ESP32 SHT30 Temperature and Humidity Sensor

Code Examples

Below you can find code examples of SHT30 Temperature and Humidity Sensor with ESP32 in several frameworks:

• Arduino IDE
• ESP-IDF
• ESPHome
• PlatformIO
• MicroPython

ESP32 SHT30 Arduino IDE Code Example

Example in Arduino IDE

Fill in your main Arduino IDE sketch file with the following code to use the SHT30 Temperature and Humidity Sensor:

#include <Wire.h>
#include "Adafruit_SHT31.h"

Adafruit_SHT31 sht31 = Adafruit_SHT31();

void setup() {
  Serial.begin(115200);
  while (!Serial) delay(10);

  if (!sht31.begin(0x44)) {   // Set to 0x45 for alternate i2c addr
    Serial.println("Couldn't find SHT31");
    while (1) delay(1);
  }
}

void loop() {
  float t = sht31.readTemperature();
  float h = sht31.readHumidity();

  if (!isnan(t) && !isnan(h)) {  // check if 'is not a number'
    Serial.print("Temp *C = "); Serial.print(t); Serial.print("	");
    Serial.print("Hum. % = "); Serial.println(h);
  } else {
    Serial.println("Failed to read from SHT31 sensor");
  }

  delay(1000);
}

This Arduino sketch demonstrates how to interface with the SHT30 sensor using the Adafruit SHT31 library. It initializes the sensor and reads temperature and humidity data every second, printing the results to the Serial Monitor. The sensor's I2C address is set to 0x44 by default; if your sensor uses the alternate address (0x45), adjust the initialization accordingly.

Connect your ESP32 to your computer via a USB cable, Ensure the correct Board and Port are selected under Tools, Click the "Upload" button in the Arduino IDE to compile and upload the code to your ESP32.

ESP32 SHT30 ESP-IDF Code Example

Example in Espressif IoT Framework (ESP-IDF)

If you're using ESP-IDF to work with the SHT30 Temperature and Humidity Sensor, here's how you can set it up and read data from the sensor. Fill in this code in the main ESP-IDF file:

#include <stdio.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "driver/i2c.h"

#define I2C_MASTER_SCL_IO    22    /*!< GPIO number used for I2C master clock */
#define I2C_MASTER_SDA_IO    21    /*!< GPIO number used for I2C master data */
#define I2C_MASTER_NUM       I2C_NUM_0 /*!< I2C master I2C port number */
#define I2C_MASTER_FREQ_HZ   100000     /*!< I2C master clock frequency */
#define SHT30_SENSOR_ADDR    0x44       /*!< SHT30 I2C address */

static esp_err_t i2c_master_init(void) {
    i2c_config_t conf = {
        .mode = I2C_MODE_MASTER,
        .sda_io_num = I2C_MASTER_SDA_IO,
        .scl_io_num = I2C_MASTER_SCL_IO,
        .sda_pullup_en = GPIO_PULLUP_ENABLE,
        .scl_pullup_en = GPIO_PULLUP_ENABLE,
        .master.clk_speed = I2C_MASTER_FREQ_HZ,
    };
    esp_err_t err = i2c_param_config(I2C_MASTER_NUM, &conf);
    if (err != ESP_OK) {
        return err;
    }
    return i2c_driver_install(I2C_MASTER_NUM, conf.mode, 0, 0, 0);
}

void read_sht30_sensor() {
    uint8_t data[6];
    i2c_master_write_read_device(I2C_MASTER_NUM, SHT30_SENSOR_ADDR, NULL, 0, data, sizeof(data), pdMS_TO_TICKS(1000));

    uint16_t temp_raw = (data[0] << 8) | data[1];
    uint16_t hum_raw = (data[3] << 8) | data[4];

    float temperature = -45 + 175 * ((float)temp_raw / 65535.0);
    float humidity = 100 * ((float)hum_raw / 65535.0);

    printf("Temperature: %.2f °C, Humidity: %.2f %%\n", temperature, humidity);
}

void app_main() {
    ESP_ERROR_CHECK(i2c_master_init());

    while (1) {
        read_sht30_sensor();
        vTaskDelay(pdMS_TO_TICKS(2000));
    }
}

This ESP-IDF code demonstrates how to interface with the SHT30 sensor using the I2C interface. It initializes the I2C master on GPIO21 (SDA) and GPIO22 (SCL) and reads temperature and humidity data from the SHT30. The sensor's raw data is processed and converted into human-readable temperature and humidity values. The readings are printed to the console every 2 seconds.

Update the I2C pins (I2C_MASTER_SDA_IO and I2C_MASTER_SCL_IO) to match your ESP32 hardware setup, Use idf.py build to compile the project, Use idf.py flash to upload the code to your ESP32.

ESP32 SHT30 ESPHome Code Example

Example in ESPHome (Home Assistant)

Fill in this configuration in your ESPHome YAML configuration file (example.yml) to integrate the SHT30 Temperature and Humidity Sensor

i2c:
  sda: GPIO21
  scl: GPIO22
  scan: true

sensor:
  - platform: sht3x
    address: 0x44
    temperature:
      name: "Room Temperature"
    humidity:
      name: "Room Humidity"
    update_interval: 60s

The ESPHome configuration uses the `sht3x` platform for interfacing with the SHT30 sensor. The `i2c` section specifies the SDA (GPIO21) and SCL (GPIO22) pins, enabling communication with the sensor. The `address` key indicates the I2C address of the SHT30 sensor (default `0x44`). Two sensor entities are defined: one for temperature and one for humidity, with user-friendly names such as 'Room Temperature' and 'Room Humidity.' The readings are updated every 60 seconds.

Upload this code to your ESP32 using the ESPHome dashboard or the esphome run command.

ESP32 SHT30 PlatformIO Code Example

Example in PlatformIO Framework

For PlatformIO, make sure to configure the platformio.ini file with the appropriate environment and libraries, and then proceed with the code.

Configure platformio.ini

First, your platformio.ini should look like below. You might need to include some libraries as shown. Make sure to change the board to your ESP32:

[env:esp32dev]
platform = espressif32
board = esp32dev
framework = arduino
lib_deps =
    adafruit/Adafruit SHT31 Library @ ^1.1.0
monitor_speed = 115200

ESP32 SHT30 PlatformIO Example Code

Write this code in your PlatformIO project under the src/main.cpp file to use the SHT30 Temperature and Humidity Sensor:

#include <Wire.h>
#include "Adafruit_SHT31.h"

Adafruit_SHT31 sht31 = Adafruit_SHT31();

void setup() {
    Serial.begin(115200);
    if (!sht31.begin(0x44)) {
        Serial.println("Couldn't find SHT30 sensor. Check wiring!");
        while (1);
    }
    Serial.println("SHT30 initialized.");
}

void loop() {
    float temperature = sht31.readTemperature();
    float humidity = sht31.readHumidity();

    if (!isnan(temperature) && !isnan(humidity)) {
        Serial.print("Temperature: ");
        Serial.print(temperature);
        Serial.println(" °C");

        Serial.print("Humidity: ");
        Serial.print(humidity);
        Serial.println(" %");
    } else {
        Serial.println("Failed to read from SHT30 sensor!");
    }
    delay(2000);
}

This PlatformIO code initializes the SHT30 sensor using the Adafruit library. The setup checks for the sensor's presence at the default I2C address `0x44`. If successful, the loop continuously reads temperature and humidity values, printing them to the Serial Monitor every 2 seconds. Any errors in reading are reported in the console.

Upload the code to your ESP32 using the PlatformIO "Upload" button in your IDE or the pio run --target upload command.

ESP32 SHT30 MicroPython Code Example

Example in Micro Python Framework

Fill in this script in your MicroPython main.py file (main.py) to integrate the SHT30 Temperature and Humidity Sensor with your ESP32.

from machine import Pin, I2C
from time import sleep
import sht31

# Initialize I2C (SDA=21, SCL=22)
i2c = I2C(0, scl=Pin(22), sda=Pin(21))
sensor = sht31.SHT31(i2c)

print("SHT30 Sensor Example")

while True:
    temperature, humidity = sensor.measure()
    print("Temperature: {:.2f} °C".format(temperature))
    print("Humidity: {:.2f} %".format(humidity))
    sleep(2)

This MicroPython code uses the `sht31` library to interface with the SHT30 sensor. The I2C bus is initialized on GPIO21 (SDA) and GPIO22 (SCL). The `sensor.measure()` function retrieves temperature and humidity readings, which are formatted and printed to the console every 2 seconds. The code is lightweight and ideal for microcontroller projects.

Upload this code to your ESP32 using a MicroPython-compatible IDE, such as Thonny, uPyCraft, or tools like ampy.