It is used only when you initialize serial i.e. This command is used to initialize serial port with 9600 baud rate. Click the Tools>Serial monitor button in the toolbar and select the same baud rate used in the call to begin().īefore we start our program lets understand commonly used serial commands Serial.begin(9600) You can use the Arduino IDE environment’s built-in serial monitor to communicate with an ESP board. All ESP boards have at least one serial port (also known as a UART or USART): Serial. Serial is used for communication between the Arduino board and a computer or other devices. Don’t connect these pins directly to an RS232 serial port they operate at +/- 12V and can damage your ESP8266 board. Serial communication on pins TX/RX uses TTL logic levels 3.3V. Logic Level ConversionĪssuming that you have already connected serial with your USB to Serial converter or You are using ESP Witty, Node MCU. Hardware Serial Communicationįor Level conversion from 3.3V to 5V we need only two components.

Serial interface is useful for debugging the programs by sending some debug info to serial. It is better to keep baud rate below 115200. Remember that few USB to Serial converter does not support higher baud rate. Hardware Serial Programming is similar to the Arduino Serial. On ESP8266 we have one hardware serial i.e. We are discussing on how to do 3.3V to 5V level conversion for converting serial TTL to RS232 level from 3.3V you can use MAX3232 it operates at 3.3V levels. Serial interface is common requirement for most of the application development.

Software serial esp8266 tutorial