Write the \"weather\" class needed in this c++ project. \"Sensors that can detec

Question

Write the "weather" class needed in this c++ project.

"Sensors that can detect humidity and temperature will be able to analyze and differentiate various weather conditions. A light sensor will determine the setting for the LED accordingly. The data picked up from these sensors will be stored and sent to the location (i.e. city)."

Streetlight Controller GPS getweathero: double getLighto: double + getTraffico, double getStreetLight0: double setcommunication0: void Light Weather Commu getLighto: double Humidity Temperature Sensors

Explanation / Answer

Save the below code as DTH.cpp.

Download "DHT.h". Save to your directory

Make sure that the DHT.h file is available to the DTH.cpp

DTH.cpp:

#include "DHT.h"

#define MIN_INTERVAL 2000

DHT::DHT(uint8_t pin, uint8_t type, uint8_t count) {
_pin = pin;
_type = type;
#ifdef __AVR
_bit = digitalPinToBitMask(pin);
_port = digitalPinToPort(pin);
#endif
_maxcycles = microsecondsToClockCycles(1000);
}

void DHT::begin(void) {

pinMode(_pin, INPUT_PULLUP);
_lastreadtime = -MIN_INTERVAL;
DEBUG_PRINT("Max clock cycles: "); DEBUG_PRINTLN(_maxcycles, DEC);
}

float DHT::readTemperature(bool S, bool force) {
float f = NAN;

if (read(force)) {
switch (_type) {
case DHT11:
f = data[2];
if(S) {
f = convertCtoF(f);
}
break;
case DHT22:
case DHT21:
f = data[2] & 0x7F;
f *= 256;
f += data[3];
f *= 0.1;
if (data[2] & 0x80) {
f *= -1;
}
if(S) {
f = convertCtoF(f);
}
break;
}
}
return f;
}

float DHT::convertCtoF(float c) {
return c * 1.8 + 32;
}

float DHT::convertFtoC(float f) {
return (f - 32) * 0.55555;
}

float DHT::readHumidity(bool force) {
float f = NAN;
if (read()) {
switch (_type) {
case DHT11:
f = data[0];
break;
case DHT22:
case DHT21:
f = data[0];
f *= 256;
f += data[1];
f *= 0.1;
break;
}
}
return f;
}

float DHT::computeHeatIndex(float temperature, float percentHumidity, bool isFahrenheit) {
float hi;

if (!isFahrenheit)
temperature = convertCtoF(temperature);

hi = 0.5 * (temperature + 61.0 + ((temperature - 68.0) * 1.2) + (percentHumidity * 0.094));

if (hi > 79) {
hi = -42.379 +
2.04901523 * temperature +
10.14333127 * percentHumidity +
-0.22475541 * temperature*percentHumidity +
-0.00683783 * pow(temperature, 2) +
-0.05481717 * pow(percentHumidity, 2) +
0.00122874 * pow(temperature, 2) * percentHumidity +
0.00085282 * temperature*pow(percentHumidity, 2) +
-0.00000199 * pow(temperature, 2) * pow(percentHumidity, 2);

if((percentHumidity < 13) && (temperature >= 80.0) && (temperature <= 112.0))
hi -= ((13.0 - percentHumidity) * 0.25) * sqrt((17.0 - abs(temperature - 95.0)) * 0.05882);

else if((percentHumidity > 85.0) && (temperature >= 80.0) && (temperature <= 87.0))
hi += ((percentHumidity - 85.0) * 0.1) * ((87.0 - temperature) * 0.2);
}

return isFahrenheit ? hi : convertFtoC(hi);
}

boolean DHT::read(bool force) {
uint32_t currenttime = millis();
if (!force && ((currenttime - _lastreadtime) < 2000)) {
return _lastresult; // return last correct measurement
}
_lastreadtime = currenttime;

data[0] = data[1] = data[2] = data[3] = data[4] = 0;

digitalWrite(_pin, HIGH);
delay(250);

pinMode(_pin, OUTPUT);
digitalWrite(_pin, LOW);
delay(20);

uint32_t cycles[80];
{ InterruptLock lock;
digitalWrite(_pin, HIGH);
delayMicroseconds(40);

pinMode(_pin, INPUT_PULLUP);
delayMicroseconds(10);
if (expectPulse(LOW) == 0) {
DEBUG_PRINTLN(F("Timeout waiting for start signal low pulse."));
_lastresult = false;
return _lastresult;
}
if (expectPulse(HIGH) == 0) {
DEBUG_PRINTLN(F("Timeout waiting for start signal high pulse."));
_lastresult = false;
return _lastresult;
}

for (int i=0; i<80; i+=2) {
cycles[i] = expectPulse(LOW);
cycles[i+1] = expectPulse(HIGH);
}
}
for (int i=0; i<40; ++i) {
uint32_t lowCycles = cycles[2*i];
uint32_t highCycles = cycles[2*i+1];
if ((lowCycles == 0) || (highCycles == 0)) {
DEBUG_PRINTLN(F("Timeout waiting for pulse."));
_lastresult = false;
return _lastresult;
}
data[i/8] <<= 1;
if (highCycles > lowCycles) {
data[i/8] |= 1;
}
}

DEBUG_PRINTLN(F("Received:"));
DEBUG_PRINT(data[0], HEX); DEBUG_PRINT(F(", "));
DEBUG_PRINT(data[1], HEX); DEBUG_PRINT(F(", "));
DEBUG_PRINT(data[2], HEX); DEBUG_PRINT(F(", "));
DEBUG_PRINT(data[3], HEX); DEBUG_PRINT(F(", "));
DEBUG_PRINT(data[4], HEX); DEBUG_PRINT(F(" =? "));
DEBUG_PRINTLN((data[0] + data[1] + data[2] + data[3]) & 0xFF, HEX);

if (data[4] == ((data[0] + data[1] + data[2] + data[3]) & 0xFF)) {
_lastresult = true;
return _lastresult;
}
else {
DEBUG_PRINTLN(F("Checksum failure!"));
_lastresult = false;
return _lastresult;
}
}

uint32_t DHT::expectPulse(bool level) {
uint32_t count = 0;
#ifdef __AVR
uint8_t portState = level ? _bit : 0;
while ((*portInputRegister(_port) & _bit) == portState) {
if (count++ >= _maxcycles) {
return 0; // Exceeded timeout, fail.
}
}
#else
while (digitalRead(_pin) == level) {
if (count++ >= _maxcycles) {
return 0; // Exceeded timeout, fail.
}
}
#endif

return count;
}

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