Diff: BME280.cpp

Revision:

7:d94871acb463

Parent:

6:f94ffb546799

Child:

8:4c37112d31cf

--- a/BME280.cpp	Sat Dec 29 05:49:55 2018 +0000
+++ b/BME280.cpp	Tue Jan 15 10:06:32 2019 +0000
@@ -32,8 +32,8 @@
  *
  *  http://www.page.sannet.ne.jp/kenjia/index.html
  *  http://mbed.org/users/kenjiArai/
- *      Created:    November  21st, 2018
- *      Revised:    December  29th, 2018
+ *      Started:    November  21st, 2018
+ *      Revised:    January    5th, 2019
  */
 
 #include "mbed.h"
@@ -345,7 +345,26 @@
 void BME280::getAll_compensated_data(BME280_Data_TypeDef *dt) { 
     uint32_t raw_data;
     char cmd[8];
- 
+
+    // Humidity
+    cmd[0] = 0xfd; // hum_msb
+    i2c.write(address, cmd, 1);
+    i2c.read(address, &cmd[1], 2);
+    raw_data = (cmd[1] << 8) | cmd[2];
+    double var_H;
+    var_H = (((double)t_fine) - 76800.0);
+    var_H = (raw_data - (((double)dig_H4) * 64.0 + 
+            ((double)dig_H5) / 16384.0 * var_H)) *
+            (((double)dig_H2) / 65536.0 * (1.0 + 
+            ((double)dig_H6) / 67108864.0 * var_H * 
+            (1.0 + ((double)dig_H3) / 67108864.0 * var_H)));
+    var_H = var_H * (1.0 - ((double)dig_H1) * var_H / 524288.0);
+    if (var_H > 100.0) {
+        var_H = 100.0;
+    } else if (var_H < 0.0) {
+        var_H = 0.0;
+    }
+    dt->humidity = var_H;
     // Temperatue
     cmd[0] = 0xfa; // temp_msb
     i2c.write(address, cmd, 1);
@@ -382,26 +401,49 @@
     var2 = p * ((double)dig_P8) / 32768.0;
     p = p + (var1 + var2 + ((double)dig_P7)) / 16.0;
     dt->pressue = p / 100.0;
-    // Humidity
-    cmd[0] = 0xfd; // hum_msb
+}
+
+void BME280::frequency(int hz)
+{
+    i2c.frequency(hz);
+}
+
+#if 0
+double BME280::calcAltitude_relative(double ref_press)
+{
+    double x1, x2;
+    uint32_t raw_data;
+    char cmd[8];
+#if 0
+    // Pressue
+    cmd[0] = 0xf7; // press_msb
     i2c.write(address, cmd, 1);
-    i2c.read(address, &cmd[1], 2);
-    raw_data = (cmd[1] << 8) | cmd[2];
-    double var_H;
-    var_H = (((double)t_fine) - 76800.0);
-    var_H = (raw_data - (((double)dig_H4) * 64.0 + 
-            ((double)dig_H5) / 16384.0 * var_H)) *
-            (((double)dig_H2) / 65536.0 * (1.0 + 
-            ((double)dig_H6) / 67108864.0 * var_H * 
-            (1.0 + ((double)dig_H3) / 67108864.0 * var_H)));
-    var_H = var_H * (1.0 - ((double)dig_H1) * var_H / 524288.0);
-    if (var_H > 100.0) {
-        var_H = 100.0;
-    } else if (var_H < 0.0) {
-        var_H = 0.0;
-    }
-    dt->humidity = var_H;
+    i2c.read(address, &cmd[1], 3);
+    raw_data = (cmd[1] << 12) | (cmd[2] << 4) | (cmd[3] >> 4);
+    x2 = 1.0 / 5.2553026;
+    x1 = pow((ref_press / (double)raw_data), x2) - 1.0;
+    // Temperatue
+    cmd[0] = 0xfa; // temp_msb
+    i2c.write(address, cmd, 1);
+    i2c.read(address, &cmd[1], 3);
+    raw_data = (cmd[1] << 12) | (cmd[2] << 4) | (cmd[3] >> 4);
+    x2 = x1 * ((double)raw_data + 273.15) / 0.0065;
+    return x2;
+#else
+    cmd[0] = 0xf7; // press_msb
+    i2c.write(address, cmd, 1);
+    i2c.read(address, &cmd[1], 3);
+    raw_data = (cmd[1] << 12) | (cmd[2] << 4) | (cmd[3] >> 4);
+    x1 = pow(((double)raw_data / ref_press), 0.190294957);
+    x2 = 44330.0 * (1.0 - x1);
+    return x2;
+    /*
+    double altitude =
+     44330.0 * (1.0 - pow(pressure / MEAN_SEA_LEVEL_PRESSURE, 0.190294957));
+    */
+#endif
 }
+#endif
 
 #if 0
 double calcAltitude(float pressure,float temperature) 
@@ -421,4 +463,4 @@
         44330.0 * (1.0 - pow(pressure / MEAN_SEA_LEVEL_PRESSURE, 0.190294957)); 
     return altitude; 
 }
-#endif
\ No newline at end of file
+#endif