Fix some timing issues resulting from non-integral m_TRperiod for FT4.

Detector.cpp

@@ -55,12 +55,14 @@ void Detector::clear ()
 
 qint64 Detector::writeData (char const * data, qint64 maxSize)
 {
-  int ns=secondInPeriod();
-  if(ns < m_ns) {                      // When ns has wrapped around to zero, restart the buffers
+  static unsigned mstr0=999999;
+  qint64 ms0 = QDateTime::currentMSecsSinceEpoch() % 86400000;
+  unsigned mstr = ms0 % int(1000.0*m_period); // ms into the nominal Tx start time
+  if(mstr < mstr0) {              //When mstr has wrapped around to 0, restart the buffer
     dec_data.params.kin = 0;
     m_bufferPos = 0;
   }
-  m_ns=ns;
+  mstr0=mstr;
 
   // no torn frames
   Q_ASSERT (!(maxSize % static_cast<qint64> (bytesPerFrame ())));
@@ -73,7 +75,7 @@ qint64 Detector::writeData (char const * data, qint64 maxSize)
   if (framesAccepted < static_cast<size_t> (maxSize / bytesPerFrame ())) {
     qDebug () << "dropped " << maxSize / bytesPerFrame () - framesAccepted
                 << " frames of data on the floor!"
-                << dec_data.params.kin << ns;
+                << dec_data.params.kin << mstr;
     }
 
     for (unsigned remaining = framesAccepted; remaining; ) {
@@ -121,14 +123,3 @@ qint64 Detector::writeData (char const * data, qint64 maxSize)
   return maxSize;    // we drop any data past the end of the buffer on
   // the floor until the next period starts
 }
-
-unsigned Detector::secondInPeriod () const
-{
-  // we take the time of the data as the following assuming no latency
-  // delivering it to us (not true but close enough for us)
-  qint64 now (QDateTime::currentMSecsSinceEpoch ());
-
-  unsigned secondInToday ((now % 86400000LL) / 1000);
-  unsigned secInPeriod = fmod(double(secondInToday),m_period);
-  return secInPeriod;
-}

Detector.hpp

@@ -41,7 +41,6 @@ protected:
 
 private:
   void clear ();		// discard buffer contents
-  unsigned secondInPeriod () const;
 
   unsigned m_frameRate;
   double   m_period;

Modulator.cpp

@@ -32,8 +32,8 @@ Modulator::Modulator (unsigned frameRate, double periodLengthInSeconds,
   , m_phi {0.0}
   , m_toneSpacing {0.0}
   , m_fSpread {0.0}
-  , m_frameRate {frameRate}
   , m_period {periodLengthInSeconds}
+  , m_frameRate {frameRate}
   , m_state {Idle}
   , m_tuning {false}
   , m_cwLevel {false}
@@ -50,13 +50,10 @@ void Modulator::start (unsigned symbolsLength, double framesPerSymbol,
   Q_ASSERT (stream);
 // Time according to this computer which becomes our base time
   qint64 ms0 = QDateTime::currentMSecsSinceEpoch() % 86400000;
+  unsigned mstr = ms0 % int(1000.0*m_period); // ms into the nominal Tx start time
 
-//  qDebug() << "ModStart" << QDateTime::currentDateTimeUtc().toString("hh:mm:ss.sss");
-
-  if(m_state != Idle) stop ();
-
+  if(m_state != Idle) stop();
   m_quickClose = false;
-
   m_symbolsLength = symbolsLength;
   m_isym0 = std::numeric_limits<unsigned>::max (); // big number
   m_frequency0 = 0.;
@@ -68,37 +65,33 @@ void Modulator::start (unsigned symbolsLength, double framesPerSymbol,
   m_toneSpacing = toneSpacing;
   m_bFastMode=fastMode;
   m_TRperiod=TRperiod;
-  unsigned delay_ms = 1920 == m_nsps && 15 == m_period ? 500 : 1000;
+  unsigned delay_ms=1000;
+  if(m_nsps==1920) delay_ms=500;   //FT8
+  if(m_nsps==576)  delay_ms=300;   //FT4
 
-  // noise generator parameters
+// noise generator parameters
   if (m_addNoise) {
     m_snr = qPow (10.0, 0.05 * (dBSNR - 6.0));
     m_fac = 3000.0;
     if (m_snr > 1.0) m_fac = 3000.0 / m_snr;
   }
 
-  unsigned mstr = ms0 % int(1000.0*m_period); // ms in period
-
-  // round up to an exact portion of a second that allows for startup
-  // delays
+// round up to an exact portion of a second that allows for startup delays
   m_ic = (mstr / delay_ms) * m_frameRate * delay_ms / 1000;
 
   if(m_bFastMode) m_ic=0;
 
   m_silentFrames = 0;
-  // calculate number of silent frames to send, so that audio will start at
-  // the nominal time "delay_ms" into the Tx sequence.
+// calculate number of silent frames to send, so that audio will start at
+// the nominal time "delay_ms" into the Tx sequence.
   if (synchronize && !m_tuning && !m_bFastMode)	{
     m_silentFrames = m_ic + m_frameRate / (1000 / delay_ms) - (mstr * (m_frameRate / 1000));
   }
-  if(symbolsLength==105 and framesPerSymbol==576
-     and (toneSpacing==12000.0/576.0 or toneSpacing==-2.0)) {
-//### FT4 parameters
-    m_ic=0;
-    m_silentFrames=0;
-  }
-//  qDebug() << "Mod AA" << symbolsLength << framesPerSymbol << toneSpacing;
-//  qDebug() << "Mod AB" << delay_ms << mstr << m_ic << m_silentFrames;
+
+//  qDebug() << "aa" << QDateTime::currentDateTimeUtc().toString("hh:mm:ss.zzz")
+//           << m_ic << m_silentFrames << m_silentFrames/48000.0
+//           << mstr << fmod(double(ms0),1000.0*m_period);
+
 
   initialize (QIODevice::ReadOnly, channel);
   Q_EMIT stateChanged ((m_state = (synchronize && m_silentFrames) ?

widgets/mainwindow.cpp

@@ -2838,12 +2838,12 @@ void MainWindow::decode()                                       //decode()
     dec_data.params.nutc=100*ihr + imin;
     if(m_mode=="ISCAT" or m_mode=="MSK144" or m_bFast9 or m_mode=="FT8" or m_mode=="FT4") {
       qint64 ms=1000.0*(2.0-m_TRperiod);
-      if(m_mode=="FT4") ms=1000.0*(3.0-m_TRperiod);
+      if(m_mode=="FT4") ms=1000.0*(2.0-m_TRperiod);
       QDateTime t=QDateTime::currentDateTimeUtc().addMSecs(ms);
       ihr=t.toString("hh").toInt();
       imin=t.toString("mm").toInt();
       int isec=t.toString("ss").toInt();
-      if(m_mode!="FT4") isec=isec - fmod(double(isec),m_TRperiod);
+      isec=isec - fmod(double(isec),m_TRperiod);
       dec_data.params.nutc=10000*ihr + 100*imin + isec;
     }
   }
@@ -3498,9 +3498,9 @@ void MainWindow::guiUpdate()
   if(m_transmitting or m_auto or m_tune) {
     m_dateTimeLastTX = QDateTime::currentDateTimeUtc ();
 
-// Check for "txboth" (testing purposes only)
+// Check for "txboth" (FT4 testing purposes only)
     QFile f(m_appDir + "/txboth");
-    if(f.exists() and fmod(tsec,m_TRperiod) < (1.0 + 85.0*m_nsps/12000.0)) m_bTxTime=true;
+    if(f.exists() and fmod(tsec,m_TRperiod) < (0.5 + 105.0*576.0/12000.0)) m_bTxTime=true;
 
 // Don't transmit another mode in the 30 m WSPR sub-band
     Frequency onAirFreq = m_freqNominal + ui->TxFreqSpinBox->value();