From 31fb81c66af78c1a5c9f317cbabe66316cc964c7 Mon Sep 17 00:00:00 2001
From: f4exb <f4exb06@gmail.com>
Date: Sat, 9 May 2015 00:54:01 +0200
Subject: [PATCH] Implemented rtl-sdr ppm LO correction

---
 plugins/samplesource/rtlsdr/rtlsdrgui.cpp   |  9 ++++
 plugins/samplesource/rtlsdr/rtlsdrgui.h     |  1 +
 plugins/samplesource/rtlsdr/rtlsdrgui.ui    | 51 ++++++++++++++++++++-
 plugins/samplesource/rtlsdr/rtlsdrinput.cpp | 14 ++++++
 plugins/samplesource/rtlsdr/rtlsdrinput.h   |  1 +
 5 files changed, 74 insertions(+), 2 deletions(-)

diff --git a/plugins/samplesource/rtlsdr/rtlsdrgui.cpp b/plugins/samplesource/rtlsdr/rtlsdrgui.cpp
index d254eb016..5fd10cf60 100644
--- a/plugins/samplesource/rtlsdr/rtlsdrgui.cpp
+++ b/plugins/samplesource/rtlsdr/rtlsdrgui.cpp
@@ -129,6 +129,15 @@ void RTLSDRGui::on_centerFrequency_changed(quint64 value)
 	sendSettings();
 }
 
+void RTLSDRGui::on_ppm_valueChanged(int value)
+{
+	if((value > 99) || (value < -99))
+		return;
+	ui->ppmText->setText(tr("%1").arg(value));
+	m_settings.m_loPpmCorrection = value;
+	sendSettings();
+}
+
 void RTLSDRGui::on_gain_valueChanged(int value)
 {
 	if(value > (int)m_gains.size())
diff --git a/plugins/samplesource/rtlsdr/rtlsdrgui.h b/plugins/samplesource/rtlsdr/rtlsdrgui.h
index c5031dba0..5fe3ee225 100644
--- a/plugins/samplesource/rtlsdr/rtlsdrgui.h
+++ b/plugins/samplesource/rtlsdr/rtlsdrgui.h
@@ -44,6 +44,7 @@ private:
 
 private slots:
 	void on_centerFrequency_changed(quint64 value);
+	void on_ppm_valueChanged(int value);
 	void on_gain_valueChanged(int value);
 	void on_samplerate_valueChanged(int value);
 	void on_checkBox_stateChanged(int state);
diff --git a/plugins/samplesource/rtlsdr/rtlsdrgui.ui b/plugins/samplesource/rtlsdr/rtlsdrgui.ui
index a363e470b..182db9797 100644
--- a/plugins/samplesource/rtlsdr/rtlsdrgui.ui
+++ b/plugins/samplesource/rtlsdr/rtlsdrgui.ui
@@ -6,8 +6,8 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>132</width>
-    <height>119</height>
+    <width>198</width>
+    <height>155</height>
    </rect>
   </property>
   <property name="sizePolicy">
@@ -214,6 +214,53 @@
      </item>
     </layout>
    </item>
+   <item>
+    <widget class="Line" name="line_2">
+     <property name="orientation">
+      <enum>Qt::Horizontal</enum>
+     </property>
+    </widget>
+   </item>
+   <item>
+    <layout class="QGridLayout" name="gridLayout_1">
+     <property name="spacing">
+      <number>3</number>
+     </property>
+     <item row="0" column="1">
+      <widget class="QSlider" name="ppm">
+       <property name="minimum">
+        <number>-99</number>
+       </property>
+       <property name="orientation">
+        <enum>Qt::Horizontal</enum>
+       </property>
+      </widget>
+     </item>
+     <item row="0" column="2">
+      <widget class="QLabel" name="ppmText">
+       <property name="minimumSize">
+        <size>
+         <width>40</width>
+         <height>0</height>
+        </size>
+       </property>
+       <property name="text">
+        <string>0</string>
+       </property>
+       <property name="alignment">
+        <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+       </property>
+      </widget>
+     </item>
+     <item row="0" column="0">
+      <widget class="QLabel" name="label_10">
+       <property name="text">
+        <string>ppm</string>
+       </property>
+      </widget>
+     </item>
+    </layout>
+   </item>
    <item>
     <widget class="Line" name="line">
      <property name="orientation">
diff --git a/plugins/samplesource/rtlsdr/rtlsdrinput.cpp b/plugins/samplesource/rtlsdr/rtlsdrinput.cpp
index f27a0844c..a1d6f1a71 100644
--- a/plugins/samplesource/rtlsdr/rtlsdrinput.cpp
+++ b/plugins/samplesource/rtlsdr/rtlsdrinput.cpp
@@ -35,6 +35,7 @@ void RTLSDRInput::Settings::resetToDefaults()
 {
 	m_gain = 0;
 	m_samplerate = 1024000;
+	m_loPpmCorrection = 0;
 }
 
 QByteArray RTLSDRInput::Settings::serialize() const
@@ -42,6 +43,7 @@ QByteArray RTLSDRInput::Settings::serialize() const
 	SimpleSerializer s(1);
 	s.writeS32(1, m_gain);
 	s.writeS32(2, m_samplerate);
+	s.writeS32(3, m_loPpmCorrection);
 	return s.final();
 }
 
@@ -57,6 +59,7 @@ bool RTLSDRInput::Settings::deserialize(const QByteArray& data)
 	if(d.getVersion() == 1) {
 		d.readS32(1, &m_gain, 0);
 		//d.readS32(2, &m_samplerate, 0);
+		d.readS32(3, &m_loPpmCorrection, 0);
 		return true;
 	} else {
 		resetToDefaults();
@@ -231,6 +234,17 @@ bool RTLSDRInput::applySettings(const GeneralSettings& generalSettings, const Se
 		}
 	}
 
+	if((m_settings.m_loPpmCorrection != settings.m_loPpmCorrection) || force) {
+		if(m_dev != NULL) {
+			if( rtlsdr_set_freq_correction(m_dev, settings.m_loPpmCorrection) < 0)
+				qCritical("could not set LO ppm correction: %d", settings.m_loPpmCorrection);
+			else {
+				m_settings.m_loPpmCorrection = settings.m_loPpmCorrection;
+				//m_rtlSDRThread->setSamplerate(settings.m_samplerate);
+			}
+		}
+	}
+
 	m_generalSettings.m_centerFrequency = generalSettings.m_centerFrequency;
 	if(m_dev != NULL) {
 		if(rtlsdr_set_center_freq( m_dev, m_generalSettings.m_centerFrequency
diff --git a/plugins/samplesource/rtlsdr/rtlsdrinput.h b/plugins/samplesource/rtlsdr/rtlsdrinput.h
index 34dfb71a0..f3fdbc64e 100644
--- a/plugins/samplesource/rtlsdr/rtlsdrinput.h
+++ b/plugins/samplesource/rtlsdr/rtlsdrinput.h
@@ -29,6 +29,7 @@ public:
 	struct Settings {
 		qint32 m_gain;
 		qint32 m_samplerate;
+		qint32 m_loPpmCorrection;
 
 		Settings();
 		void resetToDefaults();