This tutorial will discuss get the google time using NodeMCU in ESP8266. The ESP8266 NodeMCU is a popular development board known for its versatility and ease of use in Internet of Things (IoT) projects. In this tutorial, we’ll explore how to leverage the ESP8266 NodeMCU to fetch the current time from Google’s time servers. Accurate timekeeping is crucial for many IoT applications, such as data logging, scheduling tasks, and synchronization across multiple devices. By connecting to Google’s time servers, we can ensure that our ESP8266 NodeMCU has access to precise and reliable time information.

Code for Get Google Time using NodeMCU in ESP8266

• You can use any server instead of google. But that server should install http server
• Use conn:connect(80,”google.com”)   or Google static ip address conn:connect(80,”64.233.161.94″)

-- https://www.aruneworld.com/embedded/espressif/esp8266/esp8266_nodemcu/
-- Tested By  : Arun(20170219)
-- Example Name : AEW_GoogleTime.lua

station_cfg={}
station_cfg.ssid= "Arun" station_cfg.pwd= "ArunEworld" -- Change your SSID and Password
wifi.setmode(wifi.STATIONAP)
wifi.sta.config(station_cfg)
wifi.sta.connect()

wifi.eventmon.register(wifi.eventmon.STA_CONNECTED, function(T)
print("\n\tSTA - CONNECTED".."\n\tSSID: "..T.SSID.."\n\tBSSID: "..T.BSSID.."\n\tChannel: "..T.channel)

end)
wifi.eventmon.register(wifi.eventmon.STA_DISCONNECTED, function(T)
  print("\n\tSTA - DISCONNECTED".."\n\tSSID: "..T.SSID.."\n\tBSSID: "..T.BSSID.."\n\treason: "..T.reason)
end)
wifi.eventmon.register(wifi.eventmon.STA_GOT_IP, function(T)
  print("\n\tSTA - GOT IP".."\n\tStation IP: "..T.IP.."\n\tSubnet mask: "..T.netmask.."\n\tGateway IP: "..T.gateway)
  sta_ip = T.IP
end)



wifi.eventmon.register(wifi.eventmon.STA_CONNECTED, function(T)
print("\n\tSTA - CONNECTED".."\n\tSSID: "..T.SSID.."\n\tBSSID: "..T.BSSID.."\n\tChannel: "..T.channel)

end)
wifi.eventmon.register(wifi.eventmon.STA_DISCONNECTED, function(T)
  print("\n\tSTA - DISCONNECTED".."\n\tSSID: "..T.SSID.."\n\tBSSID: "..T.BSSID.."\n\treason: "..T.reason)
end)
wifi.eventmon.register(wifi.eventmon.STA_GOT_IP, function(T)
  print("\n\tSTA - GOT IP".."\n\tStation IP: "..T.IP.."\n\tSubnet mask: "..T.netmask.."\n\tGateway IP: "..T.gateway)
  sta_ip = T.IP
end)



conn=net.createConnection(net.TCP, 0) 

conn:on("connection",function(conn, payload)
            conn:send("HEAD / HTTP/1.1\r\n".. 
                      "Host: google.com\r\n"..
                      "Accept: */*\r\n"..
                      "User-Agent: Mozilla/4.0 (compatible; esp8266 Lua;)"..
                      "\r\n\r\n") 
            end)
            
conn:on("receive", function(conn, payload)
    print('\nRetrieved in '..((tmr.now()-t)/1000)..' milliseconds.')
    print('Google says it is '..string.sub(payload,string.find(payload,"Date: ")
           +6,string.find(payload,"Date: ")+35))
    conn:close()
    end) 
t = tmr.now()    
conn:connect(80,'google.com')
tmr.alarm(0,10000,1,function() conn:connect(80,'google.com') end) --every second Once

Section	Explanation
Configuration	Configuration for Wi-Fi connection.
Wi-Fi Mode	Sets the Wi-Fi mode to station mode.
Wi-Fi Event Handlers	Registers event handlers for Wi-Fi connection status: STA_CONNECTED, STA_DISCONNECTED, and STA_GOT_IP. These handlers print relevant information when these events occur.
TCP Connection	Creates a TCP connection to communicate with Google’s server.
Connection Handler	Event handler for connection. Upon establishing a connection, sends an HTTP request to Google’s server.
Data Receive Handler	Event handler for receiving data. When receiving a response from Google’s server, it prints the retrieved time.
Timer	Sets a timer to attempt reconnection to Google’s server every 10 seconds.

Result

> dofile("AEW_GoogleTime.lua")
> 
 STA - CONNECTED
 SSID: ArunEworld
 BSSID: c0:d0:70:c9:8d:a1
 Channel: 7

 STA - GOT IP
 Station IP: 192.168.1.103
 Subnet mask: 255.255.255.0
 Gateway IP: 192.168.1.1

Retrieved in 7881.115 milliseconds.
Google says it is Thu, 27 Apr 2017 15:05:55 GMT

Retrieved in 10166.297 milliseconds.
Google says it is Thu, 27 Apr 2017 15:05:58 GMT

Retrieved in 20194.126 milliseconds.
Google says it is Thu, 27 Apr 2017 15:06:08 GMT

--like every 10 seconds Once, will get time from Google--

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