Acceleration.cpp

00001 #include <stdio.h>
00002 #include "rtos.h"
00003 #include "SmartRestConf.h"
00004 #include "Acceleration.h"
00005 #include "logging.h"
00006 
00007 // Percentage cut-off for avoiding sending similar sensor reading.
00008 #define THRESHOLD_PERCENT_ACCE 0.1
00009 // Timeout for forcing a sending even if readings are similar [seconds].
00010 #define TIME_LIMIT_ACCE 900
00011 
00012 static inline bool valueChanged(float *V0, float *V1)
00013 {
00014 //        if (abs(oldValues[0]-data[0]) <= abs(oldValues[0])*THRESHOLD_PERCENT_ACCE ||
00015 //            abs(oldValues[1]-data[1]) <= abs(oldValues[1])*THRESHOLD_PERCENT_ACCE ||
00016 //            abs(oldValues[2]-data[2]) <= abs(oldValues[2])*THRESHOLD_PERCENT_ACCE) {
00017         if ((0.15 > abs(V1[0]) || abs(V0[0]-V1[0]) <= abs(V0[0])*THRESHOLD_PERCENT_ACCE) &&
00018             (0.10 > abs(V1[1]) || abs(V0[1]-V1[1]) <= abs(V0[1])*THRESHOLD_PERCENT_ACCE))
00019                 return false;
00020         else
00021                 return true;
00022 }
00023 
00024 int Acceleration::read(char *buf, size_t maxLen, char *status, size_t num)
00025 {
00026         static const char *fmt = "106,%ld,%f,%f,%f\r\n";
00027         if (!deviceReady)
00028                 return 0;
00029         float data[3] = {0.0, 0.0, 0.0};
00030 //        float min[3] = {100, 100, 100};
00031 //        float max[3] = {0, 0, 0};
00032 //        const unsigned short N = 10;
00033 //        for (unsigned short i = 0; i < N; ++i) {
00034 //                float d[3] = {0, 0, 0};
00035 //                sensor.readData(d);
00036 //                for (unsigned short j = 0; j < 3; ++j) {
00037 //                        data[j] += d[j];
00038 //                        if (d[j] < min[j]) min[j] = d[j];
00039 //                        if (d[j] > max[j]) max[j] = d[j];
00040 //                }
00041 //                Thread::wait(5);
00042 //        }
00043 //        data[0] = (data[0]-min[0]-max[0]) / (N-2);
00044 //        data[1] = (data[1]-min[1]-max[1]) / (N-2);
00045 //        data[2] = (data[2]-min[2]-max[2]) / (N-2);
00046         sensor.readData(data);
00047         float t_interval = timer.read();
00048         if (!valueChanged(oldValues, data) && t_interval < TIME_LIMIT_ACCE) {
00049                 return 0;
00050         }
00051 
00052         size_t l = snprintf(buf, maxLen, fmt, deviceID, data[0], data[1], data[2]);
00053         if (status) {
00054                 snprintf(status, num, "Send Acc %.1f,%.1f,%.1f",
00055                          data[0], data[1], data[2]);
00056         }
00057         oldValues[0] = data[0];
00058         oldValues[1] = data[1];
00059         oldValues[2] = data[2];
00060         timer.reset();
00061         return l;
00062 }