Output from DHT22

Mbed Studio
4

Hello,

usually is good to share also MbedOs version.

However, I tried that library with MbedOS 5.15.8 on Nucleo-F767ZI and output is OK

Temperature in Kelvin: 300.15, Celcius: 27.00, Farenheit 80.60
Humidity is 47.00, Dewpoint: 14.75, Dewpoint fast: 14.71

But you miss important part, you have to call readData() function. Without it you will read 0 every time because the rest of functions only calculate a conversion of measured data.

#include "mbed.h"
#include "DHT.h"
  
  DHT sensor(D4, DHT22);
  
  int main()
  {
      int error = 0;
      float h = 0.0f, c = 0.0f, f = 0.0f, k = 0.0f, dp = 0.0f, dpf = 0.0f;
 
      while(1) {
          thread_sleep_for(2000);
          error = sensor.readData();
          if (0 == error) {
              c   = sensor.ReadTemperature(CELCIUS);
              f   = sensor.ReadTemperature(FARENHEIT);
              k   = sensor.ReadTemperature(KELVIN);
              h   = sensor.ReadHumidity();
              dp  = sensor.CalcdewPoint(c, h);
              dpf = sensor.CalcdewPointFast(c, h);
              printf("Temperature in Kelvin: %4.2f, Celcius: %4.2f, Farenheit %4.2f\n", k, c, f);
              printf("Humidity is %4.2f, Dewpoint: %4.2f, Dewpoint fast: %4.2f\n", h, dp, dpf);
          } else {
              printf("Error: %d\n", error);
          }
      }
  }

For MbedOS6+ DHT - Fork of DHT component - https://os.mbed.com/teams… | Mbed also OK, but for that you also need to change printf lib in mbed_app.json

{
    "target_overrides": {
        "*": {
            "target.printf_lib": "std"
        }
    }
}

BR, Jan