Replaces previous code with premade DHT library code for mbed, change…

…s to allow it to work with sensor module

libs/sensors/include/DHT22.h

@@ -1,32 +1,82 @@
-#pragma once
-
-#include "Sensor.h"
-#include "mbed.h"
-
-namespace Sensor {
-class DHT22 final : public Sensor {
- public:
-  DHT22(PinName data);
-
-  // Returns internal humidity value (and temperature? Since all transmitted at the same time...)
-  float read() override;
-
-  // Returns internal temperature reading *Probably irrelevant?
-  float alternateRead() override;
-
-  // Returns whether sensor responds to request?
-  bool getStatus() const override;
-
-  // irrelevant probably
-  [[nodiscard]] bool reset() override;
-
-  // Requests relative humidity and temperature data from sensor
-  [[nodiscard]] bool update() override;
-
- private:
-  mutable DigitalInOut m_data;
-  bool updateData();
-
-  float m_humidity, m_temperature;
-};
-}  // namespace Sensor
+/*
+ *  DHT Library for  Digital-output Humidity and Temperature sensors
+ *
+ *  Works with DHT11, DHT21, DHT22
+ *             SEN11301P,  Grove - Temperature&Humidity Sensor     (Seeed Studio)
+ *             SEN51035P,  Grove - Temperature&Humidity Sensor Pro (Seeed Studio)
+ *             AM2302   ,  temperature-humidity sensor
+ *             RHT01,RHT02, RHT03    ,  Humidity and Temperature Sensor         (Sparkfun)
+ *
+ *  Copyright (C) Wim De Roeve
+ *                based on DHT22 sensor library by HO WING KIT
+ *                Arduino DHT11 library
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documnetation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to  whom the Software is
+ * furished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS OR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * This code has been modified to work with the sensor module
+ */
+
+#ifndef MBED_DHT_H
+#define MBED_DHT_H
+
+#include "Sensor.h"
+#include "mbed.h"
+
+// enum eType { DHT11 = 11, SEN11301P = 11, RHT01 = 11, DHT22 = 22, AM2302 = 22, SEN51035P = 22, RHT02 = 22, RHT03 = 22
+// };
+
+// enum eError {
+//   ERROR_NONE         = 0,
+//   BUS_BUSY           = 1,
+//   ERROR_NOT_PRESENT  = 2,
+//   ERROR_ACK_TOO_LONG = 3,
+//   ERROR_SYNC_TIMEOUT = 4,
+//   ERROR_DATA_TIMEOUT = 5,
+//   ERROR_CHECKSUM     = 6,
+//   ERROR_NO_PATIENCE  = 7
+// };
+
+// typedef enum { CELCIUS = 0, FARENHEIT = 1, KELVIN = 2 } eScale;
+namespace Sensor {
+class DHT final : public Sensor {
+ public:
+  DHT(PinName pin);
+  ~DHT();
+  [[nodiscard]] bool update(void);
+  float read(void);
+  float alternateRead(void);
+  // float CalcdewPoint(float celsius, float humidity);
+  // float CalcdewPointFast(float celsius, float humidity);
+
+ private:
+  time_t _lastReadTime;
+  float _lastTemperature;
+  float _lastHumidity;
+  PinName _pin;
+  bool _firsttime;
+  int _DHTtype;
+  int DHT_data[6];
+  float CalcTemperature();
+  float CalcHumidity();
+  // float ConvertCelciustoFarenheit(float);
+  // float ConvertCelciustoKelvin(float);
+};
+}  // namespace Sensor
+
+#endif

libs/sensors/src/DHT22.cpp

@@ -1,25 +1,224 @@
-#include "DHT22.h"
-
-using namespace Sensor;
-
-DHT22::DHT22(PinName data) : m_data(data) {}
-
-// Returns internal humidity value (and temperature? Since all transmitted at the same time...)
-float DHT22::read() {
-  // Not sure what the mutex is used for, maybe ask later?
-  return m_humidity;
-}
-
-float DHT22::alternateRead() {
-  return m_temperature;
-}
-
-// bool DHT22::getStatus() {}
-
-// bool DHT22::reset() {}
-
-bool DHT22::update() {
-  // need to probably use the DigitalInOut type for getting the data from the sensor
-  // Setup a 2 second loop of sorts? or 80 microseconds? Refer to Arduino code
-  // Needs to check if 2 seconds have been passed already since last call
+/*
+ *  DHT Library for  Digital-output Humidity and Temperature sensors
+ *
+ *  Works with DHT11, DHT22
+ *             SEN11301P,  Grove - Temperature&Humidity Sensor     (Seeed Studio)
+ *             SEN51035P,  Grove - Temperature&Humidity Sensor Pro (Seeed Studio)
+ *             AM2302   ,  temperature-humidity sensor
+ *             HM2303   ,  Digital-output humidity and temperature sensor
+ *
+ *  Copyright (C) Wim De Roeve
+ *                based on DHT22 sensor library by HO WING KIT
+ *                Arduino DHT11 library
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documnetation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to  whom the Software is
+ * furished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS OR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * This code has been modified to work with the sensor module
+ */
+
+#include "DHT.h"
+
+#define DHT_DATA_BIT_COUNT 41
+
+using namespace Sensor;
+
+DHT::DHT(PinName pin) {
+  _pin       = pin;
+  _firsttime = true;
+}
+
+DHT::~DHT() {}
+
+// Reads temparature and relative humidity data from sensor, saves it in corresponding variables
+bool DHT::update() {
+  int i, j, retryCount, b;
+  unsigned int bitTimes[DHT_DATA_BIT_COUNT];
+
+  // eError err         = ERROR_NONE;
+  time_t currentTime = time(NULL);
+
+  DigitalInOut DHT_io(_pin);
+
+  for (i = 0; i < DHT_DATA_BIT_COUNT; i++) {
+    bitTimes[i] = 0;
+  }
+
+  // Only asks for data if more than 2 seconds has lapsed since last call
+  if (!_firsttime) {
+    if (int(currentTime - _lastReadTime) < 2) {
+      // err = ERROR_NO_PATIENCE;
+      return false;
+    }
+  } else {
+    _firsttime    = false;
+    _lastReadTime = currentTime;
+  }
+  retryCount = 0;
+
+  do {
+    if (retryCount > 125) {
+      // err = BUS_BUSY;
+      return false;
+    }
+    retryCount++;
+    wait_us(2);
+  } while ((DHT_io == 0));
+
+  // Send start signal
+  DHT_io.output();
+  DHT_io = 0;
+  wait_us(18000);
+  DHT_io = 1;
+  wait_us(40);
+  DHT_io.input();
+
+  // Fails if no response from sensor
+  retryCount = 0;
+  do {
+    if (retryCount > 40) {
+      // err = ERROR_NOT_PRESENT;
+      return false;
+    }
+    retryCount++;
+    wait_us(1);
+  } while ((DHT_io == 1));
+
+  // if (err != ERROR_NONE) {
+  //   return false;
+  // }
+
+  wait_us(80);
+
+  for (i = 0; i < 5; i++) {
+    for (j = 0; j < 8; j++) {
+      retryCount = 0;
+      do {
+        if (retryCount > 75) {
+          // err = ERROR_DATA_TIMEOUT;
+          return false;
+        }
+        retryCount++;
+        wait_us(1);
+      } while (DHT_io == 0);
+      wait_us(40);
+      bitTimes[i * 8 + j] = DHT_io;
+
+      int count = 0;
+      while (DHT_io == 1 && count < 100) {
+        wait_us(1);
+        count++;
+      }
+    }
+  }
+  DHT_io.output();
+  DHT_io = 1;
+
+  // Populate DHT_data with sensor data
+  for (i = 0; i < 5; i++) {
+    b = 0;
+    for (j = 0; j < 8; j++) {
+      if (bitTimes[i * 8 + j + 1] > 0) {
+        b |= (1 << (7 - j));
+      }
+    }
+    DHT_data[i] = b;
+  }
+
+  if (DHT_data[4] == ((DHT_data[0] + DHT_data[1] + DHT_data[2] + DHT_data[3]) & 0xFF)) {
+    _lastReadTime    = currentTime;
+    _lastTemperature = CalcTemperature();
+    _lastHumidity    = CalcHumidity();
+
+  } else {
+    // err = ERROR_CHECKSUM;
+    return false;
+  }
+
+  return true;
+}
+
+// Map the temperature data from the sensor and return the mapped value
+float DHT::CalcTemperature() {
+  int v;
+
+  v = DHT_data[2] & 0x7F;
+  v *= 256;
+  v += DHT_data[3];
+  v /= 10;
+  if (DHT_data[2] & 0x80) v *= -1;
+  return float(v);
+}
+
+// Return last read humidity value
+float DHT::read() {
+  return _lastHumidity;
+}
+
+// float DHT::ConvertCelciustoFarenheit(float celsius) {
+//   return celsius * 9 / 5 + 32;
+// }
+
+// float DHT::ConvertCelciustoKelvin(float celsius) {
+//   return celsius + 273.15;
+// }
+
+// dewPoint function NOAA
+// reference: http://wahiduddin.net/calc/density_algorithms.htm
+// float DHT::CalcdewPoint(float celsius, float humidity) {
+//   float A0  = 373.15 / (273.15 + celsius);
+//   float SUM = -7.90298 * (A0 - 1);
+//   SUM += 5.02808 * log10(A0);
+//   SUM += -1.3816e-7 * (pow(10, (11.344 * (1 - 1 / A0))) - 1);
+//   SUM += 8.1328e-3 * (pow(10, (-3.49149 * (A0 - 1))) - 1);
+//   SUM += log10(1013.246);
+//   float VP = pow(10, SUM - 3) * humidity;
+//   float T  = log(VP / 0.61078);  // temp var
+//   return (241.88 * T) / (17.558 - T);
+// }
+
+// // delta max = 0.6544 wrt dewPoint()
+// // 5x faster than dewPoint()
+// // reference: http://en.wikipedia.org/wiki/Dew_point
+// float DHT::CalcdewPointFast(float celsius, float humidity) {
+//   float a    = 17.271;
+//   float b    = 237.7;
+//   float temp = (a * celsius) / (b + celsius) + log(humidity / 100);
+//   float Td   = (b * temp) / (a - temp);
+//   return Td;
+// }
+
+// Returns the last read temperature in the wanted scale
+float DHT::alternateRead() {
+  // if (Scale == FARENHEIT)
+  //   return ConvertCelciustoFarenheit(_lastTemperature);
+  // else if (Scale == KELVIN)
+  //   return ConvertCelciustoKelvin(_lastTemperature);
+  // else
+  return _lastTemperature;
+}
+
+float DHT::CalcHumidity() {
+  int v;
+
+  v = DHT_data[0];
+  v *= 256;
+  v += DHT_data[1];
+  v /= 10;
+  return float(v);
 }