Basic receiver that can actually receive NFM.

mainwindow.cc

@@ -17,6 +17,7 @@
  * the Free Software Foundation, Inc., 51 Franklin Street,
  * Boston, MA 02110-1301, USA.
  */
+#include <QDebug>
 #include "mainwindow.h"
 #include "ui_mainwindow.h"
 
@@ -25,9 +26,31 @@ MainWindow::MainWindow(QWidget *parent) :
     ui(new Ui::MainWindow)
 {
     ui->setupUi(this);
+
+    /* create receiver object */
+    rx = new receiver("hw:1");
+
+    rx->set_rf_freq(144500000.0f);
+    rx->set_filter_offset(25000.0);
 }
 
 MainWindow::~MainWindow()
 {
     delete ui;
+    delete rx;
+}
+
+
+void MainWindow::on_rxStartStopButton_toggled(bool checked)
+{
+    if (checked) {
+        /* start receiver and update button label */
+        rx->start();
+        ui->rxStartStopButton->setText(tr("Stop"));
+    }
+    else {
+        /* stop receiver and update label */
+        rx->stop();
+        ui->rxStartStopButton->setText(tr("Start"));
+    }
 }

mainwindow.h

@@ -21,6 +21,8 @@
 #define MAINWINDOW_H
 
 #include <QMainWindow>
+#include <receiver.h>
+
 
 namespace Ui {
     class MainWindow;
@@ -36,6 +38,11 @@ class MainWindow : public QMainWindow
 
 private:
     Ui::MainWindow *ui;
+
+    receiver *rx;
+
+private slots:
+    void on_rxStartStopButton_toggled(bool checked);  /*! RX start/stop button toggled. */
 };
 
 #endif // MAINWINDOW_H

mainwindow.ui

@@ -1,24 +1,57 @@
+<?xml version="1.0" encoding="UTF-8"?>
 <ui version="4.0">
  <class>MainWindow</class>
- <widget class="QMainWindow" name="MainWindow" >
-  <property name="geometry" >
+ <widget class="QMainWindow" name="MainWindow">
+  <property name="geometry">
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>400</width>
-    <height>300</height>
+    <width>461</width>
+    <height>309</height>
    </rect>
   </property>
-  <property name="windowTitle" >
+  <property name="windowTitle">
    <string>MainWindow</string>
   </property>
-  <widget class="QMenuBar" name="menuBar" />
-  <widget class="QToolBar" name="mainToolBar" />
-  <widget class="QWidget" name="centralWidget" />
-  <widget class="QStatusBar" name="statusBar" />
+  <widget class="QWidget" name="centralWidget">
+   <widget class="QPushButton" name="rxStartStopButton">
+    <property name="geometry">
+     <rect>
+      <x>20</x>
+      <y>210</y>
+      <width>98</width>
+      <height>27</height>
+     </rect>
+    </property>
+    <property name="text">
+     <string>Start</string>
+    </property>
+    <property name="checkable">
+     <bool>true</bool>
+    </property>
+   </widget>
+  </widget>
+  <widget class="QMenuBar" name="menuBar">
+   <property name="geometry">
+    <rect>
+     <x>0</x>
+     <y>0</y>
+     <width>461</width>
+     <height>25</height>
+    </rect>
+   </property>
+  </widget>
+  <widget class="QToolBar" name="mainToolBar">
+   <attribute name="toolBarArea">
+    <enum>TopToolBarArea</enum>
+   </attribute>
+   <attribute name="toolBarBreak">
+    <bool>false</bool>
+   </attribute>
+  </widget>
+  <widget class="QStatusBar" name="statusBar"/>
  </widget>
- <layoutDefault spacing="6" margin="11" />
- <pixmapfunction></pixmapfunction>
+ <layoutdefault spacing="6" margin="11"/>
  <resources/>
  <connections/>
 </ui>

receiver.cc

@@ -26,17 +26,22 @@ receiver::receiver(const std::string input_device, const std::string audio_devic
     tb = gr_make_top_block("gqrx");
 
     fcd_src = fcd_make_source_c(input_device);
+    fcd_src->set_freq(144500000.0f);
+    filter = make_rx_filter(d_bandwidth, 0.0, -5000.0, 5000.0, 1000.0);
+    demod_fm = make_rx_demod_fm(48000.0, 48000.0, 5000.0, 50.0e-6);
 
     audio_snk = audio_make_sink(d_audio_rate, audio_device, true);
 
-    tb->connect(fcd_src, 0, audio_snk, 0);
+    tb->connect(fcd_src, 0, filter, 0);
+    tb->connect(filter, 0, demod_fm, 0);
+    tb->connect(demod_fm, 0, audio_snk, 0);
 
 }
 
 receiver::~receiver()
 {
     tb->stop();
-    tb->wait();
+
 
     /* FIXME: delete blocks? */
 }
@@ -51,11 +56,14 @@ void receiver::start()
 void receiver::stop()
 {
     tb->stop();
+    tb->wait(); // If the graph is needed to run again, wait() must be called after stop
+    // FIXME: aUaO
 }
 
 
 receiver::status receiver::set_rf_freq(float freq_hz)
 {
+    fcd_src->set_freq(freq_hz);
     return STATUS_OK;
 }
 

receiver.h

@@ -23,6 +23,8 @@
 #include <gr_top_block.h>
 #include <gr_audio_sink.h>
 #include <fcd/fcd_source_c.h>
+#include <rx_filter.h>
+#include <rx_demod_fm.h>
 
 
 /*! \defgroup DSP Digital signal processing library based on GNU Radio */
@@ -126,6 +128,8 @@ class receiver
 
     gr_top_block_sptr tb;        /*! The GNU Radio top block. */
     fcd_source_c_sptr fcd_src;   /*! Funcube Dongle source. */
+    rx_filter_sptr    filter;
+    rx_demod_fm_sptr  demod_fm;
 
     audio_sink::sptr audio_snk; /*! Audio sink. */