NodeMCU ESP8266

FEATURES

• • Open-source
• • Interactive
• • Programmable
• • Low cost
• • Simple
• • Smart
• • WI-FI enabled

Arduino-like hardware IO

• • Advanced API for hardware IO, which can dramatically reduce the redundant work for configuring and manipulating hardware.
• • Code like arduino, but interactively in Lua script.

Nodejs style network API

• • Event-driven API for network applicaitons, which faciliates developers writing code running on a 5mm*5mm sized MCU in Nodejs style.
• • Greatly speed up your IOT application developing process.

Lowest cost WI-FI

• • Less than $2 WI-FI MCU ESP8266 integrated and esay to prototyping development kit.
• • We provide the best platform for IOT application development at the lowest cost.
  

SPECIFICATION

The Development Kit based on ESP8266, integates GPIO, PWM, IIC, 1-Wire and ADC all in one board.

Power your developement in the fastest way combinating with NodeMCU Firmware!

• USB-TTL included, plug&play
• 10 GPIO, every GPIO can be PWM, I2C, 1-wire
• PCB antenna

Code examples

The NodeMCU repository contains its own collection of elaborate code examples. Besides that the NodeMCU documentation provides small examples for most functions and modules.

Connect to an AP

print(wifi.sta.getip())
--nil
wifi.setmode(wifi.STATION)
wifi.sta.config{ssid="SSID",pwd="password"}
-- for older versions of the firmware wifi.sta.config("SSID","password")
-- wifi.sta.connect() not necessary because wifi.sta.config sets auto-connect = true
tmr.create():alarm(1000, 1, function(cb_timer)
  if wifi.sta.getip() == nil then
    print("Connecting...")
  else
    cb_timer:unregister()
    print("Connected, IP is "..wifi.sta.getip())
  end
end)

Control GPIO

ledPin = 1
swPin = 2
gpio.mode(ledPin,gpio.OUTPUT)
gpio.write(ledPin,gpio.HIGH)
gpio.mode(swPin,gpio.INPUT)
print(gpio.read(swPin))

HTTP request

-- A simple HTTP client
conn = net.createConnection(net.TCP, 0)
conn:on("receive", function(sck, payload) print(payload) end)
conn:on("connection", function(sck)
  sck:send("GET / HTTP/1.1\r\nHost: nodemcu.com\r\n"
          .. "Connection: keep-alive\r\nAccept: */*\r\n\r\n")
end)
conn:connect(80, "nodemcu.com")

Doing something similar using the HTTP module:

http.get("http://nodemcu.com", nil, function(code, data)
    if (code < 0) then
      print("HTTP request failed")
    else
      print(code, data)
    end
  end)

HTTP server

-- a simple HTTP server
srv = net.createServer(net.TCP)
srv:listen(80, function(conn)
    conn:on("receive", function(sck, payload)
        print(payload)
        sck:send("HTTP/1.0 200 OK\r\nContent-Type: text/html\r\n\r\n<h1> Hello, NodeMCU.</h1>")
    end)
    conn:on("sent", function(sck) sck:close() end)
end)

Connect to MQTT Broker

-- init mqtt client with keepalive timer 120sec
m = mqtt.Client("clientid", 120, "user", "password")

-- setup Last Will and Testament (optional)
-- Broker will publish a message with qos = 0, retain = 0, data = "offline"
-- to topic "/lwt" if client don't send keepalive packet
m:lwt("/lwt", "offline", 0, 0)

m:on("connect", function(con) print ("connected") end)
m:on("offline", function(con) print ("offline") end)

-- on publish message receive event
m:on("message", function(conn, topic, data)
  print(topic .. ":" )
  if data ~= nil then
    print(data)
  end
end)

-- for secure: m:connect("192.168.11.118", 1880, 1)
m:connect("192.168.11.118", 1880, 0, function(conn) print("connected") end)

-- subscribe topic with qos = 0
m:subscribe("/topic",0, function(conn) print("subscribe success") end)
-- or subscribe multiple topic (topic/0, qos = 0; topic/1, qos = 1; topic2 , qos = 2)
-- m:subscribe({["topic/0"]=0,["topic/1"]=1,topic2=2}, function(conn) print("subscribe success") end)
-- publish a message with data = hello, QoS = 0, retain = 0
m:publish("/topic","hello",0,0, function(conn) print("sent") end)

m:close();
-- you can call m:connect again

UDP client and server

-- a udp server
s=net.createServer(net.UDP)
s:on("receive",function(s,c) print(c) end)
s:listen(5683)

-- a udp client
cu=net.createConnection(net.UDP)
cu:on("receive",function(cu,c) print(c) end)
cu:connect(5683,"192.168.18.101")
cu:send("hello")