Diff: DHT11.h

Revision:

13:11d0770eb603

Parent:

12:af1eadec17e5

--- a/DHT11.h	Mon May 31 07:02:00 2021 +0000
+++ b/DHT11.h	Wed Sep 15 14:47:06 2021 +0000
@@ -29,14 +29,7 @@
  *
  * main()
  * {
- *     int s;
- *     s = d.readData();
- *     if (s != DHT11::OK) {
- *         printf("Error!\r\n");
- *     }
- *     else {
- *         printf("T:%d, H:%d\r\n", d.readTemperature(), d.readHumidity());
- *     }
+ *     printf("T:%d, H:%d\r\n", d.readTemperature(), d.readHumidity());
  * }
  * @endcode
  */
@@ -50,7 +43,8 @@
     DHT11(PinName pin);
     ~DHT11();
 
-    /** Reading the data from the DHT11
+    /** Reading the data from the DHT11.  Calling this is not required, but
+     * may be useful for debug.
      * @return Error code
      *     0: OK.
      *     1: Reading the data too often.
@@ -62,15 +56,17 @@
      */
     int readData(void);
 
-    /** Reading the humidity from the data
-     * @return Humidity in %,
-     * regardless of the error from readData()
+    /** Returns the current humidity from the DHT11.  If the existing data record
+     * is older than 2000ms, initiates a read from the device.  Note that errors
+     * may result in infinite attempts to read.
+     * @return Humidity in %
      */
     int readHumidity(void);
 
-    /** Reading the temperature from the data
-     * @return Temperature in Celcius,
-     * regardless of the error from readData()
+    /** Returns the current temperature from the DHT11.  If the existing data record
+     * is older than 2000ms, initiates a read from the device.  Note that errors
+     * may result in infinite attempts to read.
+     * @return Temperature in Celcius
      */
     int readTemperature(void);
 
@@ -91,7 +87,6 @@
     uint32_t t_pulse_us;
     const static int t_tol_start;    
     const static int t_tol_pulse;
-    bool first_time;
     uint64_t data;
     uint32_t chksum;
     uint32_t cnt;
@@ -100,6 +95,7 @@
     void init(void);
     void pos_edge(void);
     void neg_edge(void);
+    void readNewData(void);
 };
 
 #endif
\ No newline at end of file