Tasmota/tasmota/xsns_78_ezohum.ino

/*
  xsns_78_ezohum.ino - EZO HUM I2C HUM sensor support for Tasmota

  Copyright (C) 2020  Christopher Tremblay

  This program is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifdef USE_I2C
#ifdef USE_EZOHUM

#define EZO_HUM_READ_LATENCY   300

struct EZOHUM : public EZOStruct {
  EZOHUM(uint32_t addr) : EZOStruct(addr), humidity(NAN), temperature(NAN) {}

  virtual void ProcessMeasurement(void)
  {
    char data[D_EZO_MAX_BUF];
    // Hum, Temp, Dew

    EZOStruct::ProcessMeasurement(data, sizeof(data), EZO_HUM_READ_LATENCY);

    humidity = CharToFloat(data);

    char *next = strchr(data, ',');
    if (next) {
      temperature = CharToFloat(next + 1);
    }
  }

  virtual void Show(bool json, const char *name)
  {
    if (isnan(temperature)) {
      char parameter[FLOATSZ];

      dtostrfd(humidity, Settings.flag2.humidity_resolution, parameter);
      WSContentSend_PD(HTTP_SNS_HUM, name, parameter);
    } else {
      TempHumDewShow(json, (0 == TasmotaGlobal.tele_period), name, temperature, humidity);
    }
  }

  static const char id[] PROGMEM;

private:
  float     humidity;
  float     temperature;
};

const char EZOHUM::id[] PROGMEM = "HUM";

#endif  // USE_EZOHUM
#endif  // USE_I2C