ESP8266 AT Commands Notes (Version 1.4 with SDK 2.1.0)

AT
Should return OK

AT+GMR

Return the version information for the board

AT+CIFSR

Return IP info

Single Connection TCP 

//Set single connection mode

AT+CIPMUX=0

//Connect to test server

AT+CIPSTART="TCP","test.mosquitto.org",1883

//Check status

AT+CIPSTATUS

//Should return the following:

STATUS:3 //3 is for connected

+CIPSTATUS:0,"TCP","37.187.106.16",1883,10913,0

//Close the connection

AT+CIPCLOSE

Multiple Connection TCP

//Set multiple connection mode

AT+CIPMUX=1

//Connect to the first test server

AT+CIPSTART=0,"TCP","test.mosquitto.org",1883

//Connect to the second test server

AT+CIPSTART=1,"TCP","test.mosquitto.org",8883

//Check status

AT+CIPSTATUS

//Should return the following:

STATUS:3

+CIPSTATUS:0,"TCP","37.187.106.16",1883,44614,0

+CIPSTATUS:1,"TCP","37.187.106.16",8883,44244,0

//Close the connections

AT+CIPCLOSE=0

AT+CIPCLOSE=1

Send/Recieve Data

//Send data using

AT+CIPSEND=100 // 100 is the number of bytes to send.

<Data to send>

//Data from ESP8266

wait for +IPD,100://100 is the number of bytes being sent

//next characters are the data