Implemented FCD frequency offset functionality (with re-tune on change).

dsp/rx_source_base.h

@@ -74,6 +74,7 @@ class rx_source_base : public gr_hier_block2
     virtual double get_sample_rate() = 0;
     virtual std::vector<double> get_sample_rates() = 0;
 
+    virtual void set_freq_corr(int ppm) = 0;
     virtual void set_dc_corr(double dci, double dcq) = 0;
     virtual void set_iq_corr(double gain, double phase) = 0;
 };

dsp/rx_source_fcd.cpp

@@ -126,6 +126,13 @@ std::vector<double> rx_source_fcd::get_sample_rates()
     return d_sample_rates;
 }
 
+void rx_source_fcd::set_freq_corr(int ppm)
+{
+    d_fcd_src->set_freq_corr(ppm);
+    // re-tune after frequency correction
+    d_fcd_src->set_freq((float) d_freq);
+}
+
 void rx_source_fcd::set_dc_corr(double dci, double dcq)
 {
     d_fcd_src->set_dc_corr(dci, dcq);

dsp/rx_source_fcd.h

@@ -64,6 +64,7 @@ class rx_source_fcd : public rx_source_base
     double get_sample_rate();
     std::vector<double> get_sample_rates();
 
+    void set_freq_corr(int ppm);
     void set_dc_corr(double dci, double dcq);
     void set_iq_corr(double gain, double phase);
 

mainwindow.cpp

@@ -115,6 +115,7 @@ MainWindow::MainWindow(QWidget *parent) :
     /* connect signals and slots */
     connect(ui->freqCtrl, SIGNAL(NewFrequency(qint64)), this, SLOT(setNewFrequency(qint64)));
     connect(uiDockFcdCtl, SIGNAL(lnaGainChanged(float)), SLOT(setRfGain(float)));
+    connect(uiDockFcdCtl, SIGNAL(freqCorrChanged(int)), this, SLOT(setFreqCorr(int)));
     connect(uiDockFcdCtl, SIGNAL(dcCorrChanged(double,double)), this, SLOT(setDcCorr(double,double)));
     connect(uiDockFcdCtl, SIGNAL(iqCorrChanged(double,double)), this, SLOT(setIqCorr(double,double)));
     connect(uiDockRxOpt, SIGNAL(filterOffsetChanged(qint64)), this, SLOT(setFilterOffset(qint64)));
@@ -306,6 +307,16 @@ void MainWindow::setRfGain(float gain)
     rx->set_rf_gain(gain);
 }
 
+/*! \brief Set new frequency offset value.
+ *  \param ppm Frequency correction.
+ *
+ * The valid range is between -200 and 200, though this is not checked.
+ */
+void MainWindow::setFreqCorr(int ppm)
+{
+    qDebug() << "PPM:" << ppm;
+    rx->set_freq_corr(ppm);
+}
 
 /*! \brief Set new DC offset values.
  *  \param dci I correction.

mainwindow.h

@@ -77,6 +77,7 @@ public slots:
 private slots:
     void setFilterOffset(qint64 freq_hz);
     void setRfGain(float gain);
+    void setFreqCorr(int ppm);
     void setDcCorr(double dci, double dcq);
     void setIqCorr(double gain, double phase);
     void selectDemod(int index);

receiver.cpp

@@ -265,6 +265,14 @@ receiver::status receiver::set_filter_shape(filter_shape shape)
 }
 
 
+receiver::status receiver::set_freq_corr(int ppm)
+{
+    src->set_freq_corr(ppm);
+
+    return STATUS_OK;
+}
+
+
 receiver::status receiver::set_dc_corr(double dci, double dcq)
 {
     src->set_dc_corr(dci, dcq);

receiver.h

@@ -104,6 +104,7 @@ class receiver
     status set_filter_high(double freq_hz);
     status set_filter_shape(filter_shape shape);
 
+    status set_freq_corr(int ppm);
     status set_dc_corr(double dci, double dcq);
     status set_iq_corr(double gain, double phase);