P25 - adds direct frequency control for the C4FM symbol filter to adjust the tuner channel for frequency correction.

src/controller/channel/Channel.java

@@ -141,24 +141,21 @@ public class Channel extends Configuration
 	}
 
 	/**
-	 * Indicates if the channel is using Automatic Frequency Control
-	 * @return
+	 * Indicates if the channel has Automatic or Direct Frequency Control
 	 */
-	public boolean hasAFC()
+	public boolean hasFrequencyControl()
 	{
-		return getAFC() != null;
+		return mProcessingChain != null && mProcessingChain.hasFrequencyControl();
 	}
 	
-	public AutomaticFrequencyControl getAFC()
+	public long getFrequencyCorrection()
 	{
-		if( isProcessing() )
+		if( mProcessingChain != null )
 		{
-			return getProcessingChain().getAFC();
-		}
-		else
-		{
-			return null;
+			return mProcessingChain.getFrequencyCorrection();
 		}
+		
+		return 0;
 	}
 
 	/**

src/controller/channel/ProcessingChain.java

@@ -46,6 +46,8 @@ import source.RealSource;
 import source.Source;
 import source.SourceException;
 import source.config.SourceConfigMixer;
+import source.tuner.DirectFrequencyController;
+import source.tuner.FrequencyChangeListener;
 import source.tuner.Tuner;
 import source.tuner.TunerChannelSource;
 import alias.AliasList;
@@ -109,11 +111,28 @@ public class ProcessingChain implements Listener<Message>
 	}
 
 	/**
-	 * Automatic Frequency Control, or null if disabled
+	 * Current frequency correction setting
 	 */
-	public AutomaticFrequencyControl getAFC()
+	public long getFrequencyCorrection()
 	{
-		return mAFC;
+		if( mAFC != null )
+		{
+			return mAFC.getErrorCorrection();
+		}
+		else if( mDecoder != null && 
+				  mDecoder instanceof DirectFrequencyController )
+		{
+			return ( (DirectFrequencyController)mDecoder).getFrequencyCorrection();
+		}
+		
+		return 0;
+	}
+	
+	public boolean hasFrequencyControl()
+	{
+		return mAFC != null || 
+				( mDecoder != null && 
+				  mDecoder instanceof DirectFrequencyController );
 	}
 	
 	public Listener<List<ComplexSample>> getComplexReceiver()
@@ -370,23 +389,31 @@ public class ProcessingChain implements Listener<Message>
 						mAFC = null;
 					}
 					
-					if( mSource instanceof TunerChannelSource &&
-					    mChannel.getDecodeConfiguration().supportsAFC() &&
-						mChannel.getDecodeConfiguration().isAFCEnabled() )
+					if( mSource instanceof TunerChannelSource )
 					{
 						TunerChannelSource tcs = (TunerChannelSource)mSource;
 						
-						int maximumCorrection = mChannel
-							.getDecodeConfiguration().getAFCMaximumCorrection();
-						
-						mAFC = new AutomaticFrequencyControl( tcs, 
-											maximumCorrection );
+						if( mChannel.getDecodeConfiguration().supportsAFC() &&
+							mChannel.getDecodeConfiguration().isAFCEnabled() )
+						{
+							
+							int maximumCorrection = mChannel
+								.getDecodeConfiguration().getAFCMaximumCorrection();
+							
+							mAFC = new AutomaticFrequencyControl( tcs, 
+												maximumCorrection );
 
-						/* Register AFC to receive frequency change events */
-						tcs.addListener( mAFC );
+							/* Register AFC to receive frequency change events */
+							tcs.addListener( mAFC );
 
-						/* Add AFC as listener to the decoder */
-						mDecoder.addUnfilteredRealSampleListener( mAFC );
+							/* Add AFC as listener to the decoder */
+							mDecoder.addUnfilteredRealSampleListener( mAFC );
+						}
+						else if( mDecoder instanceof DirectFrequencyController )
+						{
+							((DirectFrequencyController)mDecoder)
+								.setListener( (FrequencyChangeListener)tcs );
+						}
 					}
 				}
 			}

src/decode/p25/P25Decoder.java

@@ -30,6 +30,8 @@ import org.slf4j.LoggerFactory;
 
 import sample.real.RealSampleListener;
 import source.Source.SampleType;
+import source.tuner.DirectFrequencyController;
+import source.tuner.FrequencyChangeListener;
 import alias.AliasList;
 import decode.Decoder;
 import decode.DecoderType;
@@ -42,7 +44,8 @@ import dsp.fsk.C4FMSymbolFilter;
 import dsp.fsk.P25MessageFramer;
 import dsp.nbfm.FMDiscriminator;
 
-public class P25Decoder extends Decoder implements Instrumentable
+public class P25Decoder extends Decoder 
+			implements DirectFrequencyController, Instrumentable
 {
 	private final static Logger mLog = LoggerFactory.getLogger( P25Decoder.class );
 
@@ -196,4 +199,20 @@ public class P25Decoder extends Decoder implements Instrumentable
 	    throw new IllegalArgumentException( "unfiltered real sample provider "
 	    		+ "not implemented in P25 Decoder" );
     }
+
+	/**
+	 * Registers a frequency change listener to receive frequency correction
+	 * events from the symbol filter
+	 */
+	@Override
+	public void setListener( FrequencyChangeListener listener )
+	{
+		mSymbolFilter.addListener( listener );
+	}
+
+	@Override
+	public long getFrequencyCorrection()
+	{
+		return mSymbolFilter.getFrequencyCorrection();
+	}
 }

src/decode/p25/message/pdu/PDUConfirmedMessage.java

@@ -117,8 +117,24 @@ public class PDUConfirmedMessage extends PDUMessage
 	{
 		/* 16 octets per block, and 12 octets in final block */
 		int count = getBlocksToFollowCount() * 16 - 4;
+
+		int padding = getPadOctetCount();
+		
+		/* Hack: motorola sndcp packet data control - when it says there are 15
+		 * pad octets and only 1 data block of 12 data octets, that means there 
+		 * are more pad octets than available data and they appear to suppress 
+		 * the final padded data block containing the 12 pad octets. The data
+		 * block count should be 2, but it says 1, so they're either not sending
+		 * the final block, or there is an error in the block count */
+		if( padding > count )
+		{
+			count -= ( padding - 12 );
+		}
+		else
+		{
+			count -= padding;
+		}
 		
-		count -= getPadOctetCount();
 		
 		count -= getDataHeaderOffset();
 		

src/dsp/fsk/C4FMSymbolFilter.java

@@ -13,8 +13,13 @@ import org.slf4j.LoggerFactory;
 
 import sample.real.RealSampleListener;
 import sample.real.RealSampleProvider;
+import source.tuner.FrequencyChangeBroadcaster;
+import source.tuner.FrequencyChangeEvent;
+import source.tuner.FrequencyChangeEvent.Attribute;
+import source.tuner.FrequencyChangeListener;
 
-public class C4FMSymbolFilter implements RealSampleListener, 
+public class C4FMSymbolFilter implements FrequencyChangeBroadcaster,
+										 RealSampleListener, 
 										 RealSampleProvider,
 										 Instrumentable
 {
@@ -180,7 +185,8 @@ public class C4FMSymbolFilter implements RealSampleListener,
 	private static final double K_FINE_FREQUENCY = 0.125;
 	
 	/* Frequency correction broadcast threshold */
-	private static final double COARSE_FREQUENCY_DEADBAND = 1.66;
+//	private static final double COARSE_FREQUENCY_DEADBAND = 1.66;
+	private static final double COARSE_FREQUENCY_DEADBAND = 1.20;
 	
 	/* 2.0 symbol spread gives -3, -1, 1, 3 */
 	private float mSymbolSpread = 2.0f;
@@ -194,6 +200,9 @@ public class C4FMSymbolFilter implements RealSampleListener,
 	private int mHistoryLast = 0;
 	
 	private RealSampleListener mListener;
+	
+	private FrequencyChangeListener mFrequencyChangeListener;
+	private long mFrequencyCorrection;
 
 	private float mGain = 15.4f;
 	
@@ -219,6 +228,11 @@ public class C4FMSymbolFilter implements RealSampleListener,
 	{
 	}
 	
+	public long getFrequencyCorrection()
+	{
+		return mFrequencyCorrection;
+	}
+	
 	@Override
     public void receive( float sample )
     {
@@ -311,13 +325,24 @@ public class C4FMSymbolFilter implements RealSampleListener,
 			
 			mFineFrequencyCorrection += ( symbolError * K_FINE_FREQUENCY );
 			
-//			/* send frequency correction */
-//			if( Math.abs( mCoarseFrequencyCorrection ) > COARSE_FREQUENCY_DEADBAND )
-//			{
-//				mLog.debug( "Frequency Correction [" + 
-//						( mCoarseFrequencyCorrection > 0 ? "-" : "+" ) + 
-//						mCoarseFrequencyCorrection + "]" );
-//			}
+			/* send frequency correction */
+			if( Math.abs( mCoarseFrequencyCorrection ) > COARSE_FREQUENCY_DEADBAND )
+			{
+				if( mFrequencyChangeListener != null )
+				{
+					mFrequencyCorrection += ( 
+						500 * ( mCoarseFrequencyCorrection > 0 ? 1 : -1 ) );
+					
+					mFrequencyChangeListener.frequencyChanged( 
+						new FrequencyChangeEvent( Attribute.FREQUENCY_ERROR, 
+								mFrequencyCorrection ) );
+
+					/* reset internal frequency error tracker */
+					mCoarseFrequencyCorrection = 0;
+
+					mLog.debug( "Frequency Corrected: " + mFrequencyCorrection );
+				}
+			}
 			
 			if( mSymbolSpreadTap != null )
 			{
@@ -343,7 +368,7 @@ public class C4FMSymbolFilter implements RealSampleListener,
     {
 		mListener = null;
     }
-
+	
 	@Override
     public List<Tap> getTaps()
     {
@@ -379,4 +404,16 @@ public class C4FMSymbolFilter implements RealSampleListener,
 			mSymbolSpreadTap = null;
 		}
     }
+
+	@Override
+	public void addListener( FrequencyChangeListener listener )
+	{
+		mFrequencyChangeListener = listener;
+	}
+
+	@Override
+	public void removeListener( FrequencyChangeListener listener )
+	{
+		mFrequencyChangeListener = null;
+	}
 }

src/source/tuner/DirectFrequencyController.java

@@ -0,0 +1,9 @@
+package source.tuner;
+
+
+public interface DirectFrequencyController
+{
+	public void setListener( FrequencyChangeListener listener );
+	
+	public long getFrequencyCorrection();
+}

src/spectrum/OverlayPanel.java

@@ -500,11 +500,11 @@ public class OverlayPanel extends JPanel
                 }
                 
                 /* Draw Automatic Frequency Control line */
-                if( channel.hasAFC() )
+                if( channel.hasFrequencyControl() )
                 {
-                	int frequency = (int)tunerChannel.getFrequency();
+                	long frequency = tunerChannel.getFrequency();
                 	
-                	int error = frequency + channel.getAFC().getErrorCorrection();
+                	long error = frequency + channel.getFrequencyCorrection();
                 	
                     drawAFC( graphics, getAxisFromFrequency( frequency ), false );