NodeMCU - IoT on the Cheap

-___-.md

Linux

Windows

ESP8266 Flasher
LUA Loader 

Mac / Linux

esptool
UART Driver
esplorer 

Command-line to flash firmware

esptool.py -p /dev/ttyUSB0 write_flash 0x000000 Downloads/nodemcu.bin

NodeMCU Firmware Binary

nodemcu-dev-14-modules-2015-11-02-23-45-27-float.bin 

Sample LUA Scripts

Rename either one of these files to init.lua and upload it to the NodeMCU board.

• First Wifi Demo (rename to init.lua)
• Web Server Sample

Other Resources

• NodeMCU Custom Builds
• Buy more of the DEV boards, ~$4 inlcuding shipping

get_ip.lua

-- Set up WiFI
wifi.setmode(wifi.STATION)
wifi.sta.config("", "")

-- Tell us when we've gotten an IP
tmr.alarm(0, 500, 1, function()
   if wifi.sta.getip()==nil
    then
      print("Connecting to AP...")
   else
      print("Connected as: " .. wifi.sta.getip())
      tmr.stop(0)
   end
end)

webserver.lua

print("STARTING UP")
wifi.setmode(wifi.STATION)
wifi.sta.config("Hacklab-Guests","")

led1 = 5
gpio.mode(led1, gpio.OUTPUT)

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+)=([^&]+)&*") do
                _GET[k] = v
            end
        end
        buf = buf.."<h1>ESP8266 Web Server</h1>";
        buf = buf.."<p>Output 5 <a href=\"?set1=on\"><button>ON</button></a>&nbsp;<a href=\"?set1=off\"><button>OFF</button></a></p>";
        local _on,_off = "",""
        if(_GET.set1 == "on") then gpio.write(led1, gpio.HIGH); end
        if(_GET.set1 == "off") then gpio.write(led1, gpio.LOW); end

		WebResponse(client, buf);
        collectgarbage();
    end)
end)

function WebResponse(client, buf)
	local hd = "HTTP/1.1 200 OK\r\n"
	hd=hd.."Server: AvESP 0.1\r\n"
	hd=hd.."Content-Length: "..string.len(buf).."\r\n"
	hd=hd.."Content-Type: text/html\r\n"
	hd=hd.."\r\n"
	client:send(hd..buf)
	client:close()
end