Diff: MS5607Base.h

Revision:

1:b7fffbf481e2

Parent:

0:5760862143d1

--- a/MS5607Base.h	Tue Jul 03 08:57:57 2012 +0000
+++ b/MS5607Base.h	Wed Dec 25 15:12:21 2019 +0000
@@ -25,6 +25,18 @@
 
 class MS5607Base {
 public:
+    void init(float itemp=0,float ipress=0) {
+        writeCommand(RESET, 3);
+        c1 = readPROM(1);
+        c2 = readPROM(2);
+        c3 = readPROM(3);
+        c4 = readPROM(4);
+        c5 = readPROM(5);
+        c6 = readPROM(6);
+        inittemp = itemp;
+        initpress= ipress;
+    }
+    
     void printCoefficients() {
         printf("%d, %d, %d, %d, %d, %d\n", c1, c2, c3, c4, c5, c6);
     }
@@ -38,12 +50,12 @@
     }
 
     float getTemperature() {
-        int dT = getRawTemperature() - (c5 << 8);
-        int temp = 2000 + ((dT * c6) >> 23);
+        int dT = getRawTemperature() - ((0x0FFFF&c5) << 8);
+        int temp = 2000 + (((int64_t)dT * (0x0FFFF&c6)) >> 23);
         
         // 2nd order temperature compensation
         if (temp < 2000) {
-            int t2 = (int64_t) dT * dT >> 31;
+            int t2 = ((int64_t) dT * dT )>> 31;
             temp -= t2;
         }
 
@@ -77,7 +89,7 @@
 
 protected:
     int32_t c1, c2, c3, c4, c5, c6;
-
+    float inittemp, initpress;
     enum {
         RESET     = 0x1E,
         ADC_READ  = 0x00,
@@ -96,23 +108,17 @@
     virtual int readPROM(int address) = 0;
     virtual int readADC(int command) = 0;
 
-    void init() {
-        writeCommand(RESET, 3);
-        c1 = readPROM(1);
-        c2 = readPROM(2);
-        c3 = readPROM(3);
-        c4 = readPROM(4);
-        c5 = readPROM(5);
-        c6 = readPROM(6);
-    }
+
 
     float toAltitude(int pressure) {
         // Ref. 29124-AltimeterAppNote1.pdf
         const float R = 287.052; // specific gas constant R*/M0
         const float g = 9.80665; // standard gravity 
         const float t_grad = 0.0065; // gradient of temperature
-        const float t0 = 273.15 + 15; // temperature at 0 altitude
-        const float p0 = 101325; // pressure at 0 altitude
+        if(inittemp==0) inittemp=15;
+        if(initpress==0) initpress=101325;
+        float t0 = 273.15 + inittemp; // temperature at 0 altitude
+        float p0 = initpress;// 101700; // pressure at 0 altitude
 
         return t0 / t_grad * (1 - exp((t_grad * R / g) * log(pressure / p0)));
     }