One is from Espressif, the manufacturer of the ESP8266 chip, the other is from AI-Thinker, the manufacturer of the ESP8266 modules. Also there are two different types of the AT firmware. I believe the AT commands were different with older versions of the AT firmware (at one point it was AT_UART). You can get information on the AT firmware by running AT+GMR but of course that means you need to be able to successfully do serial communication with the ESP8266. You'll notice that the commands are AT+UART_CUR to temporarily configure the UART settings (will be lost after power down) or AT+UART_DEF to permanently configure the UART settings (written to non-volatile flash memory). If you look at the documentation for the recent versions of the Espressif AT firmware: 4a-esp8266_at_instruction_set_en.pdf The trouble with the above is that SoftwareSerial doesn't reliably work at 115200 so you have no assurance that the AT+CIOBAUD command will not be garbled and thus fail to configure the ESP8266 to 9600 baud.ДЄlso, note that AT+CIOBAUD is not a valid command on some versions of the AT firmware. SendData('AT+CIOBAUD=9600 ', 2000, DEBUG) // configure the ESP8266 to communicate at 9600 baudД®sp8266.begin(9600) // now that the ESP8266 has been configured to communicate at 9600 baud we need to switch to that baud rate You could try this: esp8266.begin(115200) // start at 115200 baud because that is the default configuration of the ESP8266 AT firmware. If it's running at 115200 this won't work because when you send the AT command at 9600 it just comes through to the ESP8266 as garbage so it will never recognize the AT+CIOBAUD command. String sendData(String command, const int timeout, boolean debug)

String command = msg.substring(0, 3) //first 3 characters = command Msg = esp8266.readStringUntil(' ') //read whole message

If (esp8266.find('+IPD,')) //if there is a messageД®sp8266.find('?') //look for the message If (esp8266.available()) //verify incoming data Hello I am doing a project I saw on instructables and I canвЂ™t do it, I am using an esp 8266 8-pin wifi card which is connected to the pins 2 and 3 (who partnered to serial port) but i donвЂ™t receive any data i asked in the code, already checked the connections in the serial,the wifi card, and the COM ports.

Esp8266 serial port com weird