Diff: AM2321.h

Revision:

0:d1c0dbf5e5a6

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/AM2321.h	Tue May 06 10:21:11 2014 +0000
@@ -0,0 +1,79 @@
+/**
+ *  AM2321 (Aosong Guangzhou Electronics)
+ *  Temperature and Humidity Sensor mbed library
+ *  Last update : 2014/05/06
+ */
+
+#ifndef __AM2321_H__
+#define __AM2321_H__
+
+/** AM2321 (Aosong Guangzhou Electronics)
+ * Temperature and Humidity Sensor mbed library
+ * 
+ * Example:
+ * @code
+ * #include "mbed.h"
+ * #include "AM2321.h"
+ *
+ * Serial pc(USBTX, USBRX);    // Tx, Rx
+ * AM2321 am2321(p28, p27);    // SDA, SCL
+ *
+ * int main()
+ * {
+ *     while(1)
+ *     {
+ *        if(am2321.poll())
+ *         {
+ *             pc.printf(":%05u,%.1f,%.1f\n"
+ *                 , count++
+ *                 , am2321.getTemperature()
+ *                 , am2321.getHumidity()
+ *             );
+ *         }
+ * 
+ *         wait(0.5);
+ *     }
+ * }
+ * @endcode
+ */
+class AM2321
+{
+private:
+    typedef struct tagRESULT
+    {
+        float temperature;
+        float humidity;
+    }RESULT;
+
+public:
+    /** Constructor
+     * @param   sda  [in]    I2C Pin name (SDA)
+     * @param   scl  [in]    I2C Pin name (SCL)
+     */
+    AM2321(PinName sda, PinName scl);
+    
+    /** Read current temperature and humidity from AM2321
+     * @return  result (true=success)
+     */
+    bool poll();
+
+    /** Get last read temperature value
+     * @return  temperature value (degress)
+     */
+    float getTemperature(void) const;
+    
+    /** Get last read humidity value
+     * @return  humidity value (%RH)
+     */ 
+    float getHumidity(void) const;
+
+private:
+    float getLogicalValue(uint16_t regVal) const;
+    uint16_t calcCRC16(const uint8_t* src, int len) const;
+
+    I2C    _i2c;
+    RESULT _result;
+};
+
+
+#endif // __AM2321_H__