Revision 1:cc6bfdd667ea, committed 2016-03-17

Comitter:

stevew817

Date:

Thu Mar 17 11:33:02 2016 +0000

Parent:

0:2629b8684f00

Commit message:

Update measurement algo

Changed in this revision

diff -r 2629b8684f00 -r cc6bfdd667ea main.cpp
--- a/main.cpp	Thu Mar 17 08:44:50 2016 +0000
+++ b/main.cpp	Thu Mar 17 11:33:02 2016 +0000
@@ -7,8 +7,10 @@
 /** @cond DO_NOT_INCLUDE_WITH_DOXYGEN */
  
 /** Si7013 Read Temperature Command */
-#define SI7013_READ_TEMP        0xE0 /* Read previous T data from RH measurement
+#define SI7013_READ_TEMP_POST   0xE0 /* Read previous T data from RH measurement
                                         command*/
+#define SI7013_READ_TEMP        0xE3 /* Stand-alone read temperature command */
+
 /** Si7013 Read RH Command */
 #define SI7013_READ_RH          0xE5 /* Perform RH (and T) measurement. */
 /** Si7013 Read ID */
@@ -57,20 +59,32 @@
  *******************************     FUNC    ***********************************
  ******************************************************************************/
 
-int32_t readTemperature(void) {
+void readSensor(void) {
     int temp = 0;
+    unsigned int humidity = 0;
+    
+    //send humidity command
+    _tx_buf[0] = SI7013_READ_RH;
+    tempSensor.write(_address, (char*)_tx_buf, 1);
+    tempSensor.read(_address, (char*)_rx_buf, 2);
+    
+    /* Store raw RH info */
+    humidity = ((uint32_t)_rx_buf[0] << 8) + (_rx_buf[1] & 0xFC);
+    /* Convert value to milli-percent */
+    humidity = (((humidity) * 15625L) >> 13) - 6000;
     
     //send temperature command
-    _tx_buf[0] = SI7013_READ_TEMP;
+    _tx_buf[0] = SI7013_READ_TEMP_POST;
     tempSensor.write(_address, (char*)_tx_buf, 1);
     tempSensor.read(_address, (char*)_rx_buf, 2);
     
     /* Store raw temperature info */
     temp = ((uint32_t)_rx_buf[0] << 8) + (_rx_buf[1] & 0xFC);
     /* Convert to milli-degC */
-    temp = (((_tData) * 21965L) >> 13) - 46850;
+    temp = (((temp) * 21965L) >> 13) - 46850;
     
-    return temp;
+    _tData = temp;
+    _rhData = humidity;
 } 
 
 int main() {
@@ -93,7 +107,7 @@
     
     while(1) {
         wait(1);
-        _tData = readTemperature();
+        readSensor();
         printf("Temperature: %d,%3d\r\n", _tData / 1000, _tData % 1000);
     }
 }
\ No newline at end of file