View source for ESP8266 Controlled Door Operator

[[Image:Door_operator_swing_door.jpg|600px]]
At our office building, there is a Dorma [http://www.dorma.com/us/en/products/opening_closing/automatic_swing_door_operators/ed100_250_ansi/index-144-470-2757.html Automatic Swing Door Operator] which is normally engaged by a push button next to the door frame and also wirelessly from the hall way end of the door.

Pressing and waiting for the door to open is unbearable, therefore I made the decision to add a third option to the mix; operating it wirelessly from my mobile phone using the web browser. 

== Digital switch ==

The way the wired and wireless buttons are wired on the automatic door operator is fairly simple, just ground and a control signal which is pulled high (24V). Pull this control line low and the door will engage and begin to swing open.

Adding a third option is just a matter of adding a transistor between the control signal and ground; and having a controller toggle the transistor when needed.

== Schematic ==
[[Image:Door_operator_schematic.png|600px]]

The system is based on a 3.3V regulator (although I used my own ESP8266 breakout board which has a 3.3V regulator, connected to a 5V regulator capable of handling 24V in), the main ESP8266-ESP01 board and a pair of PNP and NPN transistors.

== Code ==
The code is based on Lua for NodeMCU. This code is just a sample web server code modified to wait 500ms before releasing the pull-low event.

<pre>
wifi.setmode(wifi.STATION)
wifi.sta.config("WIFISSID","WIFIPASSWD")
print(wifi.sta.getip())
led1 = 3
led2 = 4
gpio.mode(led1, gpio.OUTPUT)
gpio.write(led1, gpio.LOW);
gpio.mode(led2, gpio.OUTPUT)
gpio.write(led2, gpio.LOW);
srv=net.createServer(net.TCP)
srv:listen(80,function(conn)
    conn:on("receive", function(client,request)
        local buf = "";
        local _, _, method, path, vars = string.find(request, "([A-Z]+) (.+)?(.+) HTTP");
        if(method == nil)then
            _, _, method, path = string.find(request, "([A-Z]+) (.+) HTTP");
        end
        local _GET = {}
        if (vars ~= nil)then
            for k, v in string.gmatch(vars, "(%w+)=(%w+)&*") do
                _GET[k] = v
            end
        end
        buf = buf.."HTTP/1.1 200 OK\nCache-Control: no-cache, no-store, must-revalidate\nPragma: no-cache\nExpires: 

0\n\n";
        buf = buf.."<html><head><title>ESP8266 Srv</title></head><body><h1>ESP8266 Web Server</h1>";
        buf = buf.."<p>GPIO0 <a href=\"?pin=ON1\"><button>ON</button></a>&nbsp;<a 

href=\"?pin=OFF1\"><button>OFF</button></a></p>";
        buf = buf.."<p>GPIO2 <a href=\"?pin=ON2\"><button>ON</button></a>&nbsp;<a 

href=\"?pin=OFF2\"><button>OFF</button></a></p>";
        buf = buf.."</body></html>";
        local _on,_off = "",""
        if(_GET.pin == "ON1")then
          gpio.write(led1, gpio.HIGH);
          tmr.delay(500000);
          gpio.write(led1, gpio.LOW);
          elseif(_GET.pin == "OFF1")then
              gpio.write(led1, gpio.LOW);
              elseif(_GET.pin == "ON2")then
        	  gpio.write(led2, gpio.HIGH);
        	  tmr.delay(500000);
		  gpio.write(led2, gpio.LOW);
                  elseif(_GET.pin == "OFF2")then
                      gpio.write(led2, gpio.LOW);
                  end
                  client:send(buf);
                  client:close();
                  collectgarbage();
                  end)
end)

</pre>

== Installed ==
The installation process is as simple as it get. Just figure out how the existing buttons are wired and find a power&gnd lane to power everything. Luckly, the wireless module for the door was also powered by 24V so all three necessary pins were next to each other. To easy removal, I did not screw the wires into the block but just stuck them into the right terminal.

[[Image:Door_operator_installed.jpg|600px]]

There was lots of room in the back of the unit to mount everything. This is the area where the cables from the buttons and sensors came in, so just a little re-jiggling was needed.

== Working ==

This shows the screen of an iPhone operating the webserver. Opening the door is as easy as just toggling the button. By making a shortcut on the home-screen directly to the toggling URL makes it even easier to engage.

== References ==
* [http://randomnerdtutorials.com/esp8266-web-server/ ESP8266 web server]