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Hello again @felmue,

I came across this Adafruit video today, and I thought maybe you'd be interested?

https://youtu.be/m0XAT8V37-g?t=412

(The interesting part is between 6'52" and 13'05")

=> Power Profiler Kit II

Cheers
Steph

Well... I'm soooooo sorry... I thought I had an ENV III, but it's actually an ENV II... 😬

ENV II even has two temperature sensors, since instead of the QMP6988, it has a BMP280, which is a pressure and temperature sensor. It is, therefore, possible to perform 2 simultaneous temperature measurements!

So, this time things work better:

We still notice a difference in the temperature measurements. The SHT30 seems to get better results (which is probably why they added it).

Here, it's still 1°C above the real temperature. In the meantime, I turned on the air-conditioning, so maybe the deviation is reduced because of the ventilation? On the other hand, we can see that the temperature measured by the BMP280 is 1°C higher than the one measured by the SHT30.

But this time, I get a non-zero pressure measurement. 🙂

Here is the new version of my code for those who are interested:

#include <M5Unified.h>
#include <UNIT_ENV.h>
#include <Adafruit_BMP280.h>

constexpr uint32_t SLEEP_DURATION_US = 30 * 1000 * 1000; // 30 sec

SHT3X sht30;
Adafruit_BMP280 bmp;
// QMP6988 qmp6988; // only for ENV III

void setup() {

    M5.begin();
    M5.Display.setRotation(3);
    M5.Display.setFont(&fonts::Font2);

    Wire.begin(0, 26);
    bmp.begin(0x76);
    bmp.setSampling(
        Adafruit_BMP280::MODE_NORMAL,
        Adafruit_BMP280::SAMPLING_X16,
        Adafruit_BMP280::SAMPLING_X16,
        Adafruit_BMP280::FILTER_X16,
        Adafruit_BMP280::STANDBY_MS_500
    );

    // qmp6988.init(); // only for ENV III
    
}

void displayMeasurement(
    const uint8_t x1,
    const uint8_t x2,
    const uint8_t x3,
    const uint8_t y,
    const char*   sensor,
    const char*   data,
    const float_t value
) {

    M5.Display.drawString(sensor,  x1, y);
    M5.Display.drawString(data,    x2, y);
    M5.Display.drawFloat(value, 2, x3, y);

}

void loop() {

    static float_t temperature_1, temperature_2, humidity, pressure;

    uint8_t fail = sht30.get();

    temperature_1 = bmp.readTemperature();
    temperature_2 = fail ? 0 : sht30.cTemp;
    humidity      = fail ? 0 : sht30.humidity;
    pressure      = bmp.readPressure();
    
    // only for ENV III
    // pressure = qmp6988.calcPressure();
    // qmp6988.setpPowermode(QMP6988_SLEEP_MODE);

    displayMeasurement(10, 70, 100, 10, "BMP280", "T1", temperature_1);
    displayMeasurement(10, 70, 100, 30, "SHT30",  "T2", temperature_2);
    displayMeasurement(10, 70, 100, 50, "SHT30",  "H",  humidity);
    displayMeasurement(10, 70, 100, 70, "BMP280", "P",  pressure);

    delay(2000);
    
    M5.Power.deepSleep(SLEEP_DURATION_US);

}

Sorry for my confusion between ENV II and ENV III. But maybe finally the questions raised here will be useful to some readers...