ESP-32s Project with Arduino and PlatformIO

This project consists of an ESP-32s that uses Arduino libraries to receive data (temperature, air/soil humidity, and light intensity) through UART and send it to an MQTT server on Ubidots. PlatformIO is used as the integrated development environment (IDE).

Before start

Before compiling the project, you must create a file named wifi_credentials.h with the following defined macros:

#define WIFI_SSID_SECRETS "<Network Name>"
#define WIFI_PASSWORD_SECRETS "<Password>"
#define UBIDOTS_TOKEN_SECRETS "<Ubidots Token>"
#define DEVICE_LABEL_SECRETS "<Device name>"

| ⚠️ Make sure to replace the example values with your own data before compiling.

Customization

Additionally, you can customize the project by overwriting the following constants:

#define DATA_UART <UART NUMBER>
#define SERIAL_RX <PIN TO RECEIVE DATA>
#define SERIAL_TX <PIN TO TRANSMIT DATA>
#define BAUD_RATE <BAUD RATE TO TRANSMIT DATA>
#define FREQUENCY_TO_PUBLISH_IN_M <FREQUENCY TO PUBLISH IN MINUTES>
#define FREQUENCY_TO_PUBLISH_IN_MS (FREQUENCY_TO_PUBLISH_IN_M * 60 * 1000)

| ⚠️ Make sure that the slave device transmits at the same baud rate defined in the BAUD_RATE macro.

Future changes

We are planning to add the following features in the future:

• Add support for sensors without dependency on an external MCU.
• Receive signals from the MQTT server to control some actuators.
• Set the device to sleep mode to save energy.
• Set the WiFi credentials through the next options:
  • Through the MQTT server.
  • Through a web app.
  • Through a mobile app.
  • Through a Bluetooth connection.

Libraries

The following libraries are used in this project:

• Ubidots Arduino MQTT
• HardwareSerial
• Arduino

References

• Connect an ESP32-DevKitC to Ubidots over MQTT
• ESP32 UART Communication Explained with Example