Tx ph.1: fixed read pointer management when getting new samples

Readme.md

@@ -27,6 +27,16 @@ These plugins come from the parent code base and have been maintained so that th
 
 From version 2 SDRangel can integrate more than one hardware device running concurrently.
 
+<h2>Transmission support</h2>
+
+Transmission or signal generation support for eligible devices (BladeRF and HackRF) will be progressively introduced with the following roadmap:
+
+  - Phase 1: version 2.2.0: generation to file (File Sink) with AM modulator with simple sine modulation. Fixed sample rate of 48 kS/s (no interpolation)
+  - Phase 2: version 2.2.x: full baseband interpolation chain: in AM modulator and Up Channelizer.
+  - Phase 3: version 2.3.0: FM and SSB modulators with audio file input
+  - Phase 4: version 2.3.x: Audio (Mic) input support
+  - phase 5: version 3.0.0: BladeRF and HackRF support including final interpolation stage.
+
 <h2>Airspy</h2>
 
 Airspy is supported through the libairspy library that should be installed in your system for proper build of the software and operation support. Add `libairspy-dev` to the list of dependencies to install.

plugins/samplesink/filesink/filesinkthread.cpp

@@ -26,7 +26,6 @@ FileSinkThread::FileSinkThread(std::ofstream *samplesStream, SampleSourceFifo* s
 	QThread(parent),
 	m_running(false),
 	m_ofstream(samplesStream),
-	m_buf(0),
 	m_bufsize(0),
 	m_samplesChunkSize(0),
 	m_sampleFifo(sampleFifo),
@@ -43,10 +42,6 @@ FileSinkThread::~FileSinkThread()
 	if (m_running) {
 		stopWork();
 	}
-
-	if (m_buf != 0) {
-		free(m_buf);
-	}
 }
 
 void FileSinkThread::startWork()
@@ -132,10 +127,11 @@ void FileSinkThread::tick()
             m_throttleToggle = !m_throttleToggle;
         }
 
-        SampleVector::iterator beginRead;
+        SampleVector::iterator readUntil;
 
-        m_sampleFifo->readAndSignal(beginRead, m_samplesChunkSize);
-        m_ofstream->write(reinterpret_cast<char*>(&(*beginRead)), m_samplesChunkSize*4);
+        m_sampleFifo->readAdvance(readUntil, m_samplesChunkSize);
+        SampleVector::iterator beginRead = readUntil - m_samplesChunkSize;
+        m_ofstream->write(reinterpret_cast<char*>(&(*beginRead)), m_samplesChunkSize*sizeof(Sample));
         m_samplesCount += m_samplesChunkSize;
 	}
 }

plugins/samplesink/filesink/filesinkthread.h

@@ -55,7 +55,6 @@ private:
 	bool m_running;
 
 	std::ofstream* m_ofstream;
-	quint8  *m_buf;
 	std::size_t m_bufsize;
 	unsigned int m_samplesChunkSize;
 	SampleSourceFifo* m_sampleFifo;

sdrbase/dsp/samplesourcefifo.cpp

@@ -50,15 +50,13 @@ void SampleSourceFifo::init()
     m_init = true;
 }
 
-void SampleSourceFifo::readAndSignal(SampleVector::iterator& beginRead, unsigned int nbSamples)
+void SampleSourceFifo::readAdvance(SampleVector::iterator& readUntil, unsigned int nbSamples)
 {
     QMutexLocker mutexLocker(&m_mutex);
-
     assert(nbSamples < m_samplesChunkSize/2);
 
-    beginRead = m_data.begin() + m_size + m_ir;
     m_ir = (m_ir + nbSamples) % m_size;
-
+    readUntil =  m_data.begin() + m_size + m_ir;
     emit dataRead(nbSamples);
 
     int i_delta = m_iw - m_ir;

sdrbase/dsp/samplesourcefifo.h

@@ -35,10 +35,10 @@ public:
 
     void resize(uint32_t size, uint32_t samplesChunkSize);
     void init();
-    /** begin read at current read point for the given length and activate R/W signals */
-    void readAndSignal(SampleVector::iterator& beginRead, unsigned int nbSamples);
+    /** advance read pointer for the given length and activate R/W signals */
+    void readAdvance(SampleVector::iterator& readUntil, unsigned int nbSamples);
 
-    void getReadIterator(SampleVector::iterator& readUntil); //!< get iterator past the last sample that was read by a read with signal (i.e. current read iterator)
+    void getReadIterator(SampleVector::iterator& readUntil); //!< get iterator past the last sample of a read advance operation (i.e. current read iterator)
     void getWriteIterator(SampleVector::iterator& writeAt);  //!< get iterator to current item for update - write phase 1
     void bumpIndex(SampleVector::iterator& writeAt);         //!< copy current item to second buffer and bump write index - write phase 2
 

sdrbase/readme.md

@@ -4,7 +4,7 @@
 
 Starting with version 2 SDRangel supports several sampling devices simultaneously. Each concurrent device is associated to a slot with a set of tabbed windows in the UI. These tabs are marked R0, R1, R2... 
 
-The slots are arranged in a stacked fashion so that when a new device is added with the Acquisition -> Add device menu a new slot is allocated in the last position and when a devcie is removed with the Acquisition -> Remove device menu the slot in the last position is deleted. Slot 0 (R0) is created at initialization and cannot be deleted with the menu.
+The slots are arranged in a stacked fashion so that when a new device is added with the Acquisition -> Add device menu a new slot is allocated in the last position and when a devcie is removed with the Acquisition -> Remove device menu the slot in the last position is deleted. Slot 0 (R0) receiver slot is created at initialization and cannot be deleted with the menu. The letter "R" in the tab names indicates that the slot is for a receiver (source) device while "T" designates a tramsmitter (sink) device.
 
 The tabbed windows are:
 
@@ -32,9 +32,10 @@ The following items are presented hierarchically from left to right:
    - Exit (shortcut Ctl-Q): Exit the program
   - View:
    - Fullscreen (Shortcut F11): Toggle full screen mode
-  - Acquisition:
-   - Add device: adds a new sampling device slot to the device stack (last position)
-   - Remove device: removes the last sampling device slot from thte device stack
+  - Devices:
+   - Add source device: adds a new source (receiver) device slot to the device stack (last position)
+   - Add sink device: adds a new sink (transmitter) device slot to the device stack (last position)
+   - Remove device: removes the last device slot from thte device stack
   - Window: presents the list of dockable windows. Check to make it visible. Uncheck to hide. These windows are:
    - Sampling devices control: control of which sampling devices is used and add channels
    - Sampling devices: the sampling devices UIs