Update CI action versions

Fix infinite loop on STM32F103

.github/workflows/githubci.yml

@@ -0,0 +1,32 @@
+name: Arduino Library CI
+
+on: [pull_request, push, repository_dispatch]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    
+    steps:
+    - uses: actions/setup-python@v4
+      with:
+        python-version: '3.x'
+    - uses: actions/checkout@v3
+    - uses: actions/checkout@v3
+      with:
+         repository: adafruit/ci-arduino
+         path: ci
+
+    - name: pre-install
+      run: bash ci/actions_install.sh
+
+    - name: test platforms
+      run: python3 ci/build_platform.py main_platforms
+
+    - name: clang
+      run: python3 ci/run-clang-format.py -e "ci/*" -e "bin/*" -r . 
+
+    - name: doxygen
+      env:
+        GH_REPO_TOKEN: ${{ secrets.GH_REPO_TOKEN }}
+        PRETTYNAME : "DHT sensor library"
+      run: bash ci/doxy_gen_and_deploy.sh

.travis.yml

@@ -1,29 +0,0 @@
-language: c
-sudo: false
-
-cache:
-  directories:
-    - ~/arduino_ide
-    - ~/.arduino15/packages/
-
-git:
-  depth: false
-  quiet: true
-
-env:
-  global:
-    - ARDUINO_IDE_VERSION="1.8.7"
-    - PRETTYNAME="DHT sensor library"
-
-before_install:
-  - source <(curl -SLs https://raw.githubusercontent.com/adafruit/travis-ci-arduino/master/install.sh)
-
-install:
-  - arduino --install-library "Adafruit Unified Sensor"
-
-script:
-  - build_main_platforms
-
-after_success:
-  - source <(curl -SLs https://raw.githubusercontent.com/adafruit/travis-ci-arduino/master/library_check.sh)
-  - source <(curl -SLs https://raw.githubusercontent.com/adafruit/travis-ci-arduino/master/doxy_gen_and_deploy.sh)

CONTRIBUTING.md

@@ -0,0 +1,13 @@
+# Contribution Guidlines
+
+This library is the culmination of the expertise of many members of the open source community who have dedicated their time and hard work. The best way to ask for help or propose a new idea is to [create a new issue](https://github.com/adafruit/DHT-sensor-library/issues/new) while creating a Pull Request with your code changes allows you to share your own innovations with the rest of the community.
+
+The following are some guidelines to observe when creating issues or PRs:
+
+- Be friendly; it is important that we can all enjoy a safe space as we are all working on the same project and it is okay for people to have different ideas
+
+- [Use code blocks](https://github.com/adam-p/markdown-here/wiki/Markdown-Cheatsheet#code); it helps us help you when we can read your code! On that note also refrain from pasting more than 30 lines of code in a post, instead [create a gist](https://gist.github.com/) if you need to share large snippets
+
+- Use reasonable titles; refrain from using overly long or capitalized titles as they are usually annoying and do little to encourage others to help :smile:
+
+- Be detailed; refrain from mentioning code problems without sharing your source code and always give information regarding your board and version of the library

DHT.cpp

@@ -26,7 +26,9 @@
 #include "DHT.h"
 
 #define MIN_INTERVAL 2000 /**< min interval value */
-#define TIMEOUT -1        /**< timeout on */
+#define TIMEOUT                                                                \
+  UINT32_MAX /**< Used programmatically for timeout.                           \
+                   Not a timeout duration. Type: uint32_t. */
 
 /*!
  *  @brief  Instantiates a new DHT class
@@ -38,6 +40,7 @@
  *          number of sensors
  */
 DHT::DHT(uint8_t pin, uint8_t type, uint8_t count) {
+  (void)count; // Workaround to avoid compiler warning.
   _pin = pin;
   _type = type;
 #ifdef __AVR
@@ -164,8 +167,8 @@ float DHT::readHumidity(bool force) {
  *  @brief  Compute Heat Index
  *          Simplified version that reads temp and humidity from sensor
  *  @param  isFahrenheit
- * 					true if fahrenheit, false if celcius (default
- *true)
+ * 					true if fahrenheit, false if celcius
+ *(default true)
  *	@return float heat index
  */
 float DHT::computeHeatIndex(bool isFahrenheit) {
@@ -357,7 +360,9 @@ bool DHT::read(bool force) {
 // in the very latest IDE versions):
 //   https://github.com/arduino/Arduino/blob/master/hardware/arduino/avr/cores/arduino/wiring_pulse.c
 uint32_t DHT::expectPulse(bool level) {
-#if (F_CPU > 16000000L)
+// F_CPU is not be known at compile time on platforms such as STM32F103.
+// The preprocessor seems to evaluate it to zero in that case.
+#if (F_CPU > 16000000L) || (F_CPU == 0L)
   uint32_t count = 0;
 #else
   uint16_t count = 0; // To work fast enough on slower AVR boards

DHT.h

@@ -3,7 +3,8 @@
  *
  *  This is a library for DHT series of low cost temperature/humidity sensors.
  *
- *  You must have Adafruit Unified Sensor Library library installed to use this class.
+ *  You must have Adafruit Unified Sensor Library library installed to use this
+ * class.
  *
  *  Adafruit invests time and resources providing this open source code,
  *  please support Adafruit andopen-source hardware by purchasing products
@@ -22,71 +23,87 @@
 /* Uncomment to enable printing out nice debug messages. */
 //#define DHT_DEBUG
 
-
-#define DEBUG_PRINTER Serial /**< Define where debug output will be printed. */
+#define DEBUG_PRINTER                                                          \
+  Serial /**< Define where debug output will be printed.                       \
+          */
 
 /* Setup debug printing macros. */
 #ifdef DHT_DEBUG
-  #define DEBUG_PRINT(...) { DEBUG_PRINTER.print(__VA_ARGS__); }
-  #define DEBUG_PRINTLN(...) { DEBUG_PRINTER.println(__VA_ARGS__); }
+#define DEBUG_PRINT(...)                                                       \
+  { DEBUG_PRINTER.print(__VA_ARGS__); }
+#define DEBUG_PRINTLN(...)                                                     \
+  { DEBUG_PRINTER.println(__VA_ARGS__); }
 #else
-  #define DEBUG_PRINT(...) {} /**< Debug Print Placeholder if Debug is disabled */
-  #define DEBUG_PRINTLN(...) {} /**< Debug Print Line Placeholder if Debug is disabled */
+#define DEBUG_PRINT(...)                                                       \
+  {} /**< Debug Print Placeholder if Debug is disabled */
+#define DEBUG_PRINTLN(...)                                                     \
+  {} /**< Debug Print Line Placeholder if Debug is disabled */
 #endif
 
 /* Define types of sensors. */
-#define DHT11 11 /**< DHT TYPE 11 */
-#define DHT12 12 /**< DHY TYPE 12 */
-#define DHT22 22 /**< DHT TYPE 22 */
-#define DHT21 21 /**< DHT TYPE 21 */
-#define AM2301 21 /**< AM2301 */
+static const uint8_t DHT11{11};  /**< DHT TYPE 11 */
+static const uint8_t DHT12{12};  /**< DHY TYPE 12 */
+static const uint8_t DHT21{21};  /**< DHT TYPE 21 */
+static const uint8_t DHT22{22};  /**< DHT TYPE 22 */
+static const uint8_t AM2301{21}; /**< AM2301 */
 
-/*! 
+#if defined(TARGET_NAME) && (TARGET_NAME == ARDUINO_NANO33BLE)
+#ifndef microsecondsToClockCycles
+/*!
+ * As of 7 Sep 2020 the Arduino Nano 33 BLE boards do not have
+ * microsecondsToClockCycles defined.
+ */
+#define microsecondsToClockCycles(a) ((a) * (SystemCoreClock / 1000000L))
+#endif
+#endif
+
+/*!
  *  @brief  Class that stores state and functions for DHT
  */
 class DHT {
-  public:
-   DHT(uint8_t pin, uint8_t type, uint8_t count=6);
-   void begin(uint8_t usec=55);
-   float readTemperature(bool S=false, bool force=false);
-   float convertCtoF(float);
-   float convertFtoC(float);
-   float computeHeatIndex(bool isFahrenheit=true);
-   float computeHeatIndex(float temperature, float percentHumidity, bool isFahrenheit=true);
-   float readHumidity(bool force=false);
-   bool read(bool force=false);
+public:
+  DHT(uint8_t pin, uint8_t type, uint8_t count = 6);
+  void begin(uint8_t usec = 55);
+  float readTemperature(bool S = false, bool force = false);
+  float convertCtoF(float);
+  float convertFtoC(float);
+  float computeHeatIndex(bool isFahrenheit = true);
+  float computeHeatIndex(float temperature, float percentHumidity,
+                         bool isFahrenheit = true);
+  float readHumidity(bool force = false);
+  bool read(bool force = false);
 
- private:
+private:
   uint8_t data[5];
   uint8_t _pin, _type;
-  #ifdef __AVR
-    // Use direct GPIO access on an 8-bit AVR so keep track of the port and bitmask
-    // for the digital pin connected to the DHT.  Other platforms will use digitalRead.
-    uint8_t _bit, _port;
-  #endif
+#ifdef __AVR
+  // Use direct GPIO access on an 8-bit AVR so keep track of the port and
+  // bitmask for the digital pin connected to the DHT.  Other platforms will use
+  // digitalRead.
+  uint8_t _bit, _port;
+#endif
   uint32_t _lastreadtime, _maxcycles;
   bool _lastresult;
   uint8_t pullTime; // Time (in usec) to pull up data line before reading
 
   uint32_t expectPulse(bool level);
-
 };
 
-/*! 
+/*!
  *  @brief  Class that defines Interrupt Lock Avaiability
  */
 class InterruptLock {
-  public:
-   InterruptLock() {
-#if !defined(ARDUINO_ARCH_NRF52)  
+public:
+  InterruptLock() {
+#if !defined(ARDUINO_ARCH_NRF52)
     noInterrupts();
 #endif
-   }
-   ~InterruptLock() {
-#if !defined(ARDUINO_ARCH_NRF52)  
+  }
+  ~InterruptLock() {
+#if !defined(ARDUINO_ARCH_NRF52)
     interrupts();
 #endif
-   }
+  }
 };
 
 #endif

DHT_U.cpp

@@ -27,46 +27,43 @@
  *  @param  humiditySensorId
  *          humidity sensor id
  */
-DHT_Unified::DHT_Unified(uint8_t pin, uint8_t type, uint8_t count, int32_t tempSensorId, int32_t humiditySensorId):
-  _dht(pin, type, count),
-  _type(type),
-  _temp(this, tempSensorId),
-  _humidity(this, humiditySensorId)
-{}
+DHT_Unified::DHT_Unified(uint8_t pin, uint8_t type, uint8_t count,
+                         int32_t tempSensorId, int32_t humiditySensorId)
+    : _dht(pin, type, count), _type(type), _temp(this, tempSensorId),
+      _humidity(this, humiditySensorId) {}
 
 /*!
  *  @brief  Setup sensor (calls begin on It)
  */
-void DHT_Unified::begin() {
-  _dht.begin();
-}
+void DHT_Unified::begin() { _dht.begin(); }
 
 /*!
  *  @brief  Sets sensor name
  *  @param  sensor
  *          Sensor that will be set
  */
-void DHT_Unified::setName(sensor_t* sensor) {
-  switch(_type) {
-    case DHT11:
-      strncpy(sensor->name, "DHT11", sizeof(sensor->name) - 1);
-      break;
-    case DHT12:
-      strncpy(sensor->name, "DHT12", sizeof(sensor->name) - 1);
-      break;
-    case DHT21:
-      strncpy(sensor->name, "DHT21", sizeof(sensor->name) - 1);
-      break;
-    case DHT22:
-      strncpy(sensor->name, "DHT22", sizeof(sensor->name) - 1);
-      break;
-    default:
-      // TODO: Perhaps this should be an error?  However main DHT library doesn't enforce
-      // restrictions on the sensor type value.  Pick a generic name for now.
-      strncpy(sensor->name, "DHT?", sizeof(sensor->name) - 1);
-      break;
+void DHT_Unified::setName(sensor_t *sensor) {
+  switch (_type) {
+  case DHT11:
+    strncpy(sensor->name, "DHT11", sizeof(sensor->name) - 1);
+    break;
+  case DHT12:
+    strncpy(sensor->name, "DHT12", sizeof(sensor->name) - 1);
+    break;
+  case DHT21:
+    strncpy(sensor->name, "DHT21", sizeof(sensor->name) - 1);
+    break;
+  case DHT22:
+    strncpy(sensor->name, "DHT22", sizeof(sensor->name) - 1);
+    break;
+  default:
+    // TODO: Perhaps this should be an error?  However main DHT library doesn't
+    // enforce restrictions on the sensor type value.  Pick a generic name for
+    // now.
+    strncpy(sensor->name, "DHT?", sizeof(sensor->name) - 1);
+    break;
   }
-  sensor->name[sizeof(sensor->name)- 1] = 0;
+  sensor->name[sizeof(sensor->name) - 1] = 0;
 }
 
 /*!
@@ -74,24 +71,24 @@ void DHT_Unified::setName(sensor_t* sensor) {
  *  @param  sensor
  *          Sensor that will be set
  */
-void DHT_Unified::setMinDelay(sensor_t* sensor) {
-  switch(_type) {
-    case DHT11:
-      sensor->min_delay = 1000000L;  // 1 second (in microseconds)
-      break;
-    case DHT12:
-      sensor->min_delay = 2000000L;  // 2 second (in microseconds)
-      break;
-    case DHT21:
-      sensor->min_delay = 2000000L;  // 2 seconds (in microseconds)
-      break;
-    case DHT22:
-      sensor->min_delay = 2000000L;  // 2 seconds (in microseconds)
-      break;
-    default:
-      // Default to slowest sample rate in case of unknown type.
-      sensor->min_delay = 2000000L;  // 2 seconds (in microseconds)
-      break;
+void DHT_Unified::setMinDelay(sensor_t *sensor) {
+  switch (_type) {
+  case DHT11:
+    sensor->min_delay = 1000000L; // 1 second (in microseconds)
+    break;
+  case DHT12:
+    sensor->min_delay = 2000000L; // 2 second (in microseconds)
+    break;
+  case DHT21:
+    sensor->min_delay = 2000000L; // 2 seconds (in microseconds)
+    break;
+  case DHT22:
+    sensor->min_delay = 2000000L; // 2 seconds (in microseconds)
+    break;
+  default:
+    // Default to slowest sample rate in case of unknown type.
+    sensor->min_delay = 2000000L; // 2 seconds (in microseconds)
+    break;
   }
 }
 
@@ -102,26 +99,24 @@ void DHT_Unified::setMinDelay(sensor_t* sensor) {
  *  @param  id
  *          Sensor id
  */
-DHT_Unified::Temperature::Temperature(DHT_Unified* parent, int32_t id):
-  _parent(parent),
-  _id(id)
-{}
+DHT_Unified::Temperature::Temperature(DHT_Unified *parent, int32_t id)
+    : _parent(parent), _id(id) {}
 
 /*!
  *  @brief  Reads the sensor and returns the data as a sensors_event_t
  *  @param  event
  *  @return always returns true
  */
-bool DHT_Unified::Temperature::getEvent(sensors_event_t* event) {
+bool DHT_Unified::Temperature::getEvent(sensors_event_t *event) {
   // Clear event definition.
   memset(event, 0, sizeof(sensors_event_t));
   // Populate sensor reading values.
-  event->version     = sizeof(sensors_event_t);
-  event->sensor_id   = _id;
-  event->type        = SENSOR_TYPE_AMBIENT_TEMPERATURE;
-  event->timestamp   = millis();
+  event->version = sizeof(sensors_event_t);
+  event->sensor_id = _id;
+  event->type = SENSOR_TYPE_AMBIENT_TEMPERATURE;
+  event->timestamp = millis();
   event->temperature = _parent->_dht.readTemperature();
-  
+
   return true;
 }
 
@@ -129,44 +124,44 @@ bool DHT_Unified::Temperature::getEvent(sensors_event_t* event) {
  *  @brief  Provides the sensor_t data for this sensor
  *  @param  sensor
  */
-void DHT_Unified::Temperature::getSensor(sensor_t* sensor) {
+void DHT_Unified::Temperature::getSensor(sensor_t *sensor) {
   // Clear sensor definition.
   memset(sensor, 0, sizeof(sensor_t));
   // Set sensor name.
   _parent->setName(sensor);
   // Set version and ID
-  sensor->version         = DHT_SENSOR_VERSION;
-  sensor->sensor_id       = _id;
+  sensor->version = DHT_SENSOR_VERSION;
+  sensor->sensor_id = _id;
   // Set type and characteristics.
-  sensor->type            = SENSOR_TYPE_AMBIENT_TEMPERATURE;
+  sensor->type = SENSOR_TYPE_AMBIENT_TEMPERATURE;
   _parent->setMinDelay(sensor);
   switch (_parent->_type) {
-    case DHT11:
-      sensor->max_value   = 50.0F;
-      sensor->min_value   = 0.0F;
-      sensor->resolution  = 2.0F;
-      break;
-    case DHT12:
-      sensor->max_value   = 60.0F;
-      sensor->min_value   = -20.0F;
-      sensor->resolution  = 0.5F;
-      break;
-    case DHT21:
-      sensor->max_value   = 80.0F;
-      sensor->min_value   = -40.0F;
-      sensor->resolution  = 0.1F;
-      break;
-    case DHT22:
-      sensor->max_value   = 125.0F;
-      sensor->min_value   = -40.0F;
-      sensor->resolution  = 0.1F;
-      break;
-    default:
-      // Unknown type, default to 0.
-      sensor->max_value   = 0.0F;
-      sensor->min_value   = 0.0F;
-      sensor->resolution  = 0.0F;
-      break;
+  case DHT11:
+    sensor->max_value = 50.0F;
+    sensor->min_value = 0.0F;
+    sensor->resolution = 2.0F;
+    break;
+  case DHT12:
+    sensor->max_value = 60.0F;
+    sensor->min_value = -20.0F;
+    sensor->resolution = 0.5F;
+    break;
+  case DHT21:
+    sensor->max_value = 80.0F;
+    sensor->min_value = -40.0F;
+    sensor->resolution = 0.1F;
+    break;
+  case DHT22:
+    sensor->max_value = 125.0F;
+    sensor->min_value = -40.0F;
+    sensor->resolution = 0.1F;
+    break;
+  default:
+    // Unknown type, default to 0.
+    sensor->max_value = 0.0F;
+    sensor->min_value = 0.0F;
+    sensor->resolution = 0.0F;
+    break;
   }
 }
 
@@ -177,26 +172,24 @@ void DHT_Unified::Temperature::getSensor(sensor_t* sensor) {
  *  @param  id
  *          Sensor id
  */
-DHT_Unified::Humidity::Humidity(DHT_Unified* parent, int32_t id):
-  _parent(parent),
-  _id(id)
-{}
+DHT_Unified::Humidity::Humidity(DHT_Unified *parent, int32_t id)
+    : _parent(parent), _id(id) {}
 
 /*!
  *  @brief  Reads the sensor and returns the data as a sensors_event_t
  *  @param  event
  *  @return always returns true
  */
-bool DHT_Unified::Humidity::getEvent(sensors_event_t* event) {
+bool DHT_Unified::Humidity::getEvent(sensors_event_t *event) {
   // Clear event definition.
   memset(event, 0, sizeof(sensors_event_t));
   // Populate sensor reading values.
-  event->version           = sizeof(sensors_event_t);
-  event->sensor_id         = _id;
-  event->type              = SENSOR_TYPE_RELATIVE_HUMIDITY;
-  event->timestamp         = millis();
+  event->version = sizeof(sensors_event_t);
+  event->sensor_id = _id;
+  event->type = SENSOR_TYPE_RELATIVE_HUMIDITY;
+  event->timestamp = millis();
   event->relative_humidity = _parent->_dht.readHumidity();
-  
+
   return true;
 }
 
@@ -204,43 +197,43 @@ bool DHT_Unified::Humidity::getEvent(sensors_event_t* event) {
  *  @brief  Provides the sensor_t data for this sensor
  *  @param  sensor
  */
-void DHT_Unified::Humidity::getSensor(sensor_t* sensor) {
+void DHT_Unified::Humidity::getSensor(sensor_t *sensor) {
   // Clear sensor definition.
   memset(sensor, 0, sizeof(sensor_t));
   // Set sensor name.
   _parent->setName(sensor);
   // Set version and ID
-  sensor->version         = DHT_SENSOR_VERSION;
-  sensor->sensor_id       = _id;
+  sensor->version = DHT_SENSOR_VERSION;
+  sensor->sensor_id = _id;
   // Set type and characteristics.
-  sensor->type            = SENSOR_TYPE_RELATIVE_HUMIDITY;
+  sensor->type = SENSOR_TYPE_RELATIVE_HUMIDITY;
   _parent->setMinDelay(sensor);
   switch (_parent->_type) {
-    case DHT11:
-      sensor->max_value   = 80.0F;
-      sensor->min_value   = 20.0F;
-      sensor->resolution  = 5.0F;
-      break;
-    case DHT12:
-      sensor->max_value   = 95.0F;
-      sensor->min_value   = 20.0F;
-      sensor->resolution  = 5.0F;
-      break;
-    case DHT21:
-      sensor->max_value   = 100.0F;
-      sensor->min_value   = 0.0F;
-      sensor->resolution  = 0.1F;
-      break;
-    case DHT22:
-      sensor->max_value   = 100.0F;
-      sensor->min_value   = 0.0F;
-      sensor->resolution  = 0.1F;
-      break;
-    default:
-      // Unknown type, default to 0.
-      sensor->max_value   = 0.0F;
-      sensor->min_value   = 0.0F;
-      sensor->resolution  = 0.0F;
-      break;
+  case DHT11:
+    sensor->max_value = 80.0F;
+    sensor->min_value = 20.0F;
+    sensor->resolution = 5.0F;
+    break;
+  case DHT12:
+    sensor->max_value = 95.0F;
+    sensor->min_value = 20.0F;
+    sensor->resolution = 5.0F;
+    break;
+  case DHT21:
+    sensor->max_value = 100.0F;
+    sensor->min_value = 0.0F;
+    sensor->resolution = 0.1F;
+    break;
+  case DHT22:
+    sensor->max_value = 100.0F;
+    sensor->min_value = 0.0F;
+    sensor->resolution = 0.1F;
+    break;
+  default:
+    // Unknown type, default to 0.
+    sensor->max_value = 0.0F;
+    sensor->min_value = 0.0F;
+    sensor->resolution = 0.0F;
+    break;
   }
 }

DHT_U.h

@@ -76,13 +76,13 @@ public:
     int32_t _id;
   };
 
-	/*!
+  /*!
    *  @brief  Returns temperature stored in _temp
    *  @return Temperature value
    */
   Temperature temperature() { return _temp; }
 
-	/*!
+  /*!
    *  @brief  Returns humidity stored in _humidity
    *  @return Humidity value
    */

README.md

@@ -1,14 +1,58 @@
-# Adafruit DHT Humidity & Temperature Sensor Library [![Build Status](https://travis-ci.com/adafruit/DHT-sensor-library.svg?branch=master)](https://travis-ci.com/adafruit/DHT-sensor-library)
+# DHT sensor library [![Build Status](https://github.com/adafruit/DHT-sensor-library/workflows/Arduino%20Library%20CI/badge.svg)](https://github.com/adafruit/DHT-sensor-library/actions)
 
-An Arduino library for the DHT series of low cost temperature/humidity sensors.
+## Description
 
-Tutorial: https://learn.adafruit.com/dht
+An Arduino library for the DHT series of low-cost temperature/humidity sensors.
 
-**You must have the following Arduino libraries installed to use this class:**
+You can find DHT tutorials [here](https://learn.adafruit.com/dht).
 
-- [Adafruit Unified Sensor Library](https://github.com/adafruit/Adafruit_Sensor)
+# Dependencies
+ * [Adafruit Unified Sensor Driver](https://github.com/adafruit/Adafruit_Sensor)
 
-Examples include both a "standalone" DHT example, and one that works along with the Adafruit Unified Sensor Library. Unified sensor library is required even if using the standalone version.
+# Contributing
 
-Recent Arduino IDE releases include the Library Manager for easy installation. Otherwise, to download, click the DOWNLOADS button in the top right corner, rename the uncompressed folder DHT. Check that the DHT folder contains DHT.cpp and DHT.h. Place the DHT library folder your <arduinosketchfolder>/libraries/ folder. You may need to create the libraries subfolder if its your first library. Restart the IDE.
+Contributions are welcome!  Not only you’ll encourage the development of the library, but you’ll also learn how to best use the library and probably some C++ too
 
+Please read our [Code of Conduct](https://github.com/adafruit/DHT-sensor-library/blob/master/CODE_OF_CONDUCT.md>)
+before contributing to help this project stay welcoming.
+
+## Documentation and doxygen
+Documentation is produced by doxygen. Contributions should include documentation for any new code added.
+
+Some examples of how to use doxygen can be found in these guide pages:
+
+https://learn.adafruit.com/the-well-automated-arduino-library/doxygen
+
+https://learn.adafruit.com/the-well-automated-arduino-library/doxygen-tips
+
+Written by Adafruit Industries based on work by:
+
+ * T. DiCola
+ * P. Y. Dragon
+ * L. Fried
+ * J. Hoffmann
+ * M. Kooijman
+ * J. M. Dana
+ * S. Conaway
+ * S. IJskes
+ * T. Forbes
+ * B. C
+ * T. J Myers
+ * L. Sørup
+ * per1234
+ * O. Duffy
+ * matthiasdanner
+ * J. Lim
+ * G. Ambrozio
+ * chelmi
+ * adams13x13
+ * Spacefish
+ * I. Scheller
+ * C. Miller
+ * 7eggert
+
+
+MIT license, check license.txt for more information
+All text above must be included in any redistribution
+
+To install, use the Arduino Library Manager and search for "DHT sensor library" and install the library.

code-of-conduct.md

@@ -0,0 +1,127 @@
+# Adafruit Community Code of Conduct
+
+## Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as
+contributors and leaders pledge to making participation in our project and
+our community a harassment-free experience for everyone, regardless of age, body
+size, disability, ethnicity, gender identity and expression, level or type of
+experience, education, socio-economic status, nationality, personal appearance,
+race, religion, or sexual identity and orientation.
+
+## Our Standards
+
+We are committed to providing a friendly, safe and welcoming environment for
+all.
+
+Examples of behavior that contributes to creating a positive environment
+include:
+
+* Be kind and courteous to others
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Collaborating with other community members
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members
+
+Examples of unacceptable behavior by participants include:
+
+* The use of sexualized language or imagery and sexual attention or advances
+* The use of inappropriate images, including in a community member's avatar
+* The use of inappropriate language, including in a community member's nickname
+* Any spamming, flaming, baiting or other attention-stealing behavior
+* Excessive or unwelcome helping; answering outside the scope of the question
+  asked
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic
+  address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate
+
+The goal of the standards and moderation guidelines outlined here is to build
+and maintain a respectful community. We ask that you don’t just aim to be
+"technically unimpeachable", but rather try to be your best self. 
+
+We value many things beyond technical expertise, including collaboration and
+supporting others within our community. Providing a positive experience for
+other community members can have a much more significant impact than simply
+providing the correct answer.
+
+## Our Responsibilities
+
+Project leaders are responsible for clarifying the standards of acceptable
+behavior and are expected to take appropriate and fair corrective action in
+response to any instances of unacceptable behavior.
+
+Project leaders have the right and responsibility to remove, edit, or
+reject messages, comments, commits, code, issues, and other contributions
+that are not aligned to this Code of Conduct, or to ban temporarily or
+permanently any community member for other behaviors that they deem
+inappropriate, threatening, offensive, or harmful.
+
+## Moderation
+
+Instances of behaviors that violate the Adafruit Community Code of Conduct
+may be reported by any member of the community. Community members are
+encouraged to report these situations, including situations they witness
+involving other community members.
+
+You may report in the following ways:
+
+In any situation, you may send an email to <support@adafruit.com>.
+
+On the Adafruit Discord, you may send an open message from any channel
+to all Community Helpers by tagging @community helpers. You may also send an
+open message from any channel, or a direct message to @kattni#1507,
+@tannewt#4653, @Dan Halbert#1614, @cater#2442, @sommersoft#0222, or
+@Andon#8175.
+
+Email and direct message reports will be kept confidential.
+
+In situations on Discord where the issue is particularly egregious, possibly
+illegal, requires immediate action, or violates the Discord terms of service,
+you should also report the message directly to Discord.
+
+These are the steps for upholding our community’s standards of conduct.
+
+1. Any member of the community may report any situation that violates the
+Adafruit Community Code of Conduct. All reports will be reviewed and
+investigated.
+2. If the behavior is an egregious violation, the community member who
+committed the violation may be banned immediately, without warning.
+3. Otherwise, moderators will first respond to such behavior with a warning.
+4. Moderators follow a soft "three strikes" policy - the community member may
+be given another chance, if they are receptive to the warning and change their
+behavior.
+5. If the community member is unreceptive or unreasonable when warned by a
+moderator, or the warning goes unheeded, they may be banned for a first or
+second offense. Repeated offenses will result in the community member being
+banned.
+
+## Scope
+
+This Code of Conduct and the enforcement policies listed above apply to all
+Adafruit Community venues. This includes but is not limited to any community
+spaces (both public and private), the entire Adafruit Discord server, and
+Adafruit GitHub repositories. Examples of Adafruit Community spaces include
+but are not limited to meet-ups, audio chats on the Adafruit Discord, or
+interaction at a conference.
+
+This Code of Conduct applies both within project spaces and in public spaces
+when an individual is representing the project or its community. As a community
+member, you are representing our community, and are expected to behave
+accordingly.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage],
+version 1.4, available at
+<https://www.contributor-covenant.org/version/1/4/code-of-conduct.html>,
+and the [Rust Code of Conduct](https://www.rust-lang.org/en-US/conduct.html).
+
+For other projects adopting the Adafruit Community Code of
+Conduct, please contact the maintainers of those projects for enforcement.
+If you wish to use this code of conduct for your own project, consider
+explicitly mentioning your moderation policy or making a copy with your
+own moderation policy so as to avoid confusion.

examples/DHTtester/DHTtester.ino

@@ -20,7 +20,8 @@
 // NOTE: If using a board with 3.3V logic like an Arduino Due connect pin 1
 // to 3.3V instead of 5V!
 // Connect pin 2 of the sensor to whatever your DHTPIN is
-// Connect pin 4 (on the right) of the sensor to GROUND
+// Connect pin 3 (on the right) of the sensor to GROUND (if your sensor has 3 pins)
+// Connect pin 4 (on the right) of the sensor to GROUND and leave the pin 3 EMPTY (if your sensor has 4 pins)
 // Connect a 10K resistor from pin 2 (data) to pin 1 (power) of the sensor
 
 // Initialize DHT sensor.

library.properties

@@ -1,5 +1,5 @@
 name=DHT sensor library
-version=1.3.7
+version=1.4.4
 author=Adafruit
 maintainer=Adafruit <info@adafruit.com>
 sentence=Arduino library for DHT11, DHT22, etc Temp & Humidity Sensors

license.txt

@@ -0,0 +1,20 @@
+Copyright (c) 2020 Adafruit Industries
+
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation 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
+furnished 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 FOR 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.