File content as of revision 101:dbcd3bc51758:

#include <stdio.h>
#include "Potentiometer.h"
#include "SmartRestConf.h"
#include "logging.h"

// Cutoff for avoiding sending similar sensor data.
#define THRESHOLD_PERCENT_ANA 0.02
// Timeout for forcing a sending even if  readings are similar [seconds]
#define TIME_LIMIT_ANA 900

AnalogIn analog1(A0);
AnalogIn analog2(A1);

size_t Potentiometer::read(char *buf, size_t maxLen, char *status, size_t num)
{
        static const char *fmt = "107,%ld,%f,%f\r\n";
        float data[2] = {(float)analog1*100, (float)analog2*100};

        if (abs(oldValues[0]-data[0]) <= abs(oldValues[0])*THRESHOLD_PERCENT_ANA &&
            abs(oldValues[1]-data[1]) <= abs(oldValues[1])*THRESHOLD_PERCENT_ANA) {
                time_t t_interval = time(NULL) - t_start;
                if (t_interval < TIME_LIMIT_ANA) {
                        return 0;
                } else {
                        aDebug("Poti: Timeout at %d s.\n", t_interval);
                }
        }

        size_t l = snprintf(buf, maxLen, fmt, deviceID, data[0], data[1]);
        if (status) {
                snprintf(status, num, "Send Poti %.1f,%.1f", data[0], data[1]);
        }
        oldValues[0] = data[0];
        oldValues[1] = data[1];
        t_start = time(NULL);
        return l;
}