File content as of revision 96:5dfdc8568e9f:

#include "SignalQualityMeasurement.h"
#include "ComposedRecord.h"
#include "CharValue.h"
#include "IntegerValue.h"
#include "FloatValue.h"
#include "LCDDisplay.h"
#include "logging.h"

#define THRESHOLD_PERCENT_SIG 0.06       // Percentage cut-off for avoiding sending similar signal sensor data.
// Time interval for forcing a sending even if analog sensor readings are constantly similar (in seconds).
#define TIME_LIMIT_SIG 900               

SignalQualityMeasurement::SignalQualityMeasurement(AbstractSmartRest& client, 
    SmartRestTemplate& tpl, long& deviceId, DeviceInfo& deviceInfo) :
    _deviceId(deviceId),
    _tpl(tpl),
    _client(client),
    _deviceInfo(deviceInfo)
{
    _init = false;
    oldValues[0] = 0;
    oldValues[1] = 0;
    t_start = time(NULL);
}

bool SignalQualityMeasurement::init()
{
    if (_init)
        return false;
    
    // Insert measurement
    // USAGE: 104,<DEVICE/ID>,<RSSI>,<BER>
    if (!_tpl.add("10,104,POST,/measurement/measurements,application/vnd.com.nsn.cumulocity.measurement+json,application/vnd.com.nsn.cumulocity.measurement+json,%%,NOW UNSIGNED NUMBER UNSIGNED,\"{\"\"time\"\":\"\"%%\"\",\"\"source\"\":{\"\"id\"\":\"\"%%\"\"},\"\"type\"\":\"\"c8y_SignalStrength\"\",\"\"c8y_SignalStrength\"\":{\"\"rssi\"\":{\"\"value\"\":%%,\"\"unit\"\":\"\"dBm\"\"},\"\"ber\"\":{\"\"value\"\":%%,\"\"unit\"\":\"\"%\"\"}}}\"\r\n"))
        return false;

    _init = true;
    return true;
}

bool SignalQualityMeasurement::run()
{
    static char signal[25] = {0};
    DeviceInfo::SignalQuality *signalQuality;
    if ((signalQuality = _deviceInfo.signalQuality()) == NULL)
        return false;
    if (signalQuality && signalQuality->rssi)
        snprintf(signal, sizeof(signal), "Network: %d dBm", signalQuality->rssi);
    else
        strncpy(signal, "Network: no coverage", sizeof(signal));
    if (strcmp(LCDDisplay::inst().getSecondLine(), signal)) {
        LCDDisplay::inst().setSecondLine(signal);
    }

    int data[2] = {signalQuality->rssi, signalQuality->ber};
    if (abs(oldValues[0]-data[0]) <= abs(oldValues[0])*THRESHOLD_PERCENT_SIG &&
        abs(oldValues[1]-data[1]) <= abs(oldValues[1])*THRESHOLD_PERCENT_SIG) {
        time_t t_interval = time(NULL) - t_start;
        if (t_interval < TIME_LIMIT_SIG) {
            if (strcmp(LCDDisplay::inst().getThirdLine(), "")) {
                LCDDisplay::inst().setThirdLine("");
            }
            return true;
        } else {
            aDebug("Signal: Timeout at %d s.\n", t_interval);
        }
    }

    char status[25] = {0};
    snprintf(status, 25, "Send dBm %d,%d", data[0], data[1]);
    LCDDisplay::inst().setThirdLine(status);
    ComposedRecord record;
    IntegerValue msgId(104);
    IntegerValue devId(_deviceId);
    IntegerValue rssi(signalQuality->rssi);
    IntegerValue ber(signalQuality->ber);
    if ((!record.add(msgId)) || (!record.add(devId)) || (!record.add(rssi)) || (!record.add(ber)))
        return false;

    time_t t0 = time(NULL);
    if (_client.send(record) != SMARTREST_SUCCESS) {
        aWarning("Signal: Send failed.\n");
        _client.stop();
        return false;
    }
    time_t t1 = time(NULL);
    _client.stop();
    aDebug("Signal: Sent in %d s.\n", t1-t0);
    oldValues[0] = data[0];
    oldValues[1] = data[1];
    t_start = time(NULL);
    return true;
}