SHT41 / SHT41-D / GY-SHT41-D Temperature and Humidity Sensor

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

#define I2C_MASTER_SCL_IO    22    /*!< GPIO number for I2C master clock */
#define I2C_MASTER_SDA_IO    21    /*!< GPIO number for I2C master data */
#define I2C_MASTER_NUM       I2C_NUM_0 /*!< I2C master port */
#define I2C_MASTER_FREQ_HZ   100000     /*!< I2C master clock frequency */
#define SHT41_SENSOR_ADDR    0x44       /*!< SHT41 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_ERROR_CHECK(i2c_param_config(I2C_MASTER_NUM, &conf));
    return i2c_driver_install(I2C_MASTER_NUM, conf.mode, 0, 0, 0);
}

void read_sht41_sensor() {
    uint8_t data[6];
    uint8_t cmd[] = {0xFD}; // High precision measurement command
    i2c_master_write_to_device(I2C_MASTER_NUM, SHT41_SENSOR_ADDR, cmd, 1, pdMS_TO_TICKS(1000));
    vTaskDelay(pdMS_TO_TICKS(10));
    i2c_master_read_from_device(I2C_MASTER_NUM, SHT41_SENSOR_ADDR, data, 6, 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_sht41_sensor();
        vTaskDelay(pdMS_TO_TICKS(2000));
    }
}

i2c:
  sda: GPIO21
  scl: GPIO22

sensor:
  - platform: sht4x
    address: 0x44
    temperature:
      name: "Room Temperature"
    humidity:
      name: "Room Humidity"
    update_interval: 60s

[env:esp32dev]
platform = espressif32
board = esp32dev
framework = arduino
monitor_speed = 115200
lib_deps =
    adafruit/Adafruit SHT4x Library @ ^1.0.5

#include <Arduino.h>
#include <Wire.h>
#include "Adafruit_SHT4x.h"

Adafruit_SHT4x sht4;

void setup() {
  Serial.begin(115200);
  if (!sht4.begin()) {
    Serial.println("Couldn't find SHT41 sensor!");
    while (1) delay(10);
  }
  sht4.setPrecision(SHT4X_HIGH_PRECISION);
  Serial.println("SHT41 initialized");
}

void loop() {
  sensors_event_t humidity, temp;
  if (!sht4.getEvent(&humidity, &temp)) {
    Serial.println("Failed to read sensor data");
    return;
  }
  Serial.print("Temperature: "); Serial.print(temp.temperature); Serial.println(" °C");
  Serial.print("Humidity: "); Serial.print(humidity.relative_humidity); Serial.println(" %");
  delay(2000);
}

from machine import I2C, Pin
from time import sleep

# Initialize I2C interface
i2c = I2C(0, scl=Pin(22), sda=Pin(21))

# SHT41 I2C address
SHT41_ADDR = 0x44

# Command for high-precision measurement
MEASURE_CMD = b'\xFD'

while True:
    try:
        i2c.writeto(SHT41_ADDR, MEASURE_CMD)
        sleep(0.01)  # Wait for measurement to complete
        data = i2c.readfrom(SHT41_ADDR, 6)
        raw_temp = (data[0] << 8) | data[1]
        raw_hum = (data[3] << 8) | data[4]
        temperature = -45 + 175 * (raw_temp / 65535.0)
        humidity = 100 * (raw_hum / 65535.0)
        print("Temperature: {:.2f} °C".format(temperature))
        print("Humidity: {:.2f} %".format(humidity))
    except Exception as e:
        print("Error reading SHT41: ", e)
    sleep(2)