title: Espressif Wifi not connecting or showing AP
body: <p>First of all, I won't go into details, cause there are a lot of them, and I dont want to write (a too long) essay. There is TL;DR section at the end, because I have a specific question, but maybe some additional info can help.</p>
  
  <p>I have a device that is made of a GRU (glass room unit) and espressif (esp8266).</p>
  
  <p>GRU and esp8266 communicate via serial, with GRU as master. GRU is programmed with an internal tool, and I can monitor everything on it, including the info it gets from esp8266.
  There is a test/development device, that has espressif on top of the GRU, so I can easily take it off, reprogram/reconfigure it, and put it on.</p>
  
  <p>Espressif is inside of a GRU, and downloading stuff to flash is a real pain. There is whole process including a OS switch (from Win7 to Linux and back). Console output on espressif cannot be done, or at least not in the time frame I have.</p>
  
  <p>For esp8266 I use non-os SDK V2.0.0_16_08_10.</p>
  
  <p>Espressif can be configured with downloading a configuration to flash, or via UDP (over a network if connected, over its AP if its not connected).</p>
  
  <p>Algorithm for Wifi:</p>
  
  <pre><code> 1. Try to connect to a network from configuration
   2. If it succeeds, raise a flag for that
   3. If it fails, enter dual (STATION+AP) mode and raise a flag for that
  </code></pre>
  
  <p>The reason espressif is not always in dual mode is that it affects multi-cast operations.</p>
  
  <p>Configuration over network is done by a Java aplication I wrote.</p>
  
  <p>Scenario 1</p>
  
  <p>I've configured a wifi router, configured all (x19) of the devices (espressif in devices that is) to connect to its network. When I turned them on, they would connect one by one. The ones that didn't entered dual mode and could be configured via the app.</p>
  
  <p>All well.</p>
  
  <p>Scenario 2
  I've wanted to test the system in real world, so I reconfigured them to connect to the our firms network. Additionally when I was already going thru the whole process I've downloaded latest firmare to flash.</p>
  
  <p>I expected that they would connect or enter dual mode and create their own APs. But they did not.</p>
  
  <p>I tested then the code and configuration on espressif whose console output I could monitor, and everything worked.</p>
  
  <p>I tested then the code and configuration on the test device, and it worked again.</p>
  
  <p>I've then redownloaded the code and configuration to one device, and it didn't work.</p>
  
  <p>TL;DR
  I have two devices, espressif on a GRU and espressif inside of a GRU. Both connected to one network. Esp on a GRU work for another, Esp inside of a GRU doesn't work for that other network.
  They have identical code and configuration, so it shouldn't be a software issue.</p>
  
  <p>Does having espressif inside of a device jams its signal enough that it can't go trough? Device is not big (5x5x2cm).</p>
  
  <p>UPDATE 1:
  While I was writing, the espressif inside of a GRU managed to connect to network. I then restarted it so I can check that it can do it again, and it can't connect again.
  It took me about 10 minutes to write the whole question.</p>