ESP8266 have 512 bytes of internal EEPROM, it is useful when you want to store some settings, such as IP address of server, WEP key, SSID of WiFi.
In this lesson we will see writing data to EEPOM and reading from EEPROM
To write byte to EEPROM we need two commands Continue reading Internal EEPROM ESP8266
Software serial uses timer, be careful when you are using software serial. Timer is also used for WiFi communication section if you don’t give enough time to WiFi routines it will create problem of stack error or misbehavior. It is better to use software serial only when you need two serial ports and also avoid use of software serial for data reception.