Select Arduino Board and Arduino Port before uploading the code.
Arduino include serial library serial#
It will transfer sensor data to NodeMCU via serial communication.Ĭircuit for Sending data from Arduino to ESP8266 NodeMCU with Voltage Divider: We have connected DHT22 sensor on Arduino Uno. But you can reduce Arduino’s power supply voltage, so it can provide little low voltage than 5V or near to 3.5 V.ġ) Send Data from Arduino to ESP8266 NodeMCU:
In my case voltage divider didn’t work and we know Arduino provide 5V if it is connected to USB or 5V power supply. In addition to this I tried reducing baud rate but it also didn’t work. It was 3.3V that means voltage divider connection is correct. I tried everything to make it work, checked voltage with multimeter. when I connect direct Arduino’s Tx to NodeMCU’s Rx, it starts showing sensor data. It shows blank screen on serial monitor, if it is connected via voltage divider. By using voltage divider you are reducing Arduino Tx 5V to 3.3V for Rx of ESP8266. Voltage Divider for NodeMCU’s Serial Communication Rx Pin:ĮSP8266 works on 3.3V and Arduino Tx pin supplies 5V, which can damage your ESP8266 NodeMCU. Software Serial library: This library is inbuilt in Arduino IDE. So I need this library for that sensor to work. Īs in this project I am transferring DHT sensor data from Arduino to NodeMCU and NodeMCU to Arduino.
Arduino include serial library how to#
You can read How to setup ESP8266 for first time in Arduino IDE. Make sure you already setup ESP8266 for Arduino IDE.
If you are doing lots of things on both Arduino and ESP8266 NodeMCU. Apart from this we will also see how to use software serial library on Arduino and Serial1 on ESP8266 NodeMCU, So that you can transfer data with another serial port, which we will be helpful. Moreover, we will transfer DHT22 Sensor data from Arduino to NodeMCU and NodeMCU to Arduino. Serial communication is required when you want to transfer sensor data or any data from one device to another device, In our case it is ESP8266 NodeMCU and Arduino. In this tutorial we will learn how to make serial communication between Arduino to ESP8266 & ESP8266 to Arduino.