#include <Arduino.h>

#define DO_PIN A1

void setup()
{
  Serial.begin(115200);
}

void loop()
{

  int analogValue = analogRead(A0);
  const float BETA = 3950;  // should match the Beta Coefficient of the thermistor
  float  temperature =  1 / (log(1 / (1023. / analogValue - 1)) / BETA + 1.0 / 298.15) - 273.15;

  float voltage = analogRead(DO_PIN) / 1023.0 * 5000;   // read the voltage
  float DOvalue =  readDO(voltage, temperature);

  Serial.print("Temperaturet:\t" + String(temperature) + "\t");
  Serial.print("DO:\t" + String(DOvalue) + "\t");
  Serial.print("Voltage_mv:\t" + String(voltage));
  Serial.println();

  delay(1000);
}



float readDO(float voltage_mv, float temperature_c) {

  if (temperature_c < 0.0 | temperature_c > 40.0) return 0.0;

  //Single-point calibration Mode=0
  //Two-point calibration Mode=1
#define TWO_POINT_CALIBRATION 1

  //Single point calibration needs to be filled CAL1_V and CAL1_T
#define CAL1_V (1600) //mv
#define CAL1_T (25)   //℃
  //Two-point calibration needs to be filled CAL2_V and CAL2_T
  //CAL1 High temperature point, CAL2 Low temperature point
#define CAL2_V (1300) //mv
#define CAL2_T (15)   //℃

  const uint16_t DO_Table[41] = {
    14460, 14220, 13820, 13440, 13090, 12740, 12420, 12110, 11810, 11530,
    11260, 11010, 10770, 10530, 10300, 10080, 9860, 9660, 9460, 9270,
    9080, 8900, 8730, 8570, 8410, 8250, 8110, 7960, 7820, 7690,
    7560, 7430, 7300, 7180, 7070, 6950, 6840, 6730, 6630, 6530, 6410
  };

#if TWO_POINT_CALIBRATION == 0
  // uint16_t V_saturation = (uint32_t)CAL1_V + (uint32_t)35 * temperature_c - (uint32_t)CAL1_T * 35;
  //return (voltage_mv * DO_Table[temperature_c] / V_saturation);

  float V_saturation = CAL1_V + 35 * (uint8_t)temperature_c - CAL1_T * 35;
  return (voltage_mv * DO_Table[(uint8_t)temperature_c] / V_saturation);
#else
  //uint16_t V_saturation = (int16_t)((int8_t)temperature_c - CAL2_T) * ((uint16_t)CAL1_V - CAL2_V) / ((uint8_t)CAL1_T - CAL2_T) + CAL2_V;
  //return (voltage_mv * DO_Table[temperature_c] / V_saturation);

  float V_saturation = ((uint8_t)temperature_c - CAL2_T) * (CAL1_V - CAL2_V) / (CAL1_T - CAL2_T) + CAL2_V;
  return (voltage_mv * DO_Table[(uint8_t)temperature_c] / V_saturation);
#endif
}