Diff: omegaPX209/omegaPX209.hpp

Revision:

14:85b64a4d08e8

Parent:

10:085ab7328054

Child:

17:7c16b5671d0e

--- a/omegaPX209/omegaPX209.hpp	Mon Oct 30 21:09:19 2017 +0000
+++ b/omegaPX209/omegaPX209.hpp	Tue Oct 31 17:06:52 2017 +0000
@@ -1,27 +1,37 @@
 /*
-Matthew Kelly
-October 24th, 2013
-The purpose of this class is to define a a data structure with all of the necessary information and member functions...
-to fully describe a single ultrasonic transducer for use in a relative positioning system.
+This class wraps an Omega pressure transducer.
+Author: Matthew, October 24th, 2013
+Modified: Dan, 2017-10-30
 */
 
 #include "mbed.h"
 
-#define density_of_water_g_cc 1.00  // g/cm^3   (or 1.03 g/cm^3)
+#define water_density_kg_m3 1000    // fresh water density [kg/m^3] (1029 for sea water)
+#define grav_m_s2 9.80665           // gravitational constant [m/s^2]
+
+#define m2ft 3.28084                // convert m to ft
+#define psi2Pa 6894.76              // convert psi to Pa
+
+#define OVERSAMPLE 20               // number of oversamples
 
 class omegaPX209 {
 public:
     omegaPX209(PinName pin);    
-    void initialize();
-    
-    float getPsi();            // returns pressure [psi]
-    float getDepth();          // returns water depth [ft]
-        
+    void init();
+    float tare();                   // tares reading to ambient pressure
+
+    float getPsi();                 // returns pressure [psi]
+    float getDepthFt();             // returns water depth [ft]
+
+    void setZero(float zeroPsi);    // lets user set a different ambient pressure [psi] ... tare, effectively
+    float getZero();                // returns the internal ambient pressure [psi]
+
 private:
-    AnalogIn depthP;
-    Ticker pulse;
-    
-    float P;                    // Pressure [psi]
-    float cal;                  // Volts per psi
-    float multiplier;           // Maximum voltage in (of ADC system)
+    AnalogIn _adc;
+
+    float _psi;                     // pressure [psi]
+    float _zeroPsi;                 // atmospheric pressure at sea level [psi]
+    float _adcVoltage;              // voltage of mbed ADC system [V]
+    float _fullscale;               // maximum pressure of the sensor [psi]
+    float _cal;                     // psi per volt calibration [psi/V]
 };