sent back by the device is also interpreted by lua:</p>
  
  <pre><code>&gt; value?
  
  423
  stdin:1: unexpected symbol near '423'
  
  &gt; value?
  
  2345
  stdin:1: unexpected symbol near '2345'
  
  &gt; value?
  </code></pre>
  
  <p>So in addition of storing the value in my_data, the data is also interpreted by lua. How can I turn that off?</p>