A minimal library for the DHT11.
Dependents: EXP10_DHT11_LCD Sushil_MODSERIAL Core1000_SmartFarm idd_summer17_hw3_evey_jenny_seiyoung ... more
Revision 1:5da6f6de3e42, committed 2015-02-16
- Comitter:
- fossum_13
- Date:
- Mon Feb 16 01:43:08 2015 +0000
- Parent:
- 0:c1da310d3e8a
- Commit message:
- Added documentation and some minor improvements. Not backwards compatible!
Changed in this revision
Dht11.cpp | Show annotated file Show diff for this revision Revisions of this file |
Dht11.h | Show annotated file Show diff for this revision Revisions of this file |
diff -r c1da310d3e8a -r 5da6f6de3e42 Dht11.cpp --- a/Dht11.cpp Sun Feb 15 02:09:00 2015 +0000 +++ b/Dht11.cpp Mon Feb 16 01:43:08 2015 +0000 @@ -1,16 +1,15 @@ #include "Dht11.h" -Dht11::Dht11(PinName p) : _pin(p) { +Dht11::Dht11(PinName const &p) : _pin(p) { // Set creation time so we can make // sure we pause at least 1 second for // startup. _timer.start(); + + _temperature = 0; + _humidity = 0; } -// Return values: -// DHTLIB_OK -// DHTLIB_ERROR_CHECKSUM -// DHTLIB_ERROR_TIMEOUT int Dht11::read() { // BUFFER TO RECEIVE @@ -77,10 +76,14 @@ return DHTLIB_OK; } -int Dht11::temperature() { +float Dht11::getFahrenheit() { + return((_temperature * 1.8) + 32); +} + +int Dht11::getCelsius() { return(_temperature); } -int Dht11::humidity() { +int Dht11::getHumidity() { return(_humidity); }
diff -r c1da310d3e8a -r 5da6f6de3e42 Dht11.h --- a/Dht11.h Sun Feb 15 02:09:00 2015 +0000 +++ b/Dht11.h Mon Feb 16 01:43:08 2015 +0000 @@ -7,17 +7,67 @@ #define DHTLIB_ERROR_CHECKSUM -1 #define DHTLIB_ERROR_TIMEOUT -2 -class Dht11 { +/** Class for the DHT11 sensor. + * + * Example: + * @code + * #include "mbed.h" + * #include "Dht11.h" + * + * Serial pc(USBTX, USBRX); + * Dht11 sensor(PTD7); + * + * int main() { + * sensor.read() + * pc.printf("T: %f, H: %d\r\n", sensor.getFahrenheit(), sensor.getHumidity()); + * } + * @endcode + */ +class Dht11 +{ public: - Dht11(PinName p); + /** Construct the sensor object. + * + * @param pin PinName for the sensor pin. + */ + Dht11(PinName const &p); + + /** Update the humidity and temp from the sensor. + * + * @returns + * 0 on success, otherwise error. + */ int read(); - int temperature(); - int humidity(); + + /** Get the temp(f) from the saved object. + * + * @returns + * Fahrenheit float + */ + float getFahrenheit(); + /** Get the temp(c) from the saved object. + * + * @returns + * Celsius int + */ + int getCelsius(); + + /** Get the humidity from the saved object. + * + * @returns + * Humidity percent int + */ + int getHumidity(); + private: + /// percentage of humidity int _humidity; + /// celsius int _temperature; + /// pin to read the sensor info on DigitalInOut _pin; + /// times startup (must settle for at least a second) Timer _timer; };