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Converted to C++ and esp-idf

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feedc0de
2021-07-13 16:25:32 +02:00
parent f339feb6b6
commit 57ebd8cbd3
5 changed files with 188 additions and 127 deletions
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DHT.cpp
+67 -53
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@@ -66,7 +66,7 @@ void DHT::begin(uint8_t usec) {
// Using this value makes sure that millis() - lastreadtime will be
// >= MIN_INTERVAL right away. Note that this assignment wraps around,
// but so will the subtraction.
_lastreadtime = millis() - MIN_INTERVAL;
_lastreadtime = espchrono::millis_clock::now() - std::chrono::milliseconds{MIN_INTERVAL};
DEBUG_PRINT("DHT max clock cycles: ");
DEBUG_PRINTLN(_maxcycles, DEC);
pullTime = usec;
@@ -82,44 +82,48 @@ void DHT::begin(uint8_t usec) {
* true if in force mode
* @return Temperature value in selected scale
*/
float DHT::readTemperature(bool S, bool force) {
std::optional<float> DHT::readTemperature(bool S, bool force) {
if (!read(force))
return std::nullopt;
float f = NAN;
if (read(force)) {
switch (_type) {
case DHT11:
f = data[2];
if (data[3] & 0x80) {
f = -1 - f;
}
f += (data[3] & 0x0f) * 0.1;
if (S) {
f = convertCtoF(f);
}
break;
case DHT12:
f = data[2];
f += (data[3] & 0x0f) * 0.1;
if (data[2] & 0x80) {
f *= -1;
}
if (S) {
f = convertCtoF(f);
}
break;
case DHT22:
case DHT21:
f = ((word)(data[2] & 0x7F)) << 8 | data[3];
f *= 0.1;
if (data[2] & 0x80) {
f *= -1;
}
if (S) {
f = convertCtoF(f);
}
break;
switch (_type) {
case DHT11:
f = data[2];
if (data[3] & 0x80) {
f = -1 - f;
}
f += (data[3] & 0x0f) * 0.1;
if (S) {
f = convertCtoF(f);
}
break;
case DHT12:
f = data[2];
f += (data[3] & 0x0f) * 0.1;
if (data[2] & 0x80) {
f *= -1;
}
if (S) {
f = convertCtoF(f);
}
break;
case DHT22:
case DHT21:
f = ((word)(data[2] & 0x7F)) << 8 | data[3];
f *= 0.1;
if (data[2] & 0x80) {
f *= -1;
}
if (S) {
f = convertCtoF(f);
}
break;
default:
return std::nullopt;
}
return f;
}
@@ -145,20 +149,23 @@ float DHT::convertFtoC(float f) { return (f - 32) * 0.55555; }
* force read mode
* @return float value - humidity in percent
*/
float DHT::readHumidity(bool force) {
std::optional<float> DHT::readHumidity(bool force) {
if (!read(force))
return std::nullopt;
float f = NAN;
if (read(force)) {
switch (_type) {
case DHT11:
case DHT12:
f = data[0] + data[1] * 0.1;
break;
case DHT22:
case DHT21:
f = ((word)data[0]) << 8 | data[1];
f *= 0.1;
break;
}
switch (_type) {
case DHT11:
case DHT12:
f = data[0] + data[1] * 0.1;
break;
case DHT22:
case DHT21:
f = ((word)data[0]) << 8 | data[1];
f *= 0.1;
break;
default:
return std::nullopt;
}
return f;
}
@@ -171,9 +178,16 @@ float DHT::readHumidity(bool force) {
*(default true)
* @return float heat index
*/
float DHT::computeHeatIndex(bool isFahrenheit) {
float hi = computeHeatIndex(readTemperature(isFahrenheit), readHumidity(),
isFahrenheit);
std::optional<float> DHT::computeHeatIndex(bool isFahrenheit) {
const auto temperature = readTemperature(isFahrenheit);
if (!temperature)
return std::nullopt;
const auto humidity = readHumidity();
if (!humidity)
return std::nullopt;
float hi = computeHeatIndex(*temperature, *humidity, isFahrenheit);
return hi;
}
@@ -231,8 +245,8 @@ float DHT::computeHeatIndex(float temperature, float percentHumidity,
bool DHT::read(bool force) {
// Check if sensor was read less than two seconds ago and return early
// to use last reading.
uint32_t currenttime = millis();
if (!force && ((currenttime - _lastreadtime) < MIN_INTERVAL)) {
espchrono::millis_clock::time_point currenttime = espchrono::millis_clock::now();
if (!force && ((currenttime - _lastreadtime) < std::chrono::milliseconds{MIN_INTERVAL})) {
return _lastresult; // return last correct measurement
}
_lastreadtime = currenttime;