Diff: WeatherMeters.cpp

Revision:

0:dc42aeff64e6

Child:

1:fa262295fa7e

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WeatherMeters.cpp	Thu Oct 14 11:58:22 2010 +0000
@@ -0,0 +1,109 @@
+/*
+ * mbed library to use a Sparkfun Weather Meters
+ * Copyright (c) 2010 Hiroshi Suga
+ * Released under the MIT License: http://mbed.org/license/mit
+ */
+
+#include "mbed.h"
+#include "WeatherMeters.h"
+
+#define WEATHER_VREF 3.3
+
+const float tbl_windvane[16][2] = {
+  {0.0, 33000}, {22.5, 6570}, {45.0, 8200}, {67.5, 891},
+  {90.0, 1000}, {112.5, 688}, {135.0, 2200}, {157.5, 1410},
+  {180.0, 3900}, {202.5, 3140}, {225.0, 16000}, {247.5, 14120},
+  {270.0, 120000}, {292.5, 42120}, {315.0, 64900}, {337.5, 21880} 
+};
+
+WeatherMeters::WeatherMeters (PinName p_anemometer, PinName p_windvane, PinName p_raingauge, Weather_mode w_mode) : int01(p_anemometer), int02(p_raingauge), ain01(p_windvane) {
+    int i;
+
+    windspeed = 0; windvane = 0; raingauge = 0;
+    count_anemo = 0; count_rain = 0; time_anemo = 0; time_rain = 0;
+    for (i = 0; i < 12; i ++) {
+        buf_anemo[i] = 0;
+        buf_rain[i] = 0;
+    }
+
+    mode = w_mode;
+    int01.fall(this, &WeatherMeters::int_anemometer);
+    int02.fall(this, &WeatherMeters::int_raingauge);
+    ticker01.attach(this, &WeatherMeters::int_timer, 0.25); 
+}
+
+float WeatherMeters::get_windspeed() {
+    float s;
+    
+    if (mode == Weather_auto) { 
+        s = (float)windspeed * 0.667 / 3.0; // 0.667m/s/Hz (/3s)
+        windspeed = 0;
+    } else {
+        s = (float)count_anemo * 0.667 / ((float)time_anemo / 4.0); // 0.667m/s/Hz
+        time_anemo = 0;
+        count_anemo = 0;
+    }
+    return s;
+}
+
+float WeatherMeters::get_windvane() {
+    int i;
+    float v;
+
+    if (windspeed == 0) windvane = ain01;
+    v = windvane * WEATHER_VREF; // V
+    v = v / ((WEATHER_VREF - v) / 10000.0); // ohm
+    for (i = 0; i < 16; i ++) {
+        if (v > tbl_windvane[i][1] * 0.9 && v < tbl_windvane[i][1] * 1.1) {
+            return tbl_windvane[i][0];
+        }
+    }
+    return 0;
+}
+
+float WeatherMeters::get_raingauge() {
+    return (float)raingauge * 0.2794; // 0.2794mm/Hz
+}
+
+void WeatherMeters::int_anemometer () {
+    count_anemo ++;
+}
+
+void WeatherMeters::int_raingauge () {
+    count_rain ++;
+}
+
+void WeatherMeters::int_timer () {
+    int i, n;
+    
+    if (mode == Weather_auto) {
+        n = 0;
+        for (i = 11; i > 0; i --) {
+            buf_anemo[i] = buf_anemo[i - 1];
+            n = n + buf_anemo[i];
+        }
+        buf_anemo[0] = count_anemo;
+        n = n + buf_anemo[0];
+        count_anemo = 0;
+        if (n > windspeed) {
+            windspeed = n;
+            windvane = ain01;
+        }
+    } else {
+        time_anemo ++;
+    }
+    
+    time_rain ++;
+    if (time_rain >= 4 * 300) {
+        n = 0;
+        for (i = 11; i > 0; i --) {
+            buf_rain[i] = buf_rain[i - 1];
+            n = n + buf_rain[i];
+        }
+        buf_rain[0] = count_rain;
+        n = n + buf_rain[0];
+        count_rain = 0;
+        time_rain = 0;
+        raingauge = n;
+    }
+}