Diff: measurement/Acceleration.cpp

Revision:

101:dbcd3bc51758

Child:

115:c54e9731b9de

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/measurement/Acceleration.cpp	Fri May 08 12:19:57 2015 +0000
@@ -0,0 +1,39 @@
+#include <stdio.h>
+#include "SmartRestConf.h"
+#include "Acceleration.h"
+#include "logging.h"
+
+// Percentage cut-off for avoiding sending similar sensor reading.
+#define THRESHOLD_PERCENT_ACCE 0.1
+// Timeout for forcing a sending even if readings are similar [seconds].
+#define TIME_LIMIT_ACCE 900
+
+size_t Acceleration::read(char *buf, size_t maxLen, char *status, size_t num)
+{
+        static const char *fmt = "106,%ld,%f,%f,%f\r\n";
+        if (!deviceReady)
+                return 0;
+        float data[3] = { 0.0, 0.0, 0.0 };
+        sensor.readData(data);
+
+        if ((0.15 > abs(data[0]) || abs(oldValues[0]-data[0]) <= abs(oldValues[0])*THRESHOLD_PERCENT_ACCE) &&
+            (0.10 > abs(data[1]) || abs(oldValues[1]-data[1]) <= abs(oldValues[1])*THRESHOLD_PERCENT_ACCE)) {
+                time_t t_interval = time(NULL) - t_start;
+                if (t_interval < TIME_LIMIT_ACCE) {
+                        return 0;
+                } else {
+                        aDebug("Acc: Timeout at %d s.\n", t_interval);
+                }
+        }
+
+        size_t l = snprintf(buf, maxLen, fmt, deviceID, data[0], data[1], data[2]);
+        if (status) {
+                snprintf(status, num, "Send Acc %.1f,%.1f,%.1f",
+                         data[0], data[1], data[2]);
+        }
+        oldValues[0] = data[0];
+        oldValues[1] = data[1];
+        oldValues[2] = data[2];
+        t_start = time(NULL);
+        return l;
+}
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