diff --git a/MMDVMHost.vcxproj b/MMDVMHost.vcxproj
index 83cba81..0491601 100644
--- a/MMDVMHost.vcxproj
+++ b/MMDVMHost.vcxproj
@@ -194,6 +194,7 @@
     <ClInclude Include="NetworkInfo.h" />
     <ClInclude Include="Nextion.h" />
     <ClInclude Include="NullDisplay.h" />
+    <ClInclude Include="NullModem.h" />
     <ClInclude Include="NXDNAudio.h" />
     <ClInclude Include="NXDNControl.h" />
     <ClInclude Include="NXDNConvolution.h" />
@@ -282,6 +283,7 @@
     <ClCompile Include="NetworkInfo.cpp" />
     <ClCompile Include="Nextion.cpp" />
     <ClCompile Include="NullDisplay.cpp" />
+    <ClCompile Include="NullModem.cpp" />
     <ClCompile Include="NXDNAudio.cpp" />
     <ClCompile Include="NXDNControl.cpp" />
     <ClCompile Include="NXDNConvolution.cpp" />
@@ -327,4 +329,4 @@
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
   </ImportGroup>
-</Project>
+</Project>
\ No newline at end of file
diff --git a/MMDVMHost.vcxproj.filters b/MMDVMHost.vcxproj.filters
index 200ee23..a91deba 100644
--- a/MMDVMHost.vcxproj.filters
+++ b/MMDVMHost.vcxproj.filters
@@ -278,6 +278,9 @@
     <ClInclude Include="MobileGPS.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="NullModem.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="BPTC19696.cpp">
@@ -520,5 +523,8 @@
     <ClCompile Include="MobileGPS.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="NullModem.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
-</Project>
+</Project>
\ No newline at end of file
diff --git a/Makefile b/Makefile
index ea2597d..44502b2 100644
--- a/Makefile
+++ b/Makefile
@@ -9,11 +9,11 @@ LDFLAGS = -g
 OBJECTS = \
 		AMBEFEC.o BCH.o BPTC19696.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o DMREMB.o DMREmbeddedData.o DMRFullLC.o \
 		DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o DMRAccessControl.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o \
-		DStarSlowData.o Golay2087.o Golay24128.o Hamming.o I2CController.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o ModemSerialPort.o Mutex.o NetworkInfo.o \
-		Nextion.o NullDisplay.o NullModem.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNLayer3.o NXDNLICH.o NXDNLookup.o NXDNNetwork.o \
-		NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o P25Trellis.o P25Utils.o POCSAGControl.o \
-		POCSAGNetwork.o QR1676.o RS129.o RS241213.o RSSIInterpolator.o SerialController.o SerialPort.o SHA256.o StopWatch.o Sync.o TFTSerial.o Thread.o \
-		Timer.o UDPSocket.o UMP.o Utils.o YSFControl.o YSFConvolution.o YSFFICH.o YSFNetwork.o YSFPayload.o
+		DStarSlowData.o Golay2087.o Golay24128.o Hamming.o I2CController.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o ModemSerialPort.o Mutex.o
+		NetworkInfo.o Nextion.o NullDisplay.o NullModem.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNLayer3.o NXDNLICH.o \
+		NXDNLookup.o NXDNNetwork.o NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o P25Trellis.o P25Utils.o \
+		POCSAGControl.o POCSAGNetwork.o QR1676.o RS129.o RS241213.o RSSIInterpolator.o SerialController.o SerialPort.o SHA256.o StopWatch.o Sync.o TFTSerial.o \
+		Thread.o Timer.o UDPSocket.o UMP.o Utils.o YSFControl.o YSFConvolution.o YSFFICH.o YSFNetwork.o YSFPayload.o
 
 all:		MMDVMHost
 
diff --git a/Makefile.Pi b/Makefile.Pi
index dc8e1aa..3a19521 100644
--- a/Makefile.Pi
+++ b/Makefile.Pi
@@ -9,11 +9,11 @@ LDFLAGS = -g -L/usr/local/lib
 OBJECTS = \
 		AMBEFEC.o BCH.o BPTC19696.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o DMREMB.o DMREmbeddedData.o DMRFullLC.o \
 		DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o DMRAccessControl.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o \
-		DStarSlowData.o Golay2087.o Golay24128.o Hamming.o I2CController.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o ModemSerialPort.o Mutex.o NetworkInfo.o Nextion.o \
-		NullDisplay.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNLayer3.o NXDNLICH.o NXDNLookup.o NXDNNetwork.o NXDNSACCH.o \
-		NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o P25Trellis.o P25Utils.o POCSAGControl.o POCSAGNetwork.o \
-		QR1676.o RS129.o RS241213.o RSSIInterpolator.o SerialController.o SerialPort.o SHA256.o StopWatch.o Sync.o TFTSerial.o Thread.o Timer.o UDPSocket.o \
-		UMP.o Utils.o YSFControl.o YSFConvolution.o YSFFICH.o YSFNetwork.o YSFPayload.o
+		DStarSlowData.o Golay2087.o Golay24128.o Hamming.o I2CController.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o ModemSerialPort.o Mutex.o \
+		NetworkInfo.o Nextion.o NullDisplay.o NullModem.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNLayer3.o NXDNLICH.o NXDNLookup.o \
+		NXDNNetwork.o NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o P25Trellis.o P25Utils.o POCSAGControl.o \
+		POCSAGNetwork.o QR1676.o RS129.o RS241213.o RSSIInterpolator.o SerialController.o SerialPort.o SHA256.o StopWatch.o Sync.o TFTSerial.o Thread.o Timer.o \
+		UDPSocket.o UMP.o Utils.o YSFControl.o YSFConvolution.o YSFFICH.o YSFNetwork.o YSFPayload.o
 
 all:		MMDVMHost
 
diff --git a/Makefile.Pi.Adafruit b/Makefile.Pi.Adafruit
index 1065ed3..2ffa9fb 100644
--- a/Makefile.Pi.Adafruit
+++ b/Makefile.Pi.Adafruit
@@ -9,9 +9,9 @@ LDFLAGS = -g -L/usr/local/lib
 OBJECTS = \
 		AMBEFEC.o BCH.o BPTC19696.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o DMREMB.o DMREmbeddedData.o DMRFullLC.o \
 		DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o DMRAccessControl.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o \
-		DStarSlowData.o Golay2087.o Golay24128.o Hamming.o HD44780.o I2CController.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o ModemSerialPort.o Mutex.o NetworkInfo.o \
-		Nextion.o NullDisplay.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNLayer3.o NXDNLICH.o NXDNLookup.o NXDNNetwork.o \
-		NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o P25Trellis.o P25Utils.o POCSAGControl.o \
+		DStarSlowData.o Golay2087.o Golay24128.o Hamming.o HD44780.o I2CController.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o ModemSerialPort.o Mutex.o \
+		NetworkInfo.o Nextion.o NullDisplay.o NullModem.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNLayer3.o NXDNLICH.o NXDNLookup.o \
+		NXDNNetwork.o NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o P25Trellis.o P25Utils.o POCSAGControl.o \
 		POCSAGNetwork.o QR1676.o RS129.o RS241213.o RSSIInterpolator.o SerialController.o SerialPort.o SHA256.o StopWatch.o Sync.o TFTSerial.o Thread.o \
 		Timer.o UDPSocket.o UMP.o Utils.o YSFControl.o YSFConvolution.o YSFFICH.o YSFNetwork.o YSFPayload.o
 
diff --git a/Makefile.Pi.HD44780 b/Makefile.Pi.HD44780
index fd3c32f..c70c081 100644
--- a/Makefile.Pi.HD44780
+++ b/Makefile.Pi.HD44780
@@ -9,9 +9,9 @@ LDFLAGS = -g -L/usr/local/lib
 OBJECTS = \
 		AMBEFEC.o BCH.o BPTC19696.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o DMREMB.o DMREmbeddedData.o DMRFullLC.o \
 		DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o DMRAccessControl.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o \
-		DStarSlowData.o Golay2087.o Golay24128.o Hamming.o HD44780.o I2CController.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o ModemSerialPort.o Mutex.o NetworkInfo.o \
-		Nextion.o NullDisplay.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNLayer3.o NXDNLICH.o NXDNLookup.o NXDNNetwork.o \
-		NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o P25Trellis.o P25Utils.o POCSAGControl.o \
+		DStarSlowData.o Golay2087.o Golay24128.o Hamming.o HD44780.o I2CController.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o ModemSerialPort.o Mutex.o \
+		NetworkInfo.o Nextion.o NullDisplay.o NullModem.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNLayer3.o NXDNLICH.o NXDNLookup.o \
+		NXDNNetwork.o NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o P25Trellis.o P25Utils.o POCSAGControl.o \
 		POCSAGNetwork.o QR1676.o RS129.o RS241213.o RSSIInterpolator.o SerialController.o SerialPort.o SHA256.o StopWatch.o Sync.o TFTSerial.o Thread.o \
 		Timer.o UDPSocket.o UMP.o Utils.o YSFControl.o YSFConvolution.o YSFFICH.o YSFNetwork.o YSFPayload.o
 
diff --git a/Makefile.Pi.OLED b/Makefile.Pi.OLED
index 9c17f06..542b804 100644
--- a/Makefile.Pi.OLED
+++ b/Makefile.Pi.OLED
@@ -9,9 +9,9 @@ LDFLAGS = -g -L/usr/local/lib
 OBJECTS = \
 		AMBEFEC.o BCH.o BPTC19696.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o DMREMB.o DMREmbeddedData.o DMRFullLC.o \
 		DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o DMRAccessControl.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o \
-		DStarSlowData.o Golay2087.o Golay24128.o Hamming.o I2CController.o OLED.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o ModemSerialPort.o Mutex.o NetworkInfo.o \
-		Nextion.o NullDisplay.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNLayer3.o NXDNLICH.o NXDNLookup.o NXDNNetwork.o \
-		NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o P25Trellis.o P25Utils.o POCSAGControl.o \
+		DStarSlowData.o Golay2087.o Golay24128.o Hamming.o I2CController.o OLED.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o ModemSerialPort.o Mutex.o \
+		NetworkInfo.o Nextion.o NullDisplay.o NullModem.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNLayer3.o NXDNLICH.o NXDNLookup.o \
+		NXDNNetwork.o NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o P25Trellis.o P25Utils.o POCSAGControl.o \
 		POCSAGNetwork.o QR1676.o RS129.o RS241213.o RSSIInterpolator.o SerialController.o SerialPort.o SHA256.o StopWatch.o Sync.o TFTSerial.o Thread.o \
 		Timer.o UDPSocket.o UMP.o Utils.o YSFControl.o YSFConvolution.o YSFFICH.o YSFNetwork.o YSFPayload.o
 
diff --git a/Makefile.Pi.PCF8574 b/Makefile.Pi.PCF8574
index 29dba7c..fc4a73e 100644
--- a/Makefile.Pi.PCF8574
+++ b/Makefile.Pi.PCF8574
@@ -9,9 +9,9 @@ LDFLAGS = -g -L/usr/local/lib
 OBJECTS = \
 		AMBEFEC.o BCH.o BPTC19696.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o DMREMB.o DMREmbeddedData.o DMRFullLC.o \
 		DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o DMRAccessControl.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o \
-		DStarSlowData.o Golay2087.o Golay24128.o Hamming.o HD44780.o I2CController.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o ModemSerialPort.o Mutex.o NetworkInfo.o \
-		Nextion.o NullDisplay.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNLayer3.o NXDNLICH.o NXDNLookup.o NXDNNetwork.o \
-		NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o P25Trellis.o P25Utils.o POCSAGControl.o \
+		DStarSlowData.o Golay2087.o Golay24128.o Hamming.o HD44780.o I2CController.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o ModemSerialPort.o Mutex.o \
+		NetworkInfo.o Nextion.o NullDisplay.o NullModem.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNLayer3.o NXDNLICH.o NXDNLookup.o \
+		NXDNNetwork.o NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o P25Trellis.o P25Utils.o POCSAGControl.o \
 		POCSAGNetwork.o QR1676.o RS129.o RS241213.o RSSIInterpolator.o SerialController.o SerialPort.o SHA256.o StopWatch.o Sync.o TFTSerial.o Thread.o \
 		Timer.o UDPSocket.o UMP.o Utils.o YSFControl.o YSFConvolution.o YSFFICH.o YSFNetwork.o YSFPayload.o
 
diff --git a/Makefile.Solaris b/Makefile.Solaris
index b82ee32..6691d3e 100644
--- a/Makefile.Solaris
+++ b/Makefile.Solaris
@@ -10,8 +10,8 @@ OBJECTS = \
 		AMBEFEC.o BCH.o BPTC19696.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o DMREMB.o DMREmbeddedData.o DMRFullLC.o \
 		DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o DMRAccessControl.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o \
 		DStarSlowData.o Golay2087.o Golay24128.o Hamming.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o ModemSerialPort.o Mutex.o NetworkInfo.o Nextion.o \
-		NullDisplay.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNLayer3.o NXDNLICH.o NXDNLookup.o NXDNNetwork.o NXDNSACCH.o \
-		NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o P25Trellis.o P25Utils.o POCSAGControl.o POCSAGNetwork.o \
+		NullDisplay.o NullModem.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNLayer3.o NXDNLICH.o NXDNLookup.o NXDNNetwork.o \
+		NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o P25Trellis.o P25Utils.o POCSAGControl.o POCSAGNetwork.o \
 		QR1676.o RS129.o RS241213.o RSSIInterpolator.o SerialController.o SerialPort.o SHA256.o StopWatch.o Sync.o TFTSerial.o Thread.o Timer.o UDPSocket.o \
 		UMP.o Utils.o YSFControl.o YSFConvolution.o YSFFICH.o YSFNetwork.o YSFPayload.o