Before reading:

I write it on my PC typora ,but the passage may go wrong when I copy the passage to Utopian post editor.So I upload to the Github. If the article layout make you dazzled please read on the below url.Thanks.

The more readable version

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1.Necessary hardware

• ESP8266 -01 module

  
  

• USB -TTL transfer tool

  

• 3.3V power

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2.Necessary software

• Network debug assistant "Netassist.com"

  

• Serial port debug tool "sscom42.com"

  

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3.Connection

• ESP8266 PIN instrution

• Connect ESP8266 to USB-TLL tool

  ESP8266-01	USB-TTL tool
  UTXD	RX
  URXD	TX
  3.3V	3.3V
  CH_PD	3.3V
  GND	GND

• Computer properties setting

  Right click "My computer" then click "properties" ,choose "hardware" tab ,and find " Device manager",select "COM and LPT" and you will see the number of USB-To-Serial Comm Port. Remember it!(Like the picture below,My port is COM6)

• Debug

  • run the serial port debug tool "sscom42.com".Set the rate(波特率) as 115200 (New version of ESP8266 may be selected as 9600 )as well as the port as COM6.And remember click to select "send new line"(发送新行).Do as the picture marked below.

    

  • Then click "OPEN the buffer"(打开串口),and you will see some messy code,which is about the company information.You also can ignore it by click "Clearing"(清除).

    

  • Send AT commands to debug the ESP8266

    Frequently-used AT commands are listed below

    AT command	Explain
    AT+RST	restart module
    AT+CWMODE=3	set the mode
    AT+CWJAP="SSID Name","Password"	connect to the WIFI SSID
    AT+CIFSR	check up IP
    AT+CIPSTART="TCP","192.168.1.100",8080	connect to TCP server
    AT+CIPSEND=4	set the length of message

    AT command :

    ​ restart the module.

    AT+RST

    Receive :

    OK
    
    ets Jan  8 2013,rst cause:4, boot mode3,6)
    
    wdt reset
    load 0x40100000, len 816, room 16
    tail 0
    chksum 0x8d
    load 0x3ffe8000, len 788, room 8
    tail 12
    chksum 0xcf
    ho 0 tail 12 room 4
    load 0x3ffe8314, len 288, room 12
    tail 4
    chksum 0xcf
    csum 0xcf
    
    2nd boot version : 1.2
      SPI Speed      : 40MHz
      SPI Mode       : QIO
      SPI Flash Size : 4Mbit
    jump to run user1
    
    Ai-ThinkerTechnology Co. Ltd.
    
    Invalid
    

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    AT command:

    ​ set the mode of ESP8266 as "softAP + station",which can let ESP8266 generate the AP and at the same time connect to WIFI Station.

    ​ The picture below shows the AP which ESP8266 has generated.

    ​

    AT+CWMODE=3

  ​ Receive:

  AT+CWMODE=3
  OK
  

  ---

  ​ AT command:

  ​ While ESP8266 is on "Station" mode,you can send the AT command below to connect to the existing WIFI .(My wifi name is 'Laoli',and the password is 'lrh13888'. so I modify the AT command as below)

  AT+CWJAP="Laoli","lrh13888"

  ​ Receive:

  AT+CWJAP="Laoli","lrh13888"
  OK
  

  ​

  ---

  ​ AT command:

  ​ After conected to the WIFI , sending this AT command can get the IP.

  AT+CIFSR

  ​ Receive:

  AT+CIFSR
  +CIFSR:APIP,"192.168.4.1"
  +CIFSR:APMAC,"1a:fe:34:fa:b8:25"
  +CIFSR:STAIP,"192.168.1.107"
  +CIFSR:STAMAC,"18:fe:34:fa:b8:25"
  
  OK
  

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  ​ AT command:

  ​ Firtstly set up the TCP server by using network debug assistant "Netassist.com"

  ​

  After the TCP server successfully setting , sending this AT command can connect to the server.Remember to input the correct IP and port.

  AT+CIPSTART="TCP","192.168.1.100",8080

  ​ Receive:

  AT+CIPSTART="TCP","192.168.1.100",8080
  CONNECT
  OK
  

  ---

  ​ AT command:

  ​ Sending message to TCP server which we have connected to.

  ​ Firstly ,set the length of the following message.

  AT+CIPSEND=4

  ​ and we will receive:

  AT+CIPSEND=4
  OK
  > 
  

  ​ When we see the mark ">",it means we can send the message body .

  ​ Then I send "ABCD" four letters

  ​ Receive:

  ​

  ​

  ​ What we send will be seen in the monitor of "Netassist.com"

  【Receive from 192.168.1.107 :20618】：03 08 41 42 41 42 43 44 41 42 43 44
  

​

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4.Summary

Generally ,we use ESP8266 and Arduino for network communications with server or client.Just taking advantages of the AT commands I list above can easily meet the normal requirements.

But this is only the basics of network communications .More funny functions are waiting to be achieved.

**Next time I will share some of complex projects about the ESP8266 and Arduino **.

Please look forward to it

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Thanks for reading patiently.

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Posted on Utopian.io - Rewarding Open Source Contributors

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