Diff: Dht22.h

Revision:

2:cc518592dbdb

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Dht22.h	Fri Nov 10 01:00:56 2017 +0000
@@ -0,0 +1,74 @@
+#ifndef DHT22_H
+#define DHT22_H
+
+#include "mbed.h"
+
+#define DHTLIB_OK                0
+#define DHTLIB_ERROR_CHECKSUM   -1
+#define DHTLIB_ERROR_TIMEOUT    -2
+
+/** Class for the DHT22 sensor.
+ * 
+ * Example:
+ * @code
+ * #include "mbed.h"
+ * #include "Dht22.h"
+ *
+ * Serial pc(USBTX, USBRX);
+ * Dht22 sensor(PTD7);
+ * 
+ * int main() {
+ *     sensor.read()
+ *     pc.printf("T: %f, H: %d\r\n", sensor.getFahrenheit(), sensor.getHumidity());
+ * }
+ * @endcode
+ */
+class Dht22
+{
+public:
+    /** Construct the sensor object.
+     *
+     * @param pin PinName for the sensor pin.
+     */
+    Dht22(PinName const &p);
+    
+    /** Update the humidity and temp from the sensor.
+     *
+     * @returns
+     *   0 on success, otherwise error.
+     */
+    int read();
+    
+    /** 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;
+};
+
+#endif