From 51e74c6182b75aa00d47f90f677b351ae3dd01c6 Mon Sep 17 00:00:00 2001
From: SASANO Takayoshi <uaa@uaa.org.uk>
Date: Wed, 10 Mar 2021 21:09:58 +0900
Subject: [PATCH 01/23] revise UserDB display setting on OLED

To display UserDB on OLED, either Slot1=0/Slot2=1 or Slot1=1/Slot2=0
of [DMR Network] in MMDVM.ini was required.

Other displays such as LCDproc, HD44180 and TFTSurenoo uses duplex value of
[General], OLED also uses same entry from now.
---
 Display.cpp |  2 +-
 OLED.cpp    | 10 +++++-----
 OLED.h      |  4 ++--
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/Display.cpp b/Display.cpp
index 39b0a09..516d76d 100644
--- a/Display.cpp
+++ b/Display.cpp
@@ -642,7 +642,7 @@ CDisplay* CDisplay::createDisplay(const CConf& conf, CUMP* ump, CModem* modem)
 		bool          rotate     = conf.getOLEDRotate();
 		bool          logosaver  = conf.getOLEDLogoScreensaver();
 
-		display = new COLED(type, brightness, invert, scroll, rotate, logosaver, conf.getDMRNetworkSlot1(), conf.getDMRNetworkSlot2());
+		display = new COLED(type, brightness, invert, scroll, rotate, logosaver, conf.getDuplex());
 #endif
 	} else if (type == "CAST") {
 		display = new CCASTInfo(modem);
diff --git a/OLED.cpp b/OLED.cpp
index 34365aa..fddbe4d 100644
--- a/OLED.cpp
+++ b/OLED.cpp
@@ -169,15 +169,15 @@ const unsigned char logo_POCSAG_bmp [] =
 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
 };
 
-COLED::COLED(unsigned char displayType, unsigned char displayBrightness, bool displayInvert, bool displayScroll, bool displayRotate, bool displayLogoScreensaver, bool slot1Enabled, bool slot2Enabled) :
+COLED::COLED(unsigned char displayType, unsigned char displayBrightness, bool displayInvert, bool displayScroll, bool displayRotate, bool displayLogoScreensaver, bool duplex) :
 m_displayType(displayType),
 m_displayBrightness(displayBrightness),
 m_displayInvert(displayInvert),
 m_displayScroll(displayScroll),
 m_displayRotate(displayRotate),
 m_displayLogoScreensaver(displayLogoScreensaver),
-m_slot1Enabled(slot1Enabled),
-m_slot2Enabled(slot2Enabled),
+m_duplex(duplex),
+//m_duplex(true),         // uncomment to force duplex display for testing!
 m_ipaddress(),
 m_display()
 {
@@ -382,7 +382,7 @@ int COLED::writeDMRIntEx(unsigned int slotNo, const class CUserDBentry& src, boo
     }
     // if both slots, use lines 2-3 for slot 1, lines 4-5 for slot 2
     // if single slot, use lines 2-3
-    if ( m_slot1Enabled && m_slot2Enabled ) {
+    if ( m_duplex ) {
 
         if (slotNo == 1U) {
             m_display.fillRect(0,OLED_LINE2,m_display.width(),40,BLACK);
@@ -430,7 +430,7 @@ void COLED::clearDMRInt(unsigned int slotNo)
 {
     // if both slots, use lines 2-3 for slot 1, lines 4-5 for slot 2
     // if single slot, use lines 2-3
-    if ( m_slot1Enabled && m_slot2Enabled ){
+    if ( m_duplex ){
         if (slotNo == 1U) {
             m_display.fillRect(0, OLED_LINE3, m_display.width(), 40, BLACK);
             m_display.setCursor(0,OLED_LINE3);
diff --git a/OLED.h b/OLED.h
index 5f3ead0..a703ba5 100644
--- a/OLED.h
+++ b/OLED.h
@@ -41,7 +41,7 @@
 class COLED : public CDisplay 
 {
 public:
-  COLED(unsigned char displayType, unsigned char displayBrighness, bool displayInvert, bool displayScroll, bool displayRotate, bool displayLogoScreensaver, bool slot1Enabled, bool slot2Enabled);
+  COLED(unsigned char displayType, unsigned char displayBrighness, bool displayInvert, bool displayScroll, bool displayRotate, bool displayLogoScreensaver, bool duplex);
   virtual ~COLED();
 
   virtual bool open();
@@ -88,7 +88,7 @@ private:
   bool          m_displayScroll;
   bool          m_displayRotate;
   bool          m_displayLogoScreensaver;
-  bool          m_slot1Enabled;
+  bool          m_duplex;
   bool          m_slot2Enabled;
   std::string   m_ipaddress;
   ArduiPi_OLED  m_display;

From 125f21735bedb1c56ee7fc732847f74884067737 Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Fri, 12 Mar 2021 19:56:05 +0000
Subject: [PATCH 02/23] Move the host lookup for the DMR Direct Network.

---
 DMRDirectNetwork.cpp | 7 +++----
 DMRDirectNetwork.h   | 4 +++-
 Version.h            | 2 +-
 3 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/DMRDirectNetwork.cpp b/DMRDirectNetwork.cpp
index 8bb397f..4ed871c 100644
--- a/DMRDirectNetwork.cpp
+++ b/DMRDirectNetwork.cpp
@@ -31,6 +31,8 @@ const unsigned int HOMEBREW_DATA_PACKET_LENGTH = 55U;
 
 
 CDMRDirectNetwork::CDMRDirectNetwork(const std::string& address, unsigned int port, unsigned int local, unsigned int id, const std::string& password, bool duplex, const char* version, bool slot1, bool slot2, HW_TYPE hwType, bool debug) :
+m_address(address),
+m_port(port),
 m_addr(),
 m_addrLen(0U),
 m_id(NULL),
@@ -70,9 +72,6 @@ m_beacon(false)
 	assert(id > 1000U);
 	assert(!password.empty());
 
-	if (CUDPSocket::lookup(address, port, m_addr, m_addrLen) != 0)
-		m_addrLen = 0U;
-
 	m_buffer   = new unsigned char[BUFFER_LENGTH];
 	m_salt     = new unsigned char[sizeof(uint32_t)];
 	m_id       = new uint8_t[4U];
@@ -122,7 +121,7 @@ void CDMRDirectNetwork::setConfig(const std::string& callsign, unsigned int rxFr
 
 bool CDMRDirectNetwork::open()
 {
-	if (m_addrLen == 0U) {
+	if (CUDPSocket::lookup(m_address, m_port, m_addr, m_addrLen) != 0) {
 		LogError("DMR, Could not lookup the address of the DMR Network");
 		return false;
 	}
diff --git a/DMRDirectNetwork.h b/DMRDirectNetwork.h
index 896d5e4..30ba951 100644
--- a/DMRDirectNetwork.h
+++ b/DMRDirectNetwork.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2017,2018,2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2017,2018,2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -58,6 +58,8 @@ public:
 	virtual void close();
 
 private:
+	std::string      m_address;
+	unsigned int     m_port;
 	sockaddr_storage m_addr;
 	unsigned int     m_addrLen;
 	uint8_t*         m_id;
diff --git a/Version.h b/Version.h
index 8a94573..6e4502f 100644
--- a/Version.h
+++ b/Version.h
@@ -19,6 +19,6 @@
 #if !defined(VERSION_H)
 #define	VERSION_H
 
-const char* VERSION = "20210309";
+const char* VERSION = "20210312";
 
 #endif

From c2be5ab2f782b83f132019030eadc94d3f436689 Mon Sep 17 00:00:00 2001
From: SASANO Takayoshi <uaa@uaa.org.uk>
Date: Sat, 13 Mar 2021 12:27:23 +0900
Subject: [PATCH 03/23] delete unused variable

---
 OLED.h | 1 -
 1 file changed, 1 deletion(-)

diff --git a/OLED.h b/OLED.h
index a703ba5..3f63226 100644
--- a/OLED.h
+++ b/OLED.h
@@ -89,7 +89,6 @@ private:
   bool          m_displayRotate;
   bool          m_displayLogoScreensaver;
   bool          m_duplex;
-  bool          m_slot2Enabled;
   std::string   m_ipaddress;
   ArduiPi_OLED  m_display;
 

From fb0d1ef5e21f110c735630bf3ec8972ba42e6180 Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Sun, 14 Mar 2021 12:16:39 +0000
Subject: [PATCH 04/23] Allow the USRP audio format to be used natively by the
 FM networking.

---
 Conf.cpp      |  10 +++-
 Conf.h        |   2 +
 FMNetwork.cpp | 151 +++++++++++++++++++++++++++++++++++++-------------
 FMNetwork.h   |  13 ++++-
 MMDVM.ini     |   2 +
 MMDVMHost.cpp |   4 +-
 Version.h     |   2 +-
 7 files changed, 139 insertions(+), 45 deletions(-)

diff --git a/Conf.cpp b/Conf.cpp
index 7c9f478..d69d297 100644
--- a/Conf.cpp
+++ b/Conf.cpp
@@ -283,6 +283,7 @@ m_pocsagLocalPort(0U),
 m_pocsagNetworkModeHang(3U),
 m_pocsagNetworkDebug(false),
 m_fmNetworkEnabled(false),
+m_fmNetworkFormat("MMDVM"),
 m_fmGatewayAddress(),
 m_fmGatewayPort(0U),
 m_fmLocalAddress(),
@@ -440,7 +441,7 @@ bool CConf::read()
 			value++;
 		} else {
 			// if value is not quoted, remove after # (to make comment)
-			::strtok(value, "#");
+			(void)::strtok(value, "#");
 		}
 
 		if (section == SECTION_GENERAL) {
@@ -998,6 +999,8 @@ bool CConf::read()
 		} else if (section == SECTION_FM_NETWORK) {
 			if (::strcmp(key, "Enable") == 0)
 				m_fmNetworkEnabled = ::atoi(value) == 1;
+			else if (::strcmp(key, "Format") == 0)
+				m_fmNetworkFormat = value;
 			else if (::strcmp(key, "LocalAddress") == 0)
 				m_fmLocalAddress = value;
 			else if (::strcmp(key, "LocalPort") == 0)
@@ -2197,6 +2200,11 @@ bool CConf::getFMNetworkEnabled() const
 	return m_fmNetworkEnabled;
 }
 
+std::string CConf::getFMNetworkFormat() const
+{
+	return m_fmNetworkFormat;
+}
+
 std::string CConf::getFMGatewayAddress() const
 {
 	return m_fmGatewayAddress;
diff --git a/Conf.h b/Conf.h
index 430bbeb..7a5c56a 100644
--- a/Conf.h
+++ b/Conf.h
@@ -296,6 +296,7 @@ public:
 
   // The FM Network section
   bool         getFMNetworkEnabled() const;
+  std::string  getFMNetworkFormat() const;
   std::string  getFMGatewayAddress() const;
   unsigned int getFMGatewayPort() const;
   std::string  getFMLocalAddress() const;
@@ -603,6 +604,7 @@ private:
   bool         m_pocsagNetworkDebug;
 
   bool         m_fmNetworkEnabled;
+  std::string  m_fmNetworkFormat;
   std::string  m_fmGatewayAddress;
   unsigned int m_fmGatewayPort;
   std::string  m_fmLocalAddress;
diff --git a/FMNetwork.cpp b/FMNetwork.cpp
index c10e3d8..d9aa0e5 100644
--- a/FMNetwork.cpp
+++ b/FMNetwork.cpp
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -27,7 +27,8 @@
 
 const unsigned int BUFFER_LENGTH = 500U;
 
-CFMNetwork::CFMNetwork(const std::string& localAddress, unsigned int localPort, const std::string& gatewayAddress, unsigned int gatewayPort, unsigned int sampleRate, bool debug) :
+CFMNetwork::CFMNetwork(const std::string& format, const std::string& localAddress, unsigned int localPort, const std::string& gatewayAddress, unsigned int gatewayPort, unsigned int sampleRate, bool debug) :
+m_format(FMF_MMDVM),
 m_socket(localAddress, localPort),
 m_addr(),
 m_addrLen(0U),
@@ -35,7 +36,8 @@ m_sampleRate(sampleRate),
 m_debug(debug),
 m_enabled(false),
 m_buffer(2000U, "FM Network"),
-m_pollTimer(1000U, 5U)
+m_pollTimer(1000U, 5U),
+m_seqNo(0U)
 {
 	assert(gatewayPort > 0U);
 	assert(!gatewayAddress.empty());
@@ -44,6 +46,9 @@ m_pollTimer(1000U, 5U)
 	if (CUDPSocket::lookup(gatewayAddress, gatewayPort, m_addr, m_addrLen) != 0)
 		m_addrLen = 0U;
 
+	if (format == "USRP")
+		m_format = FMF_USRP;
+
 #if !defined(_WIN32) && !defined(_WIN64)
 	int error;
 	m_incoming = ::src_new(SRC_SINC_FASTEST, 1, &error);
@@ -106,46 +111,97 @@ bool CFMNetwork::writeData(float* data, unsigned int nSamples)
 	}
 #endif
 
-	unsigned int length = 3U;
+	unsigned char buffer[2000U];
+	::memset(buffer, 0x00U, 2000U);
 
-	unsigned char buffer[1500U];
-	::memset(buffer, 0x00U, 1500U);
+	unsigned int length = 0U;
 
-	buffer[0U] = 'F';
-	buffer[1U] = 'M';
-	buffer[2U] = 'D';
+	if (m_format == FMF_USRP) {
+		buffer[length++] = 'U';
+		buffer[length++] = 'S';
+		buffer[length++] = 'R';
+		buffer[length++] = 'P';
+
+		// Sequence number
+		buffer[length++] = (m_seqNo >> 24) & 0xFFU;
+		buffer[length++] = (m_seqNo >> 16) & 0xFFU;
+		buffer[length++] = (m_seqNo >> 8)  & 0xFFU;
+		buffer[length++] = (m_seqNo >> 0)  & 0xFFU;
+
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+
+		// PTT, this may be wrong
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x01U;
+
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+
+		// Type, 0 for audio
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+		buffer[length++] = 0x00U;
+	} else {
+		buffer[length++] = 'F';
+		buffer[length++] = 'M';
+		buffer[length++] = 'D';
+	}
 
 #if defined(_WIN32) || defined(_WIN64)
-	for (long i = 0L; i < nSamples; i++) {
-		 short val = ( short)((data[i] ) * 32767.0F);	// Changing audio format from  U16BE to S16LE
+	for (unsigned int i = 0U; i < nSamples; i++) {
+		 short val = short(data[i] * 32767.0F + 0.5F);			// Changing audio format from float to S16LE
 #else
 	for (long i = 0L; i < src.output_frames_gen; i++) {
-		 short val = ( short)((src.data_out[i] ) * 32767.0F );	// Changing audio format from  U16BE to S16LE
+		 short val = short(src.data_out[i] * 32767.0F + 0.5F);	// Changing audio format from float to S16LE
 #endif
 
-		buffer[length++] = (val >> 0) & 0xFFU;	// changing from  BE to LE
-		buffer[length++] = (val >> 8) & 0xFFU;	// changing from  BE to LE
+		buffer[length++] = (val >> 0) & 0xFFU;
+		buffer[length++] = (val >> 8) & 0xFFU;
 	}
 
 	if (m_debug)
 		CUtils::dump(1U, "FM Network Data Sent", buffer, length);
 
+	m_seqNo++;
+
 	return m_socket.write(buffer, length, m_addr, m_addrLen);
 }
 
 bool CFMNetwork::writeEOT()
 {
-	unsigned char buffer[10U];
-	::memset(buffer, 0x00U, 10U);
+	if (m_format == FMF_MMDVM) {
+		unsigned char buffer[10U];
+		::memset(buffer, 0x00U, 10U);
 
-	buffer[0U] = 'F';
-	buffer[1U] = 'M';
-	buffer[2U] = 'E';
+		buffer[0U] = 'F';
+		buffer[1U] = 'M';
+		buffer[2U] = 'E';
 
-	if (m_debug)
-		CUtils::dump(1U, "FM Network End of Transmission Sent", buffer, 3U);
+		if (m_debug)
+			CUtils::dump(1U, "FM Network End of Transmission Sent", buffer, 3U);
 
-	return m_socket.write(buffer, 3U, m_addr, m_addrLen);
+		return m_socket.write(buffer, 3U, m_addr, m_addrLen);
+	}
+
+	return true;
 }
 
 void CFMNetwork::clock(unsigned int ms)
@@ -170,21 +226,36 @@ void CFMNetwork::clock(unsigned int ms)
 	//	return;
 	//}
 
-	// Ignore incoming polls
-	if (::memcmp(buffer, "FMP", 3U) == 0)
-		return;
-
-	// Invalid packet type?
-	if (::memcmp(buffer, "FMD", 3U) != 0)
-		return;
-
 	if (!m_enabled)
 		return;
 
 	if (m_debug)
 		CUtils::dump(1U, "FM Network Data Received", buffer, length);
 
-	m_buffer.addData(buffer + 3U, length - 3U);
+	if (m_format == FMF_USRP) {
+		// Invalid packet type?
+		if (::memcmp(buffer, "USRP", 4U) != 0)
+			return;
+
+		// The type is a big-endian 4-byte integer
+		unsigned int type = (buffer[20U] << 24) +
+							(buffer[21U] << 16) +
+							(buffer[22U] << 8)  +
+							(buffer[23U] << 0);
+
+		if (type == 0U)
+			m_buffer.addData(buffer + 32U, length - 32U);
+	} else {
+		// Ignore incoming polls
+		if (::memcmp(buffer, "FMP", 3U) == 0)
+			return;
+
+		// Invalid packet type?
+		if (::memcmp(buffer, "FMD", 3U) != 0)
+			return;
+
+		m_buffer.addData(buffer + 3U, length - 3U);
+	}
 }
 
 unsigned int CFMNetwork::read(float* data, unsigned int nSamples)
@@ -274,16 +345,18 @@ void CFMNetwork::enable(bool enabled)
 	m_enabled = enabled;
 }
 
-bool CFMNetwork::writePoll()
+void CFMNetwork::writePoll()
 {
-	unsigned char buffer[3U];
+	if (m_format == FMF_MMDVM) {
+		unsigned char buffer[3U];
 
-	buffer[0U] = 'F';
-	buffer[1U] = 'M';
-	buffer[2U] = 'P';
+		buffer[0U] = 'F';
+		buffer[1U] = 'M';
+		buffer[2U] = 'P';
 
-	if (m_debug)
-		CUtils::dump(1U, "FM Network Poll Sent", buffer, 3U);
+		if (m_debug)
+			CUtils::dump(1U, "FM Network Poll Sent", buffer, 3U);
 
-	return m_socket.write(buffer, 3U, m_addr, m_addrLen);
+		m_socket.write(buffer, 3U, m_addr, m_addrLen);
+	}
 }
diff --git a/FMNetwork.h b/FMNetwork.h
index aa99751..d7b1ff7 100644
--- a/FMNetwork.h
+++ b/FMNetwork.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -30,9 +30,14 @@
 #include <cstdint>
 #include <string>
 
+enum FM_FORMAT {
+	FMF_MMDVM,
+	FMF_USRP
+};
+
 class CFMNetwork {
 public:
-	CFMNetwork(const std::string& myAddress, unsigned int myPort, const std::string& gatewayAddress, unsigned int gatewayPort, unsigned int sampleRate, bool debug);
+	CFMNetwork(const std::string& format, const std::string& myAddress, unsigned int myPort, const std::string& gatewayAddress, unsigned int gatewayPort, unsigned int sampleRate, bool debug);
 	~CFMNetwork();
 
 	bool open();
@@ -52,6 +57,7 @@ public:
 	void clock(unsigned int ms);
 
 private:
+	FM_FORMAT        m_format;
 	CUDPSocket       m_socket;
 	sockaddr_storage m_addr;
 	unsigned int     m_addrLen;
@@ -60,12 +66,13 @@ private:
 	bool             m_enabled;
 	CRingBuffer<unsigned char> m_buffer;
 	CTimer           m_pollTimer;
+	unsigned int     m_seqNo;
 #if !defined(_WIN32) && !defined(_WIN64)
 	SRC_STATE*       m_incoming;
 	SRC_STATE*       m_outgoing;
 #endif
 
-	bool writePoll();
+	void writePoll();
 };
 
 #endif
diff --git a/MMDVM.ini b/MMDVM.ini
index 8c89a56..255c12d 100644
--- a/MMDVM.ini
+++ b/MMDVM.ini
@@ -275,6 +275,8 @@ Debug=0
 
 [FM Network]
 Enable=1
+# Values are MMDVM and USRP
+Format=USRP
 LocalAddress=127.0.0.1
 LocalPort=3810
 GatewayAddress=127.0.0.1
diff --git a/MMDVMHost.cpp b/MMDVMHost.cpp
index 428aa1c..b78d7e9 100644
--- a/MMDVMHost.cpp
+++ b/MMDVMHost.cpp
@@ -1796,6 +1796,7 @@ bool CMMDVMHost::createPOCSAGNetwork()
 
 bool CMMDVMHost::createFMNetwork()
 {
+	std::string format         = m_conf.getFMNetworkFormat();
 	std::string gatewayAddress = m_conf.getFMGatewayAddress();
 	unsigned int gatewayPort   = m_conf.getFMGatewayPort();
 	std::string localAddress   = m_conf.getFMLocalAddress();
@@ -1805,6 +1806,7 @@ bool CMMDVMHost::createFMNetwork()
 	bool debug                 = m_conf.getFMNetworkDebug();
 
 	LogInfo("FM Network Parameters");
+	LogInfo("    Format: %s", format.c_str());
 	LogInfo("    Gateway Address: %s", gatewayAddress.c_str());
 	LogInfo("    Gateway Port: %u", gatewayPort);
 	LogInfo("    Local Address: %s", localAddress.c_str());
@@ -1812,7 +1814,7 @@ bool CMMDVMHost::createFMNetwork()
 	LogInfo("    Sample Rate: %u", sampleRate);
 	LogInfo("    Mode Hang: %us", m_fmNetModeHang);
 
-	m_fmNetwork = new CFMNetwork(localAddress, localPort, gatewayAddress, gatewayPort, sampleRate, debug);
+	m_fmNetwork = new CFMNetwork(format, localAddress, localPort, gatewayAddress, gatewayPort, sampleRate, debug);
 
 	bool ret = m_fmNetwork->open();
 	if (!ret) {
diff --git a/Version.h b/Version.h
index 7365a93..028594f 100644
--- a/Version.h
+++ b/Version.h
@@ -19,6 +19,6 @@
 #if !defined(VERSION_H)
 #define	VERSION_H
 
-const char* VERSION = "20210312";
+const char* VERSION = "20210314";
 
 #endif

From 75e8e95aad0945572d7995e8e51eb80b394f71a0 Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Sun, 14 Mar 2021 14:59:34 +0000
Subject: [PATCH 05/23] Add FM network audio gain and optional pre- and
 de-emphasis.

---
 Conf.cpp      | 42 ++++++++++++++++++++++++++++++----
 Conf.h        | 12 ++++++++--
 FMControl.cpp | 63 +++++++++++++++++++++++++++++++--------------------
 FMControl.h   | 12 ++++++----
 FMNetwork.cpp | 32 +++++++++++++-------------
 FMNetwork.h   | 30 ++++++++++++------------
 MMDVM.ini     |  6 ++++-
 MMDVMHost.cpp | 24 +++++++++++++++-----
 8 files changed, 147 insertions(+), 74 deletions(-)

diff --git a/Conf.cpp b/Conf.cpp
index d69d297..83d22f4 100644
--- a/Conf.cpp
+++ b/Conf.cpp
@@ -283,12 +283,16 @@ m_pocsagLocalPort(0U),
 m_pocsagNetworkModeHang(3U),
 m_pocsagNetworkDebug(false),
 m_fmNetworkEnabled(false),
-m_fmNetworkFormat("MMDVM"),
+m_fmNetworkProtocol("MMDVM"),
 m_fmGatewayAddress(),
 m_fmGatewayPort(0U),
 m_fmLocalAddress(),
 m_fmLocalPort(0U),
 m_fmSampleRate(8000U),
+m_fmPreEmphasis(true),
+m_fmDeEmphasis(true),
+m_fmTXAudioGain(1.0F),
+m_fmRXAudioGain(1.0F),
 m_fmNetworkModeHang(3U),
 m_fmNetworkDebug(false),
 m_ax25NetworkEnabled(false),
@@ -999,8 +1003,8 @@ bool CConf::read()
 		} else if (section == SECTION_FM_NETWORK) {
 			if (::strcmp(key, "Enable") == 0)
 				m_fmNetworkEnabled = ::atoi(value) == 1;
-			else if (::strcmp(key, "Format") == 0)
-				m_fmNetworkFormat = value;
+			else if (::strcmp(key, "Protocol") == 0)
+				m_fmNetworkProtocol = value;
 			else if (::strcmp(key, "LocalAddress") == 0)
 				m_fmLocalAddress = value;
 			else if (::strcmp(key, "LocalPort") == 0)
@@ -1011,6 +1015,14 @@ bool CConf::read()
 				m_fmGatewayPort = (unsigned int)::atoi(value);
 			else if (::strcmp(key, "SampleRate") == 0)
 				m_fmSampleRate = (unsigned int)::atoi(value);
+			else if (::strcmp(key, "PreEmphasis") == 0)
+				m_fmPreEmphasis = ::atoi(value) == 1;
+			else if (::strcmp(key, "DeEmphasis") == 0)
+				m_fmDeEmphasis = ::atoi(value) == 1;
+			else if (::strcmp(key, "TXAudioGain") == 0)
+				m_fmTXAudioGain = float(::atof(value));
+			else if (::strcmp(key, "RXAudioGain") == 0)
+				m_fmRXAudioGain = float(::atof(value));
 			else if (::strcmp(key, "ModeHang") == 0)
 				m_fmNetworkModeHang = (unsigned int)::atoi(value);
 			else if (::strcmp(key, "Debug") == 0)
@@ -2200,9 +2212,9 @@ bool CConf::getFMNetworkEnabled() const
 	return m_fmNetworkEnabled;
 }
 
-std::string CConf::getFMNetworkFormat() const
+std::string CConf::getFMNetworkProtocol() const
 {
-	return m_fmNetworkFormat;
+	return m_fmNetworkProtocol;
 }
 
 std::string CConf::getFMGatewayAddress() const
@@ -2230,6 +2242,26 @@ unsigned int CConf::getFMSampleRate() const
 	return m_fmSampleRate;
 }
 
+bool CConf::getFMPreEmphasis() const
+{
+	return m_fmPreEmphasis;
+}
+
+bool CConf::getFMDeEmphasis() const
+{
+	return m_fmDeEmphasis;
+}
+
+float CConf::getFMTXAudioGain() const
+{
+	return m_fmTXAudioGain;
+}
+
+float CConf::getFMRXAudioGain() const
+{
+	return m_fmRXAudioGain;
+}
+
 unsigned int CConf::getFMNetworkModeHang() const
 {
 	return m_fmNetworkModeHang;
diff --git a/Conf.h b/Conf.h
index 7a5c56a..aad1155 100644
--- a/Conf.h
+++ b/Conf.h
@@ -296,12 +296,16 @@ public:
 
   // The FM Network section
   bool         getFMNetworkEnabled() const;
-  std::string  getFMNetworkFormat() const;
+  std::string  getFMNetworkProtocol() const;
   std::string  getFMGatewayAddress() const;
   unsigned int getFMGatewayPort() const;
   std::string  getFMLocalAddress() const;
   unsigned int getFMLocalPort() const;
   unsigned int getFMSampleRate() const;
+  bool         getFMPreEmphasis() const;
+  bool         getFMDeEmphasis() const;
+  float        getFMTXAudioGain() const;
+  float        getFMRXAudioGain() const;
   unsigned int getFMNetworkModeHang() const;
   bool         getFMNetworkDebug() const;
 
@@ -604,12 +608,16 @@ private:
   bool         m_pocsagNetworkDebug;
 
   bool         m_fmNetworkEnabled;
-  std::string  m_fmNetworkFormat;
+  std::string  m_fmNetworkProtocol;
   std::string  m_fmGatewayAddress;
   unsigned int m_fmGatewayPort;
   std::string  m_fmLocalAddress;
   unsigned int m_fmLocalPort;
   unsigned int m_fmSampleRate;
+  bool         m_fmPreEmphasis;
+  bool         m_fmDeEmphasis;
+  float        m_fmTXAudioGain;
+  float        m_fmRXAudioGain;
   unsigned int m_fmNetworkModeHang;
   bool         m_fmNetworkDebug;
 
diff --git a/FMControl.cpp b/FMControl.cpp
index 076cbc9..c44c324 100644
--- a/FMControl.cpp
+++ b/FMControl.cpp
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -31,20 +31,27 @@ const float        PREEMPHASIS_GAIN_DB = 0.0F;  // Audio gain  adjustment
 const float        FILTER_GAIN_DB      = 2.0F;  // Audio gain  adjustment
 const unsigned int FM_MASK             = 0x00000FFFU;
 
-CFMControl::CFMControl(CFMNetwork* network) :
+CFMControl::CFMControl(CFMNetwork* network, float txAudioGain, float rxAudioGain, bool preEmphasisOn, bool deEmphasisOn) :
 m_network(network),
+m_txAudioGain(txAudioGain),
+m_rxAudioGain(rxAudioGain),
+m_preEmphasisOn(preEmphasisOn),
+m_deEmphasisOn(deEmphasisOn),
 m_enabled(false),
 m_incomingRFAudio(1600U, "Incoming RF FM Audio"),
-m_preemphasis (NULL),
-m_deemphasis  (NULL),
+m_preEmphasis(NULL),
+m_deEmphasis(NULL),
 m_filterStage1(NULL),
 m_filterStage2(NULL),
 m_filterStage3(NULL)
 {
-    m_preemphasis  = new CIIRDirectForm1Filter(8.315375384336983F,-7.03334621603483F,0.0F,1.0F,0.282029168302153F,0.0F, PREEMPHASIS_GAIN_DB);
-    m_deemphasis   = new CIIRDirectForm1Filter(0.07708787090460224F,0.07708787090460224F,0.0F,1.0F,-0.8458242581907955F,0.0F, DEEMPHASIS_GAIN_DB);
+    assert(txAudioGain > 0.0F);
+    assert(rxAudioGain > 0.0F);
 
-    //cheby type 1 0.2dB cheby type 1 3rd order 300-2700Hz fs=8000
+    m_preEmphasis  = new CIIRDirectForm1Filter(8.315375384336983F, -7.03334621603483F,0.0F,1.0F, 0.282029168302153F,0.0F, PREEMPHASIS_GAIN_DB);
+    m_deEmphasis   = new CIIRDirectForm1Filter(0.07708787090460224F, 0.07708787090460224F,0.0F, 1.0F, -0.8458242581907955F,0.0F, DEEMPHASIS_GAIN_DB);
+
+    // Chebyshev type 1 0.2dB cheby type 1 3rd order 300-2700Hz fs=8000
     m_filterStage1 = new CIIRDirectForm1Filter(0.29495028f, 0.0f, -0.29495028f, 1.0f, -0.61384624f, -0.057158668f, FILTER_GAIN_DB);
     m_filterStage2 = new CIIRDirectForm1Filter(1.0f, 2.0f, 1.0f, 1.0f, 0.9946123f, 0.6050482f, FILTER_GAIN_DB);
     m_filterStage3 = new CIIRDirectForm1Filter(1.0f, -2.0f, 1.0f, 1.0f, -1.8414584f, 0.8804949f, FILTER_GAIN_DB);
@@ -52,8 +59,8 @@ m_filterStage3(NULL)
 
 CFMControl::~CFMControl()
 {
-    delete m_preemphasis ;
-    delete m_deemphasis  ;
+    delete m_preEmphasis;
+    delete m_deEmphasis;
 
     delete m_filterStage1;
     delete m_filterStage2;
@@ -79,42 +86,45 @@ bool CFMControl::writeModem(const unsigned char* data, unsigned int length)
 
     m_incomingRFAudio.addData(data + 1U, length - 1U);
     unsigned int bufferLength = m_incomingRFAudio.dataSize();
-    if (bufferLength > 240U)    //160 samples 12-bit
-        bufferLength = 240U;    //160 samples 12-bit
+    if (bufferLength > 240U)    // 160 samples 12-bit
+        bufferLength = 240U;    // 160 samples 12-bit
 
     if (bufferLength >= 3U) {
-        bufferLength = bufferLength - bufferLength % 3U; //round down to nearest multiple of 3
-        unsigned char bufferData[240U];     //160 samples 12-bit       
+        bufferLength = bufferLength - bufferLength % 3U;    // Round down to nearest multiple of 3
+        unsigned char bufferData[240U];                     // 160 samples 12-bit       
         m_incomingRFAudio.getData(bufferData, bufferLength);
 
         unsigned int pack = 0U;
         unsigned char* packPointer = (unsigned char*)&pack;
-        float out[160U];  //160 samples 12-bit
+        float out[160U];                                    // 160 samples 12-bit
         unsigned int nOut = 0U;
         short unpackedSamples[2U];
 
         for (unsigned int i = 0U; i < bufferLength; i += 3U) {
-            //extract unsigned 12 bit unsigned sample pairs packed into 3 bytes to 16 bit signed
-            packPointer[0U] = bufferData[i];
+            // Extract unsigned 12 bit unsigned sample pairs packed into 3 bytes to 16 bit signed
+            packPointer[0U] = bufferData[i + 0U];
             packPointer[1U] = bufferData[i + 1U];
             packPointer[2U] = bufferData[i + 2U];
+
             unpackedSamples[1U] = short(int(pack & FM_MASK) - 2048);
             unpackedSamples[0U] = short(int(pack >> 12 & FM_MASK) - 2048); // 
 
-            //process unpacked sample pair
+            // Process unpacked sample pair
             for (unsigned char j = 0U; j < 2U; j++) {
                 // Convert to float (-1.0 to +1.0)
-                float sampleFloat = float(unpackedSamples[j]) / 2048.0F;
+                float sampleFloat = (float(unpackedSamples[j]) * m_rxAudioGain) / 2048.0F;
 
                 // De-emphasise and remove CTCSS
-                sampleFloat = m_deemphasis->filter(sampleFloat);
+                if (m_deEmphasisOn)
+                    sampleFloat = m_deEmphasis->filter(sampleFloat);
+
                 out[nOut++] = m_filterStage3->filter(m_filterStage2->filter(m_filterStage1->filter(sampleFloat)));
             }
         }
 
 #if defined(DUMP_RF_AUDIO)
         FILE * audiofile = fopen("./audiodump.bin", "ab");
-        if(audiofile != NULL) {
+        if (audiofile != NULL) {
             fwrite(out, sizeof(float), nOut, audiofile);
             fclose(audiofile);
         }
@@ -133,8 +143,8 @@ unsigned int CFMControl::readModem(unsigned char* data, unsigned int space)
     if (m_network == NULL)
         return 0U;
 
-    if (space > 240U) //160 samples 12-bit
-        space = 240U; //160 samples 12-bit
+    if (space > 240U)           // 160 samples 12-bit
+        space = 240U;           // 160 samples 12-bit
 
     float netData[160U]; // Modem can handle up to 160 samples at a time
     unsigned int length = m_network->read(netData, 160U);  //160 samples 12-bit
@@ -146,14 +156,17 @@ unsigned int CFMControl::readModem(unsigned char* data, unsigned int space)
     unsigned int nData = 0U;
 
     for (unsigned int i = 0; i < length; i++) {
+        float sampleFloat = netData[i] * m_txAudioGain;
+
         // Pre-emphasis
-        float sampleFloat = m_preemphasis->filter(netData[i]);
+        if (m_preEmphasisOn)
+            sampleFloat = m_preEmphasis->filter(sampleFloat);
 
         // Convert float to 12-bit samples (0 to 4095)
         unsigned int sample12bit = (unsigned int)((sampleFloat + 1.0F) * 2048.0F + 0.5F);
 
-        // pack 2 samples onto 3 bytes
-        if((i & 1U) == 0) {
+        // Pack 2 samples into 3 bytes
+        if ((i & 1U) == 0) {
             pack = 0U;
             pack = sample12bit << 12;
         } else {
diff --git a/FMControl.h b/FMControl.h
index ac2142e..9344f77 100644
--- a/FMControl.h
+++ b/FMControl.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -30,7 +30,7 @@
 
 class CFMControl {
 public:
-	CFMControl(CFMNetwork* network);
+	CFMControl(CFMNetwork* network, float txAudioGain, float rxAudioGain, bool preEmphasisOn, bool deEmphasisOn);
 	~CFMControl();
 
 	bool writeModem(const unsigned char* data, unsigned int length);
@@ -43,10 +43,14 @@ public:
 
 private:
 	CFMNetwork* m_network;
+	float       m_txAudioGain;
+	float       m_rxAudioGain;
+	bool        m_preEmphasisOn;
+	bool        m_deEmphasisOn;
     bool        m_enabled;
 	CRingBuffer<unsigned char> m_incomingRFAudio;
-	CIIRDirectForm1Filter* m_preemphasis;
-	CIIRDirectForm1Filter* m_deemphasis;
+	CIIRDirectForm1Filter* m_preEmphasis;
+	CIIRDirectForm1Filter* m_deEmphasis;
 	CIIRDirectForm1Filter* m_filterStage1;
 	CIIRDirectForm1Filter* m_filterStage2;
 	CIIRDirectForm1Filter* m_filterStage3;
diff --git a/FMNetwork.cpp b/FMNetwork.cpp
index d9aa0e5..85947c9 100644
--- a/FMNetwork.cpp
+++ b/FMNetwork.cpp
@@ -27,8 +27,8 @@
 
 const unsigned int BUFFER_LENGTH = 500U;
 
-CFMNetwork::CFMNetwork(const std::string& format, const std::string& localAddress, unsigned int localPort, const std::string& gatewayAddress, unsigned int gatewayPort, unsigned int sampleRate, bool debug) :
-m_format(FMF_MMDVM),
+CFMNetwork::CFMNetwork(const std::string& protocol, const std::string& localAddress, unsigned int localPort, const std::string& gatewayAddress, unsigned int gatewayPort, unsigned int sampleRate, bool debug) :
+m_protocol(FMNP_MMDVM),
 m_socket(localAddress, localPort),
 m_addr(),
 m_addrLen(0U),
@@ -46,8 +46,8 @@ m_seqNo(0U)
 	if (CUDPSocket::lookup(gatewayAddress, gatewayPort, m_addr, m_addrLen) != 0)
 		m_addrLen = 0U;
 
-	if (format == "USRP")
-		m_format = FMF_USRP;
+	if (protocol == "USRP")
+		m_protocol = FMNP_USRP;
 
 #if !defined(_WIN32) && !defined(_WIN64)
 	int error;
@@ -116,7 +116,7 @@ bool CFMNetwork::writeData(float* data, unsigned int nSamples)
 
 	unsigned int length = 0U;
 
-	if (m_format == FMF_USRP) {
+	if (m_protocol == FMNP_USRP) {
 		buffer[length++] = 'U';
 		buffer[length++] = 'S';
 		buffer[length++] = 'R';
@@ -187,7 +187,7 @@ bool CFMNetwork::writeData(float* data, unsigned int nSamples)
 
 bool CFMNetwork::writeEOT()
 {
-	if (m_format == FMF_MMDVM) {
+	if (m_protocol == FMNP_MMDVM) {
 		unsigned char buffer[10U];
 		::memset(buffer, 0x00U, 10U);
 
@@ -220,11 +220,11 @@ void CFMNetwork::clock(unsigned int ms)
 	if (length <= 0)
 		return;
 
-	// Check if the data is for us					// does not accept data from USRP 
-	//if (!CUDPSocket::match(addr, m_addr)) {
-	//	LogMessage("FM packet received from an invalid source");
-	//	return;
-	//}
+	// Check if the data is for us
+	if (!CUDPSocket::match(addr, m_addr)) {
+		LogMessage("FM packet received from an invalid source");
+		return;
+	}
 
 	if (!m_enabled)
 		return;
@@ -232,7 +232,7 @@ void CFMNetwork::clock(unsigned int ms)
 	if (m_debug)
 		CUtils::dump(1U, "FM Network Data Received", buffer, length);
 
-	if (m_format == FMF_USRP) {
+	if (m_protocol == FMNP_USRP) {
 		// Invalid packet type?
 		if (::memcmp(buffer, "USRP", 4U) != 0)
 			return;
@@ -304,9 +304,9 @@ unsigned int CFMNetwork::read(float* data, unsigned int nSamples)
 	} else {
 #endif
 		for (unsigned int i = 0U; i < nSamples; i++) {
-			 short val = ((buffer[i * 2U + 0U] & 0xFFU) << 0) +	// Changing audio format from  U16BE to S16LE
-			             ((buffer[i * 2U + 1U] & 0xFFU) << 8);	// Changing audio format from  U16BE to S16LE
-			data[i] = (float(val)  / 65536.0F);	// Changing audio format from  U16BE to S16LE
+			short val = ((buffer[i * 2U + 0U] & 0xFFU) << 0) +
+						((buffer[i * 2U + 1U] & 0xFFU) << 8);
+			data[i] = float(val) / 65536.0F;
 		}
 
 		return nSamples;
@@ -347,7 +347,7 @@ void CFMNetwork::enable(bool enabled)
 
 void CFMNetwork::writePoll()
 {
-	if (m_format == FMF_MMDVM) {
+	if (m_protocol == FMNP_MMDVM) {
 		unsigned char buffer[3U];
 
 		buffer[0U] = 'F';
diff --git a/FMNetwork.h b/FMNetwork.h
index d7b1ff7..90f4225 100644
--- a/FMNetwork.h
+++ b/FMNetwork.h
@@ -30,14 +30,14 @@
 #include <cstdint>
 #include <string>
 
-enum FM_FORMAT {
-	FMF_MMDVM,
-	FMF_USRP
+enum FM_NETWORK_PROTOCOL {
+	FMNP_MMDVM,
+	FMNP_USRP
 };
 
 class CFMNetwork {
 public:
-	CFMNetwork(const std::string& format, const std::string& myAddress, unsigned int myPort, const std::string& gatewayAddress, unsigned int gatewayPort, unsigned int sampleRate, bool debug);
+	CFMNetwork(const std::string& protocol, const std::string& myAddress, unsigned int myPort, const std::string& gatewayAddress, unsigned int gatewayPort, unsigned int sampleRate, bool debug);
 	~CFMNetwork();
 
 	bool open();
@@ -57,19 +57,19 @@ public:
 	void clock(unsigned int ms);
 
 private:
-	FM_FORMAT        m_format;
-	CUDPSocket       m_socket;
-	sockaddr_storage m_addr;
-	unsigned int     m_addrLen;
-	unsigned int     m_sampleRate;
-	bool             m_debug;
-	bool             m_enabled;
+	FM_NETWORK_PROTOCOL m_protocol;
+	CUDPSocket          m_socket;
+	sockaddr_storage    m_addr;
+	unsigned int        m_addrLen;
+	unsigned int        m_sampleRate;
+	bool                m_debug;
+	bool                m_enabled;
 	CRingBuffer<unsigned char> m_buffer;
-	CTimer           m_pollTimer;
-	unsigned int     m_seqNo;
+	CTimer              m_pollTimer;
+	unsigned int        m_seqNo;
 #if !defined(_WIN32) && !defined(_WIN64)
-	SRC_STATE*       m_incoming;
-	SRC_STATE*       m_outgoing;
+	SRC_STATE*          m_incoming;
+	SRC_STATE*          m_outgoing;
 #endif
 
 	void writePoll();
diff --git a/MMDVM.ini b/MMDVM.ini
index 255c12d..be1dbcf 100644
--- a/MMDVM.ini
+++ b/MMDVM.ini
@@ -276,12 +276,16 @@ Debug=0
 [FM Network]
 Enable=1
 # Values are MMDVM and USRP
-Format=USRP
+Protocol=USRP
 LocalAddress=127.0.0.1
 LocalPort=3810
 GatewayAddress=127.0.0.1
 GatewayPort=4810
 SampleRate=8000
+PreEmphasis=1
+DeEmphasis=1
+TXAudioGain=1.0
+RXAudioGain=1.0
 # ModeHang=3
 Debug=0
 
diff --git a/MMDVMHost.cpp b/MMDVMHost.cpp
index b78d7e9..2f51e69 100644
--- a/MMDVMHost.cpp
+++ b/MMDVMHost.cpp
@@ -681,15 +681,19 @@ int CMMDVMHost::run()
 	}
 
 	if (m_fmEnabled) {
-		m_fmRFModeHang = m_conf.getFMModeHang();
+		bool preEmphasis  = m_conf.getFMPreEmphasis();
+		bool deEmphasis   = m_conf.getFMDeEmphasis();
+		float txAudioGain = m_conf.getFMTXAudioGain();
+		float rxAudioGain = m_conf.getFMRXAudioGain();
+		m_fmRFModeHang    = m_conf.getFMModeHang();
 
-		m_fm = new CFMControl(m_fmNetwork);
+		m_fm = new CFMControl(m_fmNetwork, txAudioGain, rxAudioGain, preEmphasis, deEmphasis);
 	}
 
 	bool remoteControlEnabled = m_conf.getRemoteControlEnabled();
 	if (remoteControlEnabled) {
 		std::string address = m_conf.getRemoteControlAddress();
-		unsigned int port = m_conf.getRemoteControlPort();
+		unsigned int port   = m_conf.getRemoteControlPort();
 
 		LogInfo("Remote Control Parameters");
 		LogInfo("    Address: %s", address.c_str());
@@ -1796,25 +1800,33 @@ bool CMMDVMHost::createPOCSAGNetwork()
 
 bool CMMDVMHost::createFMNetwork()
 {
-	std::string format         = m_conf.getFMNetworkFormat();
+	std::string protocol       = m_conf.getFMNetworkProtocol();
 	std::string gatewayAddress = m_conf.getFMGatewayAddress();
 	unsigned int gatewayPort   = m_conf.getFMGatewayPort();
 	std::string localAddress   = m_conf.getFMLocalAddress();
 	unsigned int localPort     = m_conf.getFMLocalPort();
 	unsigned int sampleRate    = m_conf.getFMSampleRate();
+	bool preEmphasis           = m_conf.getFMPreEmphasis();
+	bool deEmphasis            = m_conf.getFMDeEmphasis();
+	float txAudioGain          = m_conf.getFMTXAudioGain();
+	float rxAudioGain          = m_conf.getFMRXAudioGain();
 	m_fmNetModeHang            = m_conf.getFMNetworkModeHang();
 	bool debug                 = m_conf.getFMNetworkDebug();
 
 	LogInfo("FM Network Parameters");
-	LogInfo("    Format: %s", format.c_str());
+	LogInfo("    Protocol: %s", protocol.c_str());
 	LogInfo("    Gateway Address: %s", gatewayAddress.c_str());
 	LogInfo("    Gateway Port: %u", gatewayPort);
 	LogInfo("    Local Address: %s", localAddress.c_str());
 	LogInfo("    Local Port: %u", localPort);
 	LogInfo("    Sample Rate: %u", sampleRate);
+	LogInfo("    Pre-Emphasis: %s", preEmphasis ? "yes" : "no");
+	LogInfo("    De-Emphasis: %s", deEmphasis ? "yes" : "no");
+	LogInfo("    TX Audio Gain: %.2f", txAudioGain);
+	LogInfo("    RX Audio Gain: %.2f", rxAudioGain);
 	LogInfo("    Mode Hang: %us", m_fmNetModeHang);
 
-	m_fmNetwork = new CFMNetwork(format, localAddress, localPort, gatewayAddress, gatewayPort, sampleRate, debug);
+	m_fmNetwork = new CFMNetwork(protocol, localAddress, localPort, gatewayAddress, gatewayPort, sampleRate, debug);
 
 	bool ret = m_fmNetwork->open();
 	if (!ret) {

From d0ccc0ee6105a3956cf04004e31389953488961b Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Sun, 14 Mar 2021 16:24:48 +0000
Subject: [PATCH 06/23] Try and fix a crash.

---
 FMControl.cpp |  2 +-
 FMNetwork.cpp | 12 +++++++++---
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/FMControl.cpp b/FMControl.cpp
index c44c324..7f1ff07 100644
--- a/FMControl.cpp
+++ b/FMControl.cpp
@@ -147,7 +147,7 @@ unsigned int CFMControl::readModem(unsigned char* data, unsigned int space)
         space = 240U;           // 160 samples 12-bit
 
     float netData[160U]; // Modem can handle up to 160 samples at a time
-    unsigned int length = m_network->read(netData, 160U);  //160 samples 12-bit
+    unsigned int length = m_network->read(netData, 160U);  // 160 samples 12-bit
     if (length == 0U)
         return 0U;
 
diff --git a/FMNetwork.cpp b/FMNetwork.cpp
index 85947c9..947ceb8 100644
--- a/FMNetwork.cpp
+++ b/FMNetwork.cpp
@@ -25,7 +25,7 @@
 #include <cassert>
 #include <cstring>
 
-const unsigned int BUFFER_LENGTH = 500U;
+const unsigned int BUFFER_LENGTH = 1500U;
 
 CFMNetwork::CFMNetwork(const std::string& protocol, const std::string& localAddress, unsigned int localPort, const std::string& gatewayAddress, unsigned int gatewayPort, unsigned int sampleRate, bool debug) :
 m_protocol(FMNP_MMDVM),
@@ -111,8 +111,8 @@ bool CFMNetwork::writeData(float* data, unsigned int nSamples)
 	}
 #endif
 
-	unsigned char buffer[2000U];
-	::memset(buffer, 0x00U, 2000U);
+	unsigned char buffer[1500U];
+	::memset(buffer, 0x00U, 1500U);
 
 	unsigned int length = 0U;
 
@@ -237,6 +237,9 @@ void CFMNetwork::clock(unsigned int ms)
 		if (::memcmp(buffer, "USRP", 4U) != 0)
 			return;
 
+		if (length < 32)
+			return;
+
 		// The type is a big-endian 4-byte integer
 		unsigned int type = (buffer[20U] << 24) +
 							(buffer[21U] << 16) +
@@ -254,6 +257,9 @@ void CFMNetwork::clock(unsigned int ms)
 		if (::memcmp(buffer, "FMD", 3U) != 0)
 			return;
 
+		if (length < 3)
+			return;
+
 		m_buffer.addData(buffer + 3U, length - 3U);
 	}
 }

From 42570c905d9017f8aa876d07a909fbea60c338ef Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Sun, 14 Mar 2021 19:04:54 +0000
Subject: [PATCH 07/23] Handle updated M17 modem serial data.

---
 Modem.cpp | 48 +++++++++++++++++++++++++++++++++++-------------
 1 file changed, 35 insertions(+), 13 deletions(-)

diff --git a/Modem.cpp b/Modem.cpp
index d6ed93f..6af10d2 100644
--- a/Modem.cpp
+++ b/Modem.cpp
@@ -74,9 +74,10 @@ const unsigned char MMDVM_P25_LOST    = 0x32U;
 const unsigned char MMDVM_NXDN_DATA   = 0x40U;
 const unsigned char MMDVM_NXDN_LOST   = 0x41U;
 
-const unsigned char MMDVM_M17_HEADER  = 0x45U;
-const unsigned char MMDVM_M17_DATA    = 0x46U;
-const unsigned char MMDVM_M17_LOST    = 0x47U;
+const unsigned char MMDVM_M17_LINK_SETUP = 0x45U;
+const unsigned char MMDVM_M17_STREAM     = 0x46U;
+const unsigned char MMDVM_M17_PACKET     = 0x47U;
+const unsigned char MMDVM_M17_LOST       = 0x48U;
 
 const unsigned char MMDVM_POCSAG_DATA = 0x50U;
 
@@ -648,9 +649,9 @@ void CModem::clock(unsigned int ms)
 			}
 			break;
 
-			case MMDVM_M17_HEADER: {
+			case MMDVM_M17_LINK_SETUP: {
 				if (m_trace)
-					CUtils::dump(1U, "RX M17 Header", m_buffer, m_length);
+					CUtils::dump(1U, "RX M17 Link Setup", m_buffer, m_length);
 
 				unsigned char data = m_length - 2U;
 				m_rxM17Data.addData(&data, 1U);
@@ -662,9 +663,23 @@ void CModem::clock(unsigned int ms)
 			}
 			break;
 
-			case MMDVM_M17_DATA: {
+			case MMDVM_M17_STREAM: {
 				if (m_trace)
-					CUtils::dump(1U, "RX M17 Data", m_buffer, m_length);
+					CUtils::dump(1U, "RX M17 Stream Data", m_buffer, m_length);
+
+				unsigned char data = m_length - 2U;
+				m_rxM17Data.addData(&data, 1U);
+
+				data = TAG_DATA;
+				m_rxM17Data.addData(&data, 1U);
+
+				m_rxM17Data.addData(m_buffer + 3U, m_length - 3U);
+			}
+			break;
+
+			case MMDVM_M17_PACKET: {
+				if (m_trace)
+					CUtils::dump(1U, "RX M17 Packet Data", m_buffer, m_length);
 
 				unsigned char data = m_length - 2U;
 				m_rxM17Data.addData(&data, 1U);
@@ -1019,10 +1034,17 @@ void CModem::clock(unsigned int ms)
 		m_txM17Data.getData(m_buffer, len);
 
 		if (m_trace) {
-			if (m_buffer[2U] == MMDVM_M17_HEADER)
-				CUtils::dump(1U, "TX M17 Header", m_buffer, len);
-			else
-				CUtils::dump(1U, "TX M17 Data", m_buffer, len);
+			switch (m_buffer[2U]) {
+			case MMDVM_M17_LINK_SETUP:
+				CUtils::dump(1U, "TX M17 Link Setup", m_buffer, len);
+				break;
+			case MMDVM_M17_STREAM:
+				CUtils::dump(1U, "TX M17 Stream Data", m_buffer, len);
+				break;
+			case MMDVM_M17_PACKET:
+				CUtils::dump(1U, "TX M17 Packet Data", m_buffer, len);
+				break;
+			}
 		}
 
 		int ret = m_port->write(m_buffer, len);
@@ -1487,9 +1509,9 @@ bool CModem::writeM17Data(const unsigned char* data, unsigned int length)
 	buffer[1U] = length + 2U;
 
 	if (data[0U] == TAG_HEADER)
-		buffer[2U] = MMDVM_M17_HEADER;
+		buffer[2U] = MMDVM_M17_LINK_SETUP;
 	else
-		buffer[2U] = MMDVM_M17_DATA;
+		buffer[2U] = MMDVM_M17_STREAM;
 
 	::memcpy(buffer + 3U, data + 1U, length - 1U);
 

From a3e4a250bd51d36a479c735e87e009a47a2f9fb5 Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Sun, 14 Mar 2021 21:00:47 +0000
Subject: [PATCH 08/23] Make the Null Controller respond properly.

---
 NullController.cpp | 143 ++++++++++++++++++++++++++++++++++++++++++++-
 NullController.h   |   7 +++
 2 files changed, 147 insertions(+), 3 deletions(-)

diff --git a/NullController.cpp b/NullController.cpp
index fb48a04..edfeffe 100644
--- a/NullController.cpp
+++ b/NullController.cpp
@@ -18,7 +18,31 @@
 
 #include "NullController.h"
 
-CNullController::CNullController()
+#include <cstdio>
+#include <cassert>
+
+const unsigned char MMDVM_FRAME_START = 0xE0U;
+
+const unsigned char MMDVM_GET_VERSION = 0x00U;
+const unsigned char MMDVM_GET_STATUS  = 0x01U;
+const unsigned char MMDVM_SET_CONFIG  = 0x02U;
+const unsigned char MMDVM_SET_MODE    = 0x03U;
+const unsigned char MMDVM_SET_FREQ    = 0x04U;
+
+const unsigned char MMDVM_FM_PARAMS1 = 0x60U;
+const unsigned char MMDVM_FM_PARAMS2 = 0x61U;
+const unsigned char MMDVM_FM_PARAMS3 = 0x62U;
+const unsigned char MMDVM_FM_PARAMS4 = 0x63U;
+
+const unsigned char MMDVM_ACK = 0x70U;
+const unsigned char MMDVM_NAK = 0x7FU;
+
+const unsigned char PROTOCOL_VERSION = 2U; 
+
+const char* HARDWARE = "Null Modem Controller";
+
+CNullController::CNullController() :
+m_buffer(200U, "Null Controller Buffer")
 {
 }
 
@@ -33,15 +57,128 @@ bool CNullController::open()
 
 int CNullController::read(unsigned char* buffer, unsigned int length)
 {
-	return 0;
+	unsigned int dataSize = m_buffer.dataSize();
+	if (dataSize == 0U)
+		return 0;
+
+	if (length > dataSize)
+		length = dataSize;
+
+	m_buffer.getData(buffer, length);
+
+	return int(length);
 }
 
 int CNullController::write(const unsigned char* buffer, unsigned int length)
 {
-	return length;
+	switch (buffer[2U]) {
+	case MMDVM_GET_VERSION:
+		writeVersion();
+		break;
+	case MMDVM_GET_STATUS:
+		writeStatus();
+		break;
+	case MMDVM_SET_CONFIG:
+	case MMDVM_SET_FREQ:
+	case MMDVM_SET_MODE:
+	case MMDVM_FM_PARAMS1:
+	case MMDVM_FM_PARAMS2:
+	case MMDVM_FM_PARAMS3:
+	case MMDVM_FM_PARAMS4:
+		writeAck(buffer[2U]);
+		break;
+	default:
+		break;
+	}
+
+	return int(length);
 }
 
 
 void CNullController::close()
 {
 }
+
+void CNullController::writeVersion()
+{
+	unsigned char reply[200U];
+
+	reply[0U] = MMDVM_FRAME_START;
+	reply[1U] = 0U;
+	reply[2U] = MMDVM_GET_VERSION;
+
+	reply[3U] = PROTOCOL_VERSION;
+
+	// Return two bytes of mode capabilities
+	reply[4U] = 0xFFU;
+	reply[5U] = 0xFFU;
+
+	// CPU type/manufacturer. 0=Atmel ARM, 1=NXP ARM, 2=St-Micro ARM
+	reply[6U] = 2U;
+
+	// Reserve 16 bytes for the UDID
+	::memset(reply + 7U, 0x00U, 16U);
+
+	uint8_t count = 23U;
+	for (uint8_t i = 0U; HARDWARE[i] != 0x00U; i++, count++)
+		reply[count] = HARDWARE[i];
+
+	reply[1U] = count;
+
+	m_buffer.addData(reply, count);
+}
+
+void CNullController::writeStatus()
+{
+	unsigned char reply[30U];
+
+	// Send all sorts of interesting internal values
+	reply[0U] = MMDVM_FRAME_START;
+	reply[1U] = 20U;
+	reply[2U] = MMDVM_GET_STATUS;
+
+	reply[3U] = 0U;
+
+	reply[4U] = 0x00U;
+
+	reply[5U] = 0x00U;
+
+	reply[6U] = 20U;
+
+	reply[7U] = 20U;
+	reply[8U] = 20U;
+
+	reply[9U] = 20U;
+
+	reply[10U] = 20U;
+
+	reply[11U] = 20U;
+
+	reply[12U] = 20U;
+
+	reply[13U] = 20U;
+
+	reply[14U] = 0x00U;
+	reply[15U] = 0x00U;
+
+	reply[16U] = 20U;
+
+	reply[17U] = 20U;
+
+	reply[18U] = 0x00U;
+	reply[19U] = 0x00U;
+
+	m_buffer.addData(reply, 20U);
+}
+
+void CNullController::writeAck(unsigned char type)
+{
+	unsigned char reply[4U];
+
+	reply[0U] = MMDVM_FRAME_START;
+	reply[1U] = 4U;
+	reply[2U] = MMDVM_ACK;
+	reply[3U] = type;
+
+	m_buffer.addData(reply, 4U);
+}
diff --git a/NullController.h b/NullController.h
index bbf0681..2dad99b 100644
--- a/NullController.h
+++ b/NullController.h
@@ -21,6 +21,8 @@
 
 #include "ModemPort.h"
 
+#include "RingBuffer.h"
+
 class CNullController : public IModemPort {
 public:
 	CNullController();
@@ -35,6 +37,11 @@ public:
 	virtual void close();
 
 private:
+	CRingBuffer<unsigned char> m_buffer;
+
+	void writeVersion();
+	void writeStatus();
+	void writeAck(unsigned char type);
 };
 
 #endif

From 95cb575a2e7a535ae3aeeb8b416e167e13655242 Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Sun, 14 Mar 2021 22:54:33 +0000
Subject: [PATCH 09/23] Improve FM data tracing.

---
 Modem.cpp | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/Modem.cpp b/Modem.cpp
index 6af10d2..795302b 100644
--- a/Modem.cpp
+++ b/Modem.cpp
@@ -1078,8 +1078,12 @@ void CModem::clock(unsigned int ms)
 		m_txFMData.getData((unsigned char*)&len, sizeof(unsigned int));
 		m_txFMData.getData(m_buffer, len);
 
-		if (m_trace)
-			CUtils::dump(1U, "TX FM Data", m_buffer, len);
+		if (m_trace) {
+			if (m_buffer[2U] == MMDVM_FM_CONTROL)
+				CUtils::dump(1U, "TX FM Control", m_buffer, len);
+			else
+				CUtils::dump(1U, "TX FM Data", m_buffer, len);
+		}
 
 		int ret = m_port->write(m_buffer, len);
 		if (ret != int(len))

From 629cdcfb2ac7e3168dce987d88cca75dc7d1e443 Mon Sep 17 00:00:00 2001
From: Daniel Caujolle-Bert <f1rmb.daniel@naboo-homelinux.org>
Date: Sat, 20 Mar 2021 18:08:02 +0100
Subject: [PATCH 10/23] Unitying RemoteCommand with latest DMRGateway's
 RemoteControl PR.

---
 RemoteCommand.cpp | 21 ++++++++++++++++++++-
 RemoteControl.cpp | 18 +++++++++++++++---
 2 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/RemoteCommand.cpp b/RemoteCommand.cpp
index 143895c..20db947 100644
--- a/RemoteCommand.cpp
+++ b/RemoteCommand.cpp
@@ -22,6 +22,10 @@
 #include "Log.h"
 
 #include <cstdio>
+#include <chrono>
+#include <thread>
+
+const unsigned int BUFFER_LENGTH = 100U;
 
 int main(int argc, char** argv)
 {
@@ -67,6 +71,9 @@ int CRemoteCommand::send(const std::string& command)
 {
 	sockaddr_storage addr;
 	unsigned int addrLen;
+	char buffer[BUFFER_LENGTH];
+	int retStatus = 0;
+
 	if (CUDPSocket::lookup("127.0.0.1", m_port, addr, addrLen) != 0) {
 		LogError("Unable to resolve the address of the host");
 		return 1;
@@ -86,7 +93,19 @@ int CRemoteCommand::send(const std::string& command)
 
 	LogMessage("Command sent: \"%s\" to port: %u", command.c_str(), m_port);
 
+	std::this_thread::sleep_for(std::chrono::milliseconds(50));
+	
+	int len = socket.read((unsigned char*)&buffer[0], BUFFER_LENGTH, addr, addrLen);
+	if (len > 0) {
+		buffer[len] = '\0';
+		LogMessage("%s", buffer);
+	}
+	else
+	{
+		retStatus = 1;
+	}
+	
 	socket.close();
 
-	return 0;
+	return retStatus;
 }
diff --git a/RemoteControl.cpp b/RemoteControl.cpp
index b42718f..5274829 100644
--- a/RemoteControl.cpp
+++ b/RemoteControl.cpp
@@ -55,7 +55,8 @@ REMOTE_COMMAND CRemoteControl::getCommand()
 	m_args.clear();
 
 	char command[BUFFER_LENGTH];
-	char buffer[BUFFER_LENGTH];
+	char buffer[BUFFER_LENGTH * 2];
+	std::string replyStr = "OK";
 	sockaddr_storage address;
 	unsigned int addrlen;
 	int ret = m_socket.read((unsigned char*)buffer, BUFFER_LENGTH, address, addrlen);
@@ -89,6 +90,8 @@ REMOTE_COMMAND CRemoteControl::getCommand()
 				m_command = RCD_MODE_P25;
 			else if (m_args.at(1U) == "nxdn")
 				m_command = RCD_MODE_NXDN;
+			else
+				replyStr = "KO";
 		} else if (m_args.at(0U) == "enable" && m_args.size() >= ENABLE_ARGS) {
 			if (m_args.at(1U) == "dstar")
 				m_command = RCD_ENABLE_DSTAR;
@@ -102,6 +105,8 @@ REMOTE_COMMAND CRemoteControl::getCommand()
 				m_command = RCD_ENABLE_NXDN;
 			else if (m_args.at(1U) == "fm")
 				m_command = RCD_ENABLE_FM;
+			else
+				replyStr = "KO";
 		} else if (m_args.at(0U) == "disable" && m_args.size() >= DISABLE_ARGS) {
 			if (m_args.at(1U) == "dstar")
 				m_command = RCD_DISABLE_DSTAR;
@@ -115,6 +120,8 @@ REMOTE_COMMAND CRemoteControl::getCommand()
 				m_command = RCD_DISABLE_NXDN;
 			else if (m_args.at(1U) == "fm")
 				m_command = RCD_DISABLE_FM;
+			else
+				replyStr = "KO";
 		} else if (m_args.at(0U) == "page" && m_args.size() >= PAGE_ARGS) {
 			// Page command is in the form of "page <ric> <message>"
 			m_command = RCD_PAGE;
@@ -125,13 +132,18 @@ REMOTE_COMMAND CRemoteControl::getCommand()
                         // Reload command is in the form of "reload"
                         m_command = RCD_RELOAD;
                 }
+		else
+			replyStr = "KO";
 
+		::snprintf(buffer, BUFFER_LENGTH * 2, "%s remote command of \"%s\" received", ((m_command == RCD_NONE) ? "Invalid" : "Valid"), command);
 		if (m_command == RCD_NONE) {
 			m_args.clear();
-			LogWarning("Invalid remote command of \"%s\" received", command);
+			LogWarning(buffer);
 		} else {
-			LogMessage("Valid remote command of \"%s\" received", command);
+			LogMessage(buffer);
 		}
+		
+		m_socket.write((unsigned char*)replyStr.c_str(), replyStr.length(), address, addrlen);
 	}
 	
 	return m_command;

From 27b7d3fc4147af66bc007b8d87c2a122cf31fda5 Mon Sep 17 00:00:00 2001
From: Daniel Caujolle-Bert <f1rmb.daniel@naboo-homelinux.org>
Date: Mon, 22 Mar 2021 20:27:08 +0100
Subject: [PATCH 11/23] Add RemoteCommand 'status' command.

As DMRGateway, it reports connection status.

Command sent: "status" to port: 7642
dstar:n/a dmr:conn ysf:n/a p25:n/a nxdn:n/a fm:n/a

RemoveCommand has been slighlty modified, as using Log on a read-only filesystem simply forbids the strings to be displayed.
Another solution would be to set LogInitialisse's filePath to "/tmp/" for *nix systems.
---
 DMRDirectNetwork.cpp   |  5 +++++
 DMRDirectNetwork.h     |  2 ++
 DMRGatewayNetwork.cpp  |  5 +++++
 DMRGatewayNetwork.h    |  2 ++
 DMRNetwork.h           |  2 ++
 DStarNetwork.cpp       |  5 +++++
 DStarNetwork.h         |  2 ++
 MMDVMHost.cpp          | 13 ++++++++++++-
 MMDVMHost.h            |  2 ++
 NXDNIcomNetwork.cpp    |  5 +++++
 NXDNIcomNetwork.h      |  2 ++
 NXDNKenwoodNetwork.cpp |  5 +++++
 NXDNKenwoodNetwork.h   |  2 ++
 NXDNNetwork.h          |  2 ++
 P25Network.cpp         |  5 +++++
 P25Network.h           |  2 ++
 RemoteCommand.cpp      |  8 ++++----
 RemoteControl.cpp      | 15 +++++++++++++--
 RemoteControl.h        |  8 ++++++--
 YSFNetwork.cpp         |  5 +++++
 YSFNetwork.h           |  2 ++
 21 files changed, 90 insertions(+), 9 deletions(-)

diff --git a/DMRDirectNetwork.cpp b/DMRDirectNetwork.cpp
index 4ed871c..a378f7a 100644
--- a/DMRDirectNetwork.cpp
+++ b/DMRDirectNetwork.cpp
@@ -316,6 +316,11 @@ bool CDMRDirectNetwork::writeTalkerAlias(unsigned int id, unsigned char type, co
 	return write(buffer, 15U);
 }
 
+bool CDMRDirectNetwork::isConnected() const
+{
+	return (m_status == RUNNING);
+}
+
 void CDMRDirectNetwork::close()
 {
 	LogMessage("Closing DMR Network");
diff --git a/DMRDirectNetwork.h b/DMRDirectNetwork.h
index 30ba951..f6e0834 100644
--- a/DMRDirectNetwork.h
+++ b/DMRDirectNetwork.h
@@ -55,6 +55,8 @@ public:
 
 	virtual void clock(unsigned int ms);
 
+	virtual bool isConnected() const;
+
 	virtual void close();
 
 private:
diff --git a/DMRGatewayNetwork.cpp b/DMRGatewayNetwork.cpp
index 5150d77..dd86e76 100644
--- a/DMRGatewayNetwork.cpp
+++ b/DMRGatewayNetwork.cpp
@@ -287,6 +287,11 @@ bool CDMRGatewayNetwork::writeTalkerAlias(unsigned int id, unsigned char type, c
 	return write(buffer, 15U);
 }
 
+bool CDMRGatewayNetwork::isConnected() const
+{
+	return (m_enabled && (m_addrLen != 0));
+}
+
 void CDMRGatewayNetwork::close()
 {
 	LogMessage("DMR, Closing DMR Network");
diff --git a/DMRGatewayNetwork.h b/DMRGatewayNetwork.h
index 55afc72..bc00385 100644
--- a/DMRGatewayNetwork.h
+++ b/DMRGatewayNetwork.h
@@ -56,6 +56,8 @@ public:
 
 	virtual void clock(unsigned int ms);
 
+	virtual bool isConnected() const;
+
 	virtual void close();
 
 private: 
diff --git a/DMRNetwork.h b/DMRNetwork.h
index 69d3926..4a3c4d7 100644
--- a/DMRNetwork.h
+++ b/DMRNetwork.h
@@ -48,6 +48,8 @@ public:
 
 	virtual void clock(unsigned int ms) = 0;
 
+	virtual bool isConnected() const = 0;
+
 	virtual void close() = 0;
 
 private: 
diff --git a/DStarNetwork.cpp b/DStarNetwork.cpp
index 21bbc9d..4a978e2 100644
--- a/DStarNetwork.cpp
+++ b/DStarNetwork.cpp
@@ -314,6 +314,11 @@ void CDStarNetwork::reset()
 	m_inId = 0U;
 }
 
+bool CDStarNetwork::isConnected() const
+{
+	return (m_enabled && (m_addrLen != 0));
+}
+
 void CDStarNetwork::close()
 {
 	m_socket.close();
diff --git a/DStarNetwork.h b/DStarNetwork.h
index 1e0d5f0..cb41b78 100644
--- a/DStarNetwork.h
+++ b/DStarNetwork.h
@@ -46,6 +46,8 @@ public:
 
 	void reset();
 
+	bool isConnected() const;
+
 	void close();
 
 	void clock(unsigned int ms);
diff --git a/MMDVMHost.cpp b/MMDVMHost.cpp
index 2d76284..8409aac 100644
--- a/MMDVMHost.cpp
+++ b/MMDVMHost.cpp
@@ -635,7 +635,7 @@ int CMMDVMHost::run()
 		LogInfo("    Address: %s", address.c_str());
 		LogInfo("    Port: %u", port);
 
-		m_remoteControl = new CRemoteControl(address, port);
+		m_remoteControl = new CRemoteControl(this, address, port);
 
 		ret = m_remoteControl->open();
 		if (!ret) {
@@ -2140,3 +2140,14 @@ void CMMDVMHost::processEnableCommand(bool& mode, bool enabled)
 	if (!m_modem->writeConfig())
 		LogError("Cannot write Config to MMDVM");
 }
+
+void CMMDVMHost::buildNetworkStatusString(std::string &str)
+{
+	str = "";
+	str += std::string("dstar:") + (((m_dstarNetwork == NULL) || (m_dstarEnabled == false)) ? "n/a" : (m_dstarNetwork->isConnected() ? "conn" : "disc"));
+	str += std::string(" dmr:") + (((m_dmrNetwork == NULL) || (m_dmrEnabled == false)) ? "n/a" : (m_dmrNetwork->isConnected() ? "conn" : "disc"));
+	str += std::string(" ysf:") + (((m_ysfNetwork == NULL) || (m_ysfEnabled == false)) ? "n/a" : (m_ysfNetwork->isConnected() ? "conn" : "disc"));
+	str += std::string(" p25:") + (((m_p25Network == NULL) || (m_p25Enabled == false)) ? "n/a" : (m_p25Network->isConnected() ? "conn" : "disc"));
+	str += std::string(" nxdn:") + (((m_nxdnNetwork == NULL) || (m_nxdnEnabled == false)) ? "n/a" : (m_nxdnNetwork->isConnected() ? "conn" : "disc"));
+	str += std::string(" fm:") + (m_fmEnabled ? "conn" : "n/a");
+}
diff --git a/MMDVMHost.h b/MMDVMHost.h
index 735952a..dd8ccf4 100644
--- a/MMDVMHost.h
+++ b/MMDVMHost.h
@@ -51,6 +51,8 @@ public:
 
   int run();
 
+  void buildNetworkStatusString(std::string &str);
+
 private:
   CConf           m_conf;
   CModem*         m_modem;
diff --git a/NXDNIcomNetwork.cpp b/NXDNIcomNetwork.cpp
index b13ca2a..5f20b37 100644
--- a/NXDNIcomNetwork.cpp
+++ b/NXDNIcomNetwork.cpp
@@ -153,6 +153,11 @@ void CNXDNIcomNetwork::reset()
 {
 }
 
+bool CNXDNIcomNetwork::isConnected() const
+{
+	return (m_enabled && (m_addrLen != 0));
+}
+
 void CNXDNIcomNetwork::close()
 {
 	m_socket.close();
diff --git a/NXDNIcomNetwork.h b/NXDNIcomNetwork.h
index 3113a9f..9f74710 100644
--- a/NXDNIcomNetwork.h
+++ b/NXDNIcomNetwork.h
@@ -43,6 +43,8 @@ public:
 
 	virtual void reset();
 
+	virtual bool isConnected() const;
+
 	virtual void close();
 
 	virtual void clock(unsigned int ms);
diff --git a/NXDNKenwoodNetwork.cpp b/NXDNKenwoodNetwork.cpp
index 67de39b..3866133 100644
--- a/NXDNKenwoodNetwork.cpp
+++ b/NXDNKenwoodNetwork.cpp
@@ -835,6 +835,11 @@ void CNXDNKenwoodNetwork::reset()
 	m_seen4 = false;
 }
 
+bool CNXDNKenwoodNetwork::isConnected() const
+{
+	return (m_enabled && (m_rtcpAddrLen != 0U) && (m_rtpAddrLen != 0U));
+}
+
 void CNXDNKenwoodNetwork::close()
 {
 	m_rtcpSocket.close();
diff --git a/NXDNKenwoodNetwork.h b/NXDNKenwoodNetwork.h
index af28618..dc7bf1d 100644
--- a/NXDNKenwoodNetwork.h
+++ b/NXDNKenwoodNetwork.h
@@ -42,6 +42,8 @@ public:
 
 	virtual void reset();
 
+	virtual bool isConnected() const;
+
 	virtual void close();
 
 	virtual void clock(unsigned int ms);
diff --git a/NXDNNetwork.h b/NXDNNetwork.h
index 564196b..107e02f 100644
--- a/NXDNNetwork.h
+++ b/NXDNNetwork.h
@@ -46,6 +46,8 @@ public:
 
 	virtual void reset() = 0;
 
+	virtual bool isConnected() const = 0;
+
 	virtual void close() = 0;
 
 	virtual void clock(unsigned int ms) = 0;
diff --git a/P25Network.cpp b/P25Network.cpp
index 3bb39b9..2734373 100644
--- a/P25Network.cpp
+++ b/P25Network.cpp
@@ -424,6 +424,11 @@ unsigned int CP25Network::read(unsigned char* data, unsigned int length)
 	return c;
 }
 
+bool CP25Network::isConnected() const
+{
+	return (m_enabled && (m_addrLen != 0));
+}
+
 void CP25Network::close()
 {
 	m_socket.close();
diff --git a/P25Network.h b/P25Network.h
index 4c52761..6b8407c 100644
--- a/P25Network.h
+++ b/P25Network.h
@@ -43,6 +43,8 @@ public:
 
 	unsigned int read(unsigned char* data, unsigned int length);
 
+	bool isConnected() const;
+
 	void close();
 
 	void clock(unsigned int ms);
diff --git a/RemoteCommand.cpp b/RemoteCommand.cpp
index 20db947..c893d79 100644
--- a/RemoteCommand.cpp
+++ b/RemoteCommand.cpp
@@ -75,7 +75,7 @@ int CRemoteCommand::send(const std::string& command)
 	int retStatus = 0;
 
 	if (CUDPSocket::lookup("127.0.0.1", m_port, addr, addrLen) != 0) {
-		LogError("Unable to resolve the address of the host");
+		::fprintf(stderr, "Unable to resolve the address of the host\n");
 		return 1;
 	}
 
@@ -91,14 +91,14 @@ int CRemoteCommand::send(const std::string& command)
 		return 1;
 	}
 
-	LogMessage("Command sent: \"%s\" to port: %u", command.c_str(), m_port);
+	::fprintf(stdout, "Command sent: \"%s\" to port: %u\n", command.c_str(), m_port);
 
 	std::this_thread::sleep_for(std::chrono::milliseconds(50));
 	
-	int len = socket.read((unsigned char*)&buffer[0], BUFFER_LENGTH, addr, addrLen);
+	int len = socket.read((unsigned char*)buffer, BUFFER_LENGTH, addr, addrLen);
 	if (len > 0) {
 		buffer[len] = '\0';
-		LogMessage("%s", buffer);
+		::fprintf(stdout, "%s\n", buffer);
 	}
 	else
 	{
diff --git a/RemoteControl.cpp b/RemoteControl.cpp
index 5274829..a195d35 100644
--- a/RemoteControl.cpp
+++ b/RemoteControl.cpp
@@ -17,6 +17,7 @@
  */
 
 #include "RemoteControl.h"
+#include "MMDVMHost.h"
 #include "Log.h"
 
 #include <cstdio>
@@ -32,7 +33,8 @@ const unsigned int CW_ARGS = 2U;
 
 const unsigned int BUFFER_LENGTH = 100U;
 
-CRemoteControl::CRemoteControl(const std::string address, unsigned int port) :
+CRemoteControl::CRemoteControl(CMMDVMHost *host, const std::string address, unsigned int port) :
+m_host(host),
 m_socket(address, port),
 m_command(RCD_NONE),
 m_args()
@@ -131,7 +133,16 @@ REMOTE_COMMAND CRemoteControl::getCommand()
 		} else if (m_args.at(0U) == "reload") {
                         // Reload command is in the form of "reload"
                         m_command = RCD_RELOAD;
-                }
+		} else if (m_args.at(0U) == "status") {
+			if (m_host != NULL) {
+				m_host->buildNetworkStatusString(replyStr);
+			}
+			else {
+				replyStr = "KO";
+			}
+
+			m_command = RCD_CONNECTION_STATUS;
+		}
 		else
 			replyStr = "KO";
 
diff --git a/RemoteControl.h b/RemoteControl.h
index 3f07f03..addbb3e 100644
--- a/RemoteControl.h
+++ b/RemoteControl.h
@@ -24,6 +24,8 @@
 #include <vector>
 #include <string>
 
+class CMMDVMHost;
+
 enum REMOTE_COMMAND {
 	RCD_NONE,
 	RCD_MODE_IDLE,
@@ -48,12 +50,13 @@ enum REMOTE_COMMAND {
 	RCD_DISABLE_FM,
 	RCD_PAGE,
 	RCD_CW,
-	RCD_RELOAD
+	RCD_RELOAD,
+	RCD_CONNECTION_STATUS
 };
 
 class CRemoteControl {
 public:
-	CRemoteControl(const std::string address, unsigned int port);
+	CRemoteControl(class CMMDVMHost *host, const std::string address, unsigned int port);
 	~CRemoteControl();
 
 	bool open();
@@ -69,6 +72,7 @@ public:
 	void close();
 
 private:
+	CMMDVMHost*              m_host;
 	CUDPSocket               m_socket;
 	REMOTE_COMMAND           m_command;
 	std::vector<std::string> m_args;
diff --git a/YSFNetwork.cpp b/YSFNetwork.cpp
index 089a932..451d3af 100644
--- a/YSFNetwork.cpp
+++ b/YSFNetwork.cpp
@@ -183,6 +183,11 @@ void CYSFNetwork::reset()
 	::memset(m_tag, ' ', YSF_CALLSIGN_LENGTH);
 }
 
+bool CYSFNetwork::isConnected() const
+{
+	return (m_enabled && (m_addrLen != 0));
+}
+
 void CYSFNetwork::close()
 {
 	m_socket.close();
diff --git a/YSFNetwork.h b/YSFNetwork.h
index aef43d3..3fd7c56 100644
--- a/YSFNetwork.h
+++ b/YSFNetwork.h
@@ -42,6 +42,8 @@ public:
 
 	void reset();
 
+	bool isConnected() const;
+
 	void close();
 
 	void clock(unsigned int ms);

From b5420fef155c35bca1987ddb7175d55604b25671 Mon Sep 17 00:00:00 2001
From: Daniel Caujolle-Bert <f1rmb.daniel@naboo-homelinux.org>
Date: Tue, 23 Mar 2021 22:32:36 +0100
Subject: [PATCH 12/23] Fix *Network::isConnected(). As m_enabled is changed
 accordingly to the modem current mode, it's not valid to use it for network
 connexion status.

---
 DMRGatewayNetwork.cpp  | 2 +-
 DStarNetwork.cpp       | 2 +-
 NXDNIcomNetwork.cpp    | 2 +-
 NXDNKenwoodNetwork.cpp | 2 +-
 P25Network.cpp         | 2 +-
 YSFNetwork.cpp         | 2 +-
 6 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/DMRGatewayNetwork.cpp b/DMRGatewayNetwork.cpp
index dd86e76..775a79d 100644
--- a/DMRGatewayNetwork.cpp
+++ b/DMRGatewayNetwork.cpp
@@ -289,7 +289,7 @@ bool CDMRGatewayNetwork::writeTalkerAlias(unsigned int id, unsigned char type, c
 
 bool CDMRGatewayNetwork::isConnected() const
 {
-	return (m_enabled && (m_addrLen != 0));
+	return (m_addrLen != 0);
 }
 
 void CDMRGatewayNetwork::close()
diff --git a/DStarNetwork.cpp b/DStarNetwork.cpp
index 4a978e2..c702cfa 100644
--- a/DStarNetwork.cpp
+++ b/DStarNetwork.cpp
@@ -316,7 +316,7 @@ void CDStarNetwork::reset()
 
 bool CDStarNetwork::isConnected() const
 {
-	return (m_enabled && (m_addrLen != 0));
+	return (m_addrLen != 0);
 }
 
 void CDStarNetwork::close()
diff --git a/NXDNIcomNetwork.cpp b/NXDNIcomNetwork.cpp
index 5f20b37..730f445 100644
--- a/NXDNIcomNetwork.cpp
+++ b/NXDNIcomNetwork.cpp
@@ -155,7 +155,7 @@ void CNXDNIcomNetwork::reset()
 
 bool CNXDNIcomNetwork::isConnected() const
 {
-	return (m_enabled && (m_addrLen != 0));
+	return (m_addrLen != 0);
 }
 
 void CNXDNIcomNetwork::close()
diff --git a/NXDNKenwoodNetwork.cpp b/NXDNKenwoodNetwork.cpp
index 3866133..bed3316 100644
--- a/NXDNKenwoodNetwork.cpp
+++ b/NXDNKenwoodNetwork.cpp
@@ -837,7 +837,7 @@ void CNXDNKenwoodNetwork::reset()
 
 bool CNXDNKenwoodNetwork::isConnected() const
 {
-	return (m_enabled && (m_rtcpAddrLen != 0U) && (m_rtpAddrLen != 0U));
+	return ((m_rtcpAddrLen != 0U) && (m_rtpAddrLen != 0U));
 }
 
 void CNXDNKenwoodNetwork::close()
diff --git a/P25Network.cpp b/P25Network.cpp
index 2734373..77a9a7d 100644
--- a/P25Network.cpp
+++ b/P25Network.cpp
@@ -426,7 +426,7 @@ unsigned int CP25Network::read(unsigned char* data, unsigned int length)
 
 bool CP25Network::isConnected() const
 {
-	return (m_enabled && (m_addrLen != 0));
+	return (m_addrLen != 0);
 }
 
 void CP25Network::close()
diff --git a/YSFNetwork.cpp b/YSFNetwork.cpp
index 451d3af..3fc5eb6 100644
--- a/YSFNetwork.cpp
+++ b/YSFNetwork.cpp
@@ -185,7 +185,7 @@ void CYSFNetwork::reset()
 
 bool CYSFNetwork::isConnected() const
 {
-	return (m_enabled && (m_addrLen != 0));
+	return (m_addrLen != 0);
 }
 
 void CYSFNetwork::close()

From dbf771d80c51c3469a9275de9afbc3346d119ebf Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Thu, 25 Mar 2021 21:07:44 +0000
Subject: [PATCH 13/23] Fixed M17 to be compatible with the latest protocol
 speciication.

---
 Conf.cpp                  |  10 +-
 Conf.h                    |   4 +-
 M17CRC.cpp                |   2 +-
 M17Control.cpp            | 396 ++++++++++++++++++++------------------
 M17Control.h              |  19 +-
 M17Convolution.cpp        |   2 +-
 M17Convolution.h          |   2 +-
 M17Defines.h              |  25 ++-
 M17LICH.cpp               | 143 --------------
 M17LSF.cpp                | 193 +++++++++++++++++++
 M17LICH.h => M17LSF.h     |  26 ++-
 M17Network.cpp            |   2 +-
 M17Network.h              |   2 +-
 M17Utils.cpp              |  15 +-
 MMDVM.ini                 |   2 +-
 MMDVMHost.cpp             |   6 +-
 MMDVMHost.vcxproj         |   4 +-
 MMDVMHost.vcxproj.filters |   4 +-
 Makefile                  |   2 +-
 Makefile.Pi               |   2 +-
 Makefile.Pi.Adafruit      |   2 +-
 Makefile.Pi.HD44780       |   2 +-
 Makefile.Pi.OLED          |   2 +-
 Makefile.Pi.PCF8574       |   2 +-
 Version.h                 |   2 +-
 25 files changed, 481 insertions(+), 390 deletions(-)
 delete mode 100644 M17LICH.cpp
 create mode 100644 M17LSF.cpp
 rename M17LICH.h => M17LSF.h (73%)

diff --git a/Conf.cpp b/Conf.cpp
index 83d22f4..dcc9bc4 100644
--- a/Conf.cpp
+++ b/Conf.cpp
@@ -182,7 +182,7 @@ m_nxdnRemoteGateway(false),
 m_nxdnTXHang(5U),
 m_nxdnModeHang(10U),
 m_m17Enabled(false),
-m_m17ColorCode(1U),
+m_m17CAN(0U),
 m_m17SelfOnly(false),
 m_m17AllowEncryption(false),
 m_m17TXHang(5U),
@@ -779,8 +779,8 @@ bool CConf::read()
 		} else if (section == SECTION_M17) {
 			if (::strcmp(key, "Enable") == 0)
 				m_m17Enabled = ::atoi(value) == 1;
-			else if (::strcmp(key, "ColorCode") == 0)
-				m_m17ColorCode = (unsigned int)::atoi(value);
+			else if (::strcmp(key, "CAN") == 0)
+				m_m17CAN = (unsigned int)::atoi(value);
 			else if (::strcmp(key, "SelfOnly") == 0)
 				m_m17SelfOnly = ::atoi(value) == 1;
 			else if (::strcmp(key, "AllowEncryption") == 0)
@@ -1707,9 +1707,9 @@ bool CConf::getM17Enabled() const
 	return m_m17Enabled;
 }
 
-unsigned int CConf::getM17ColorCode() const
+unsigned int CConf::getM17CAN() const
 {
-	return m_m17ColorCode;
+	return m_m17CAN;
 }
 
 bool CConf::getM17SelfOnly() const
diff --git a/Conf.h b/Conf.h
index aad1155..dc31ef5 100644
--- a/Conf.h
+++ b/Conf.h
@@ -173,7 +173,7 @@ public:
 
   // The M17 section
   bool         getM17Enabled() const;
-  unsigned int getM17ColorCode() const;
+  unsigned int getM17CAN() const;
   bool         getM17SelfOnly() const;
   bool         getM17AllowEncryption() const;
   unsigned int getM17TXHang() const;
@@ -496,7 +496,7 @@ private:
   unsigned int m_nxdnModeHang;
 
   bool         m_m17Enabled;
-  unsigned int m_m17ColorCode;
+  unsigned int m_m17CAN;
   bool         m_m17SelfOnly;
   bool         m_m17AllowEncryption;
   unsigned int m_m17TXHang;
diff --git a/M17CRC.cpp b/M17CRC.cpp
index 7ba4da6..cd41697 100644
--- a/M17CRC.cpp
+++ b/M17CRC.cpp
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2018,2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
diff --git a/M17Control.cpp b/M17Control.cpp
index a36d0eb..5ab306e 100644
--- a/M17Control.cpp
+++ b/M17Control.cpp
@@ -1,5 +1,5 @@
 /*
- *	Copyright (C) 2015-2020 Jonathan Naylor, G4KLX
+ *	Copyright (C) 2020,2021 Jonathan Naylor, G4KLX
  *
  *	This program is free software; you can redistribute it and/or modify
  *	it under the terms of the GNU General Public License as published by
@@ -57,9 +57,9 @@ const unsigned char BIT_MASK_TABLE[] = { 0x80U, 0x40U, 0x20U, 0x10U, 0x08U, 0x04
 #define WRITE_BIT(p,i,b) p[(i)>>3] = (b) ? (p[(i)>>3] | BIT_MASK_TABLE[(i)&7]) : (p[(i)>>3] & ~BIT_MASK_TABLE[(i)&7])
 #define READ_BIT(p,i)    (p[(i)>>3] & BIT_MASK_TABLE[(i)&7])
 
-CM17Control::CM17Control(const std::string& callsign, unsigned int colorCode, bool selfOnly, bool allowEncryption, CM17Network* network, CDisplay* display, unsigned int timeout, bool duplex, CRSSIInterpolator* rssiMapper) :
+CM17Control::CM17Control(const std::string& callsign, unsigned int can, bool selfOnly, bool allowEncryption, CM17Network* network, CDisplay* display, unsigned int timeout, bool duplex, CRSSIInterpolator* rssiMapper) :
 m_callsign(callsign),
-m_colorCode(colorCode),
+m_can(can),
 m_selfOnly(selfOnly),
 m_allowEncryption(allowEncryption),
 m_network(network),
@@ -78,10 +78,10 @@ m_netFrames(0U),
 m_rfFN(0U),
 m_rfErrs(0U),
 m_rfBits(1U),
-m_rfLICH(),
-m_rfLICHn(0U),
-m_netLICH(),
-m_netLICHn(0U),
+m_rfLSF(),
+m_rfLSFn(0U),
+m_netLSF(),
+m_netLSFn(0U),
 m_rssiMapper(rssiMapper),
 m_rssi(0U),
 m_maxRSSI(0U),
@@ -109,8 +109,8 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 	unsigned char type = data[0U];
 
 	if (type == TAG_LOST && m_rfState == RS_RF_AUDIO) {
-		std::string source = m_rfLICH.getSource();
-		std::string dest = m_rfLICH.getDest();
+		std::string source = m_rfLSF.getSource();
+		std::string dest   = m_rfLSF.getDest();
 
 		if (m_rssi != 0U)
 			LogMessage("M17, transmission lost from %s to %s, %.1f seconds, BER: %.1f%%, RSSI: -%u/-%u/-%u dBm", source.c_str(), dest.c_str(), float(m_rfFrames) / 25.0F, float(m_rfErrs * 100U) / float(m_rfBits), m_minRSSI, m_maxRSSI, m_aveRSSI / m_rssiCount);
@@ -125,6 +125,11 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		return false;
 	}
 
+	if (type == TAG_LOST && m_rfState == RS_RF_REJECTED) {
+		writeEndRF();
+		return false;
+	}
+
 	if (type == TAG_LOST) {
 		m_rfState = RS_RF_LISTENING;
 		return false;
@@ -158,14 +163,22 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 	interleaver(temp, data + 2U);
 
 	if (m_rfState == RS_RF_LISTENING && data[0U] == TAG_HEADER) {
-		m_rfLICH.reset();
+		m_rfLSF.reset();
 
 		CM17Convolution conv;
-		unsigned char frame[M17_LICH_LENGTH_BYTES];
+		unsigned char frame[M17_LSF_LENGTH_BYTES];
 		conv.decodeLinkSetup(data + 2U + M17_SYNC_LENGTH_BYTES, frame);
 
-		bool valid = CM17CRC::checkCRC(frame, M17_LICH_LENGTH_BYTES);
+		bool valid = CM17CRC::checkCRC(frame, M17_LSF_LENGTH_BYTES);
 		if (valid) {
+			m_rfLSF.setLinkSetup(frame);
+
+			bool ret = processRFHeader(false);
+			if (!ret) {
+				m_rfLSF.reset();
+				return false;
+			}
+
 			m_rfFrames = 0U;
 			m_rfErrs = 0U;
 			m_rfBits = 1U;
@@ -174,22 +187,23 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 			m_maxRSSI = m_rssi;
 			m_aveRSSI = m_rssi;
 			m_rssiCount = 1U;
-			m_rfLICHn   = 0U;
+			m_rfLSFn    = 0U;
 			m_rfFN      = 0U;
 
 #if defined(DUMP_M17)
 			openFile();
 #endif
-			m_rfLICH.setLinkSetup(frame);
-
-			m_rfState = RS_RF_LATE_ENTRY;
-
 			return true;
 		} else {
 			m_rfState = RS_RF_LATE_ENTRY;
 		}
 	}
 
+	if (m_rfState == RS_RF_LISTENING && data[0U] == TAG_DATA) {
+		m_rfState = RS_RF_LATE_ENTRY;
+		m_rfLSF.reset();
+	}
+
 	if (m_rfState == RS_RF_LATE_ENTRY && data[0U] == TAG_DATA) {
 		unsigned int frag1, frag2, frag3, frag4;
 		CM17Utils::splitFragmentLICHFEC(data + 2U + M17_SYNC_LENGTH_BYTES, frag1, frag2, frag3, frag4);
@@ -199,23 +213,24 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		unsigned int lich3 = CGolay24128::decode24128(frag3);
 		unsigned int lich4 = CGolay24128::decode24128(frag4);
 
-		unsigned int colorCode = (lich4 >> 7) & 0x1FU;
-		if (colorCode != m_colorCode)
+		unsigned int can = lich4 & 0x1FU;
+		if (can != m_can)
 			return false;
 
-		bool lateEntry = false;
-		if (!m_rfLICH.isValid()) {
-			unsigned char lich[M17_LICH_FRAGMENT_LENGTH_BYTES];
-			CM17Utils::combineFragmentLICH(lich1, lich2, lich3, lich4, lich);
+		unsigned char lich[M17_LICH_FRAGMENT_LENGTH_BYTES];
+		CM17Utils::combineFragmentLICH(lich1, lich2, lich3, lich4, lich);
 
-			unsigned int n = (lich4 >> 4) & 0x07U;
-			m_rfLICH.setFragment(lich, n);
+		m_rfLSFn = (lich4 >> 5) & 0x07U;
+		m_rfLSF.setFragment(lich, m_rfLSFn);
 
-			lateEntry = true;
-		}
-
-		bool valid = m_rfLICH.isValid();
+		bool valid = m_rfLSF.isValid();
 		if (valid) {
+			bool ret = processRFHeader(true);
+			if (!ret) {
+				m_rfLSF.reset();
+				return false;
+			}
+
 			m_rfFrames = 0U;
 			m_rfErrs = 0U;
 			m_rfBits = 1U;
@@ -224,68 +239,13 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 			m_maxRSSI = m_rssi;
 			m_aveRSSI = m_rssi;
 			m_rssiCount = 1U;
-			m_rfLICHn   = 0U;
 
 #if defined(DUMP_M17)
 			openFile();
 #endif
-			std::string source = m_rfLICH.getSource();
-			std::string dest   = m_rfLICH.getDest();
-
-			if (m_selfOnly) {
-				bool ret = checkCallsign(source);
-				if (!ret) {
-					LogMessage("M17, invalid access attempt from %s to %s", source.c_str(), dest.c_str());
-					m_rfState = RS_RF_REJECTED;
-					return false;
-				}
-			}
-
-			unsigned char dataType = m_rfLICH.getDataType();
-			switch (dataType) {
-			case 1U:
-				LogMessage("M17, received RF %s data transmission from %s to %s", lateEntry ? "late entry" : "", source.c_str(), dest.c_str());
-				m_rfState = RS_RF_DATA;
-				break;
-			case 2U:
-				LogMessage("M17, received RF %s voice transmission from %s to %s", lateEntry ? "late entry" : "", source.c_str(), dest.c_str());
-				m_rfState = RS_RF_AUDIO;
-				break;
-			case 3U:
-				LogMessage("M17, received RF %s voice + data transmission from %s to %s", lateEntry ? "late entry" : "", source.c_str(), dest.c_str());
-				m_rfState = RS_RF_AUDIO;
-				break;
-			default:
-				LogMessage("M17, received RF %s unknown transmission from %s to %s", lateEntry ? "late entry" : "", source.c_str(), dest.c_str());
-				m_rfState = RS_RF_DATA;
-				break;
-			}
-
-			m_display->writeM17(source.c_str(), dest.c_str(), "R");
-
-			if (m_duplex) {
-				// Create a Link Setup frame
-				data[0U] = TAG_HEADER;
-				data[1U] = 0x00U;
-
-				// Generate the sync
-				CSync::addM17LinkSetupSync(data + 2U);
-				
-				unsigned char setup[M17_LICH_LENGTH_BYTES];
-				m_rfLICH.getLinkSetup(setup);
-
-				// Add the convolution FEC
-				CM17Convolution conv;
-				conv.encodeLinkSetup(setup, data + 2U + M17_SYNC_LENGTH_BYTES);
-
-				unsigned char temp[M17_FRAME_LENGTH_BYTES];
-				interleaver(data + 2U, temp);
-				decorrelator(temp, data + 2U);
-
-				writeQueueRF(data);
-			}
-
-			// Fall through to the next section
+			// Fall through
+		} else {
+			return false;
 		}
 	}
 
@@ -309,13 +269,13 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 			frame[1U] = m_rfFN >> 0;
 
 			// Add silent audio
-			unsigned char dataType = m_rfLICH.getDataType();
+			unsigned char dataType = m_rfLSF.getDataType();
 			switch (dataType) {
-			case 2U:
+			case M17_DATA_TYPE_VOICE:
 				::memcpy(frame + M17_FN_LENGTH_BYTES + 0U, M17_3200_SILENCE, 8U);
 				::memcpy(frame + M17_FN_LENGTH_BYTES + 8U, M17_3200_SILENCE, 8U);
 				break;
-			case 3U:
+			case M17_DATA_TYPE_VOICE_DATA:
 				::memcpy(frame + M17_FN_LENGTH_BYTES + 0U, M17_1600_SILENCE, 8U);
 				break;
 			default:
@@ -335,14 +295,14 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		CSync::addM17StreamSync(rfData + 2U);
 
 		unsigned char lich[M17_LICH_FRAGMENT_LENGTH_BYTES];
-		m_netLICH.getFragment(lich, m_rfLICHn);
+		m_rfLSF.getFragment(lich, m_rfLSFn);
 
 		unsigned int frag1, frag2, frag3, frag4;
 		CM17Utils::splitFragmentLICH(lich, frag1, frag2, frag3, frag4);
 
-		// Add the Color Code and fragment number
-		frag4 |= (m_rfLICHn & 0x07U)   << 4;
-		frag4 |= (m_colorCode & 0x1FU) << 7;
+		// Add the CAN and fragment number
+		frag4 |= (m_rfLSFn & 0x07U) << 5;
+		frag4 |= m_can & 0x1FU;
 
 		// Add Golay to the LICH fragment here
 		unsigned int lich1 = CGolay24128::encode24128(frag1);
@@ -361,7 +321,7 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 			for (unsigned int i = 2U; i < (M17_FRAME_LENGTH_BYTES + 2U); i++)
 				errors += countBits(rfData[i] ^ data[i]);
 
-			LogDebug("M17, FN: %u, errs: %u/384 (%.1f%%)", m_rfFN, errors, float(errors) / 3.84F);
+			LogDebug("M17, FN: %u, errs: %u/384 (%.1f%%)", m_rfFN & 0x7FU, errors, float(errors) / 3.84F);
 
 			m_rfBits += M17_FRAME_LENGTH_BITS;
 			m_rfErrs += errors;
@@ -372,32 +332,34 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 
 		unsigned char temp[M17_FRAME_LENGTH_BYTES];
 		interleaver(rfData + 2U, temp);
-		decorrelator(rfData, data + 2U);
+		decorrelator(temp, rfData + 2U);
 
 		if (m_duplex)
 			writeQueueRF(rfData);
 
-		unsigned char netData[M17_LICH_LENGTH_BYTES + M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES];
+		if (m_network != NULL && m_rfTimeoutTimer.isRunning() && !m_rfTimeoutTimer.hasExpired()) {
+			unsigned char netData[M17_LSF_LENGTH_BYTES + M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES];
 
-		m_rfLICH.getNetwork(netData + 0U);
+			m_rfLSF.getNetwork(netData + 0U);
 
-		// Copy the FN and payload from the frame
-		::memcpy(netData + M17_LICH_LENGTH_BYTES - M17_CRC_LENGTH_BYTES, frame, M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES);
+			// Copy the FN and payload from the frame
+			::memcpy(netData + M17_LSF_LENGTH_BYTES - M17_CRC_LENGTH_BYTES, frame, M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES);
 
-		// The CRC is added in the networking code
+			// The CRC is added in the networking code
 
-		writeNetwork(netData);
+			m_network->write(netData);
+		}
 
 		m_rfFrames++;
 
-		m_rfLICHn++;
-		if (m_rfLICHn >= 6U)
-			m_rfLICHn = 0U;
+		m_rfLSFn++;
+		if (m_rfLSFn >= 6U)
+			m_rfLSFn = 0U;
 
 		// EOT?
 		if ((m_rfFN & 0x8000U) == 0x8000U) {
-			std::string source = m_rfLICH.getSource();
-			std::string dest   = m_rfLICH.getDest();
+			std::string source = m_rfLSF.getSource();
+			std::string dest   = m_rfLSF.getDest();
 
 			if (m_rssi != 0U)
 				LogMessage("M17, received RF end of transmission from %s to %s, %.1f seconds, BER: %.1f%%, RSSI: -%u/-%u/-%u dBm", source.c_str(), dest.c_str(), float(m_rfFrames) / 25.0F, float(m_rfErrs * 100U) / float(m_rfBits), m_minRSSI, m_maxRSSI, m_aveRSSI / m_rssiCount);
@@ -409,22 +371,6 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		return true;
 	}
 
-	if (m_rfState == RS_RF_REJECTED && data[0U] == TAG_DATA) {
-		CM17Convolution conv;
-		unsigned char frame[M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES];
-		conv.decodeData(data + 2U + M17_SYNC_LENGTH_BYTES + M17_LICH_FRAGMENT_FEC_LENGTH_BYTES, frame);
-
-		bool valid = CM17CRC::checkCRC(frame, M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES);
-		if (valid) {
-			// Handle the EOT for rejected frames
-			unsigned int fn = (frame[0U] << 8) + (frame[1U] << 0);
-			if ((fn & 0x8000U) == 0x8000U)
-				writeEndRF();
-		}
-
-		return false;
-	}
-
 	return false;
 }
 
@@ -449,7 +395,7 @@ void CM17Control::writeEndRF()
 
 	m_rfTimeoutTimer.stop();
 
-	m_rfLICH.reset();
+	m_rfLSF.reset();
 
 	if (m_netState == RS_NET_IDLE) {
 		m_display->clearM17();
@@ -471,7 +417,7 @@ void CM17Control::writeEndNet()
 	m_networkWatchdog.stop();
 	m_packetTimer.stop();
 
-	m_netLICH.reset();
+	m_netLSF.reset();
 
 	m_display->clearM17();
 
@@ -494,29 +440,30 @@ void CM17Control::writeNetwork()
 
 	m_networkWatchdog.start();
 
-	m_netLICH.setNetwork(netData);
+	m_netLSF.setNetwork(netData);
+	m_netLSF.setCAN(m_can);
 
 	if (!m_allowEncryption) {
-		bool ret = m_rfLICH.isNONCENull();
-		if (!ret)
+		unsigned char type = m_netLSF.getEncryptionType();
+		if (type != M17_ENCRYPTION_TYPE_NONE)
 			return;
 	}
 
 	if (m_netState == RS_NET_IDLE) {
-		std::string source = m_netLICH.getSource();
-		std::string dest   = m_netLICH.getDest();
+		std::string source = m_netLSF.getSource();
+		std::string dest   = m_netLSF.getDest();
 
-		unsigned char dataType = m_netLICH.getDataType();
+		unsigned char dataType = m_netLSF.getDataType();
 		switch (dataType) {
-		case 1U:
+		case M17_DATA_TYPE_DATA:
 			LogMessage("M17, received network data transmission from %s to %s", source.c_str(), dest.c_str());
 			m_netState = RS_NET_DATA;
 			break;
-		case 2U:
+		case M17_DATA_TYPE_VOICE:
 			LogMessage("M17, received network voice transmission from %s to %s", source.c_str(), dest.c_str());
 			m_netState = RS_NET_AUDIO;
 			break;
-		case 3U:
+		case M17_DATA_TYPE_VOICE_DATA:
 			LogMessage("M17, received network voice + data transmission from %s to %s", source.c_str(), dest.c_str());
 			m_netState = RS_NET_AUDIO;
 			break;
@@ -532,7 +479,7 @@ void CM17Control::writeNetwork()
 		m_packetTimer.start();
 		m_elapsed.start();
 		m_netFrames = 0U;
-		m_netLICHn  = 0U;
+		m_netLSFn   = 0U;
 
 		// Create a dummy start message
 		unsigned char start[M17_FRAME_LENGTH_BYTES + 2U];
@@ -543,8 +490,8 @@ void CM17Control::writeNetwork()
 		// Generate the sync
 		CSync::addM17LinkSetupSync(start + 2U);
 
-		unsigned char setup[M17_LICH_LENGTH_BYTES];
-		m_netLICH.getLinkSetup(setup);
+		unsigned char setup[M17_LSF_LENGTH_BYTES];
+		m_netLSF.getLinkSetup(setup);
 
 		// Add the convolution FEC
 		CM17Convolution conv;
@@ -557,66 +504,144 @@ void CM17Control::writeNetwork()
 		writeQueueNet(start);
 	}
 
-	unsigned char data[M17_FRAME_LENGTH_BYTES + 2U];
+	if (m_netState == RS_NET_AUDIO) {
+		unsigned char data[M17_FRAME_LENGTH_BYTES + 2U];
 
-	data[0U] = TAG_DATA;
-	data[1U] = 0x00U;
+		data[0U] = TAG_DATA;
+		data[1U] = 0x00U;
 
-	// Generate the sync
-	CSync::addM17StreamSync(data + 2U);
+		// Generate the sync
+		CSync::addM17StreamSync(data + 2U);
 
-	m_netFrames++;
+		m_netFrames++;
 
-	// Add the fragment LICH
-	unsigned char lich[M17_LICH_FRAGMENT_LENGTH_BYTES];
-	m_netLICH.getFragment(lich, m_netLICHn);
+		// Add the fragment LICH
+		unsigned char lich[M17_LSF_FRAGMENT_LENGTH_BYTES];
+		m_netLSF.getFragment(lich, m_netLSFn);
 
-	unsigned int frag1, frag2, frag3, frag4;
-	CM17Utils::splitFragmentLICH(lich, frag1, frag2, frag3, frag4);
+		unsigned int frag1, frag2, frag3, frag4;
+		CM17Utils::splitFragmentLICH(lich, frag1, frag2, frag3, frag4);
 
-	// Add the Color Code and fragment number
-	frag4 |= (m_netLICHn & 0x07U)  << 4;
-	frag4 |= (m_colorCode & 0x1FU) << 7;
+		// Add the Color Code and fragment number
+		frag4 |= (m_netLSFn & 0x07U) << 4;
+		frag4 |= (m_can & 0x1FU) << 7;
 
-	// Add Golay to the LICH fragment here
-	unsigned int lich1 = CGolay24128::encode24128(frag1);
-	unsigned int lich2 = CGolay24128::encode24128(frag2);
-	unsigned int lich3 = CGolay24128::encode24128(frag3);
-	unsigned int lich4 = CGolay24128::encode24128(frag4);
+		// Add Golay to the LICH fragment here
+		unsigned int lich1 = CGolay24128::encode24128(frag1);
+		unsigned int lich2 = CGolay24128::encode24128(frag2);
+		unsigned int lich3 = CGolay24128::encode24128(frag3);
+		unsigned int lich4 = CGolay24128::encode24128(frag4);
 
-	CM17Utils::combineFragmentLICHFEC(lich1, lich2, lich3, lich4, data + 2U + M17_SYNC_LENGTH_BYTES);
+		CM17Utils::combineFragmentLICHFEC(lich1, lich2, lich3, lich4, data + 2U + M17_SYNC_LENGTH_BYTES);
 
-	// Add the FN and the data/audio
-	unsigned char payload[M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES];
-	::memcpy(payload, netData + 28U, M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES);
+		// Add the FN and the data/audio
+		unsigned char payload[M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES];
+		::memcpy(payload, netData + 28U, M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES);
 
-	// Add the CRC
-	CM17CRC::encodeCRC(payload, M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES);
+		// Add the CRC
+		CM17CRC::encodeCRC(payload, M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES);
 
-	// Add the Convolution FEC
-	CM17Convolution conv;
-	conv.encodeData(payload, data + 2U + M17_SYNC_LENGTH_BYTES + M17_LICH_FRAGMENT_FEC_LENGTH_BYTES);
+		// Add the Convolution FEC
+		CM17Convolution conv;
+		conv.encodeData(payload, data + 2U + M17_SYNC_LENGTH_BYTES + M17_LICH_FRAGMENT_FEC_LENGTH_BYTES);
 
-	unsigned char temp[M17_FRAME_LENGTH_BYTES];
-	interleaver(data + 2U, temp);
-	decorrelator(temp, data + 2U);
+		unsigned char temp[M17_FRAME_LENGTH_BYTES];
+		interleaver(data + 2U, temp);
+		decorrelator(temp, data + 2U);
 
-	writeQueueNet(data);
+		writeQueueNet(data);
 
-	m_netLICHn++;
-	if (m_netLICHn >= 6U)
-		m_netLICHn = 0U;
+		m_netLSFn++;
+		if (m_netLSFn >= 6U)
+			m_netLSFn = 0U;
 
-	// EOT handling
-	uint16_t fn = (netData[28U] << 8) + (netData[29U] << 0);
-	if ((fn & 0x8000U) == 0x8000U) {
-		std::string source = m_netLICH.getSource();
-		std::string dest   = m_netLICH.getDest();
-		LogMessage("M17, received network end of transmission from %s to %s, %.1f seconds", source.c_str(), dest.c_str(), float(m_netFrames) / 25.0F);
-		writeEndNet();
+		// EOT handling
+		uint16_t fn = (netData[28U] << 8) + (netData[29U] << 0);
+		if ((fn & 0x8000U) == 0x8000U) {
+			std::string source = m_netLSF.getSource();
+			std::string dest   = m_netLSF.getDest();
+			LogMessage("M17, received network end of transmission from %s to %s, %.1f seconds", source.c_str(), dest.c_str(), float(m_netFrames) / 25.0F);
+			writeEndNet();
+		}
 	}
 }
 
+bool CM17Control::processRFHeader(bool lateEntry)
+{
+	unsigned char can = m_rfLSF.getCAN();
+	if (can != m_can)
+		return false;
+
+	std::string source = m_rfLSF.getSource();
+	std::string dest   = m_rfLSF.getDest();
+
+	if (!m_allowEncryption) {
+		unsigned char type = m_rfLSF.getEncryptionType();
+		if (type != M17_ENCRYPTION_TYPE_NONE) {
+			LogMessage("M17, access attempt with encryption from %s to %s", source.c_str(), dest.c_str());
+			m_rfState = RS_RF_REJECTED;
+			return false;
+		}
+	}
+
+	if (m_selfOnly) {
+		bool ret = checkCallsign(source);
+		if (!ret) {
+			LogMessage("M17, invalid access attempt from %s to %s", source.c_str(), dest.c_str());
+			m_rfState = RS_RF_REJECTED;
+			return false;
+		}
+	}
+
+	unsigned char dataType = m_rfLSF.getDataType();
+	switch (dataType) {
+	case M17_DATA_TYPE_DATA:
+		LogMessage("M17, received RF%sdata transmission from %s to %s", lateEntry ? " late entry " : " ", source.c_str(), dest.c_str());
+		m_rfState = RS_RF_DATA;
+		break;
+	case M17_DATA_TYPE_VOICE:
+		LogMessage("M17, received RF%svoice transmission from %s to %s", lateEntry ? " late entry " : " ", source.c_str(), dest.c_str());
+		m_rfState = RS_RF_AUDIO;
+		break;
+	case M17_DATA_TYPE_VOICE_DATA:
+		LogMessage("M17, received RF%svoice + data transmission from %s to %s", lateEntry ? " late entry " : " ", source.c_str(), dest.c_str());
+		m_rfState = RS_RF_AUDIO;
+		break;
+	default:
+		LogMessage("M17, received RF%sunknown transmission from %s to %s", lateEntry ? " late entry " : " ", source.c_str(), dest.c_str());
+		m_rfState = RS_RF_DATA;
+		break;
+	}
+
+	m_display->writeM17(source.c_str(), dest.c_str(), "R");
+
+	if (m_duplex) {
+		unsigned char data[M17_FRAME_LENGTH_BYTES + 2U];
+
+		// Create a Link Setup frame
+		data[0U] = TAG_HEADER;
+		data[1U] = 0x00U;
+
+		// Generate the sync
+		CSync::addM17LinkSetupSync(data + 2U);
+
+		unsigned char setup[M17_LSF_LENGTH_BYTES];
+		m_rfLSF.getLinkSetup(setup);
+
+		// Add the convolution FEC
+		CM17Convolution conv;
+		conv.encodeLinkSetup(setup, data + 2U + M17_SYNC_LENGTH_BYTES);
+
+		unsigned char temp[M17_FRAME_LENGTH_BYTES];
+		interleaver(data + 2U, temp);
+		decorrelator(temp, data + 2U);
+
+		writeQueueRF(data);
+	}
+
+	return true;
+}
+
 void CM17Control::clock(unsigned int ms)
 {
 	if (m_network != NULL)
@@ -678,19 +703,6 @@ void CM17Control::writeQueueNet(const unsigned char *data)
 	m_queue.addData(data, len);
 }
 
-void CM17Control::writeNetwork(const unsigned char *data)
-{
-	assert(data != NULL);
-
-	if (m_network == NULL)
-		return;
-
-	if (m_rfTimeoutTimer.isRunning() && m_rfTimeoutTimer.hasExpired())
-		return;
-
-	m_network->write(data);
-}
-
 void CM17Control::interleaver(const unsigned char* in, unsigned char* out) const
 {
 	assert(in != NULL);
diff --git a/M17Control.h b/M17Control.h
index 276478c..9ed515c 100644
--- a/M17Control.h
+++ b/M17Control.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015-2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -24,9 +24,9 @@
 #include "M17Defines.h"
 #include "RingBuffer.h"
 #include "StopWatch.h"
-#include "M17LICH.h"
 #include "Display.h"
 #include "Defines.h"
+#include "M17LSF.h"
 #include "Timer.h"
 #include "Modem.h"
 
@@ -34,7 +34,7 @@
 
 class CM17Control {
 public:
-	CM17Control(const std::string& callsign, unsigned int colorCode, bool selfOnly, bool allowEncryption, CM17Network* network, CDisplay* display, unsigned int timeout, bool duplex, CRSSIInterpolator* rssiMapper);
+	CM17Control(const std::string& callsign, unsigned int can, bool selfOnly, bool allowEncryption, CM17Network* network, CDisplay* display, unsigned int timeout, bool duplex, CRSSIInterpolator* rssiMapper);
 	~CM17Control();
 
 	bool writeModem(unsigned char* data, unsigned int len);
@@ -49,7 +49,7 @@ public:
 
 private:
 	std::string                m_callsign;
-	unsigned int               m_colorCode;
+	unsigned int               m_can;
 	bool                       m_selfOnly;
 	bool                       m_allowEncryption;
 	CM17Network*               m_network;
@@ -68,10 +68,10 @@ private:
 	unsigned int               m_rfFN;
 	unsigned int               m_rfErrs;
 	unsigned int               m_rfBits;
-	CM17LICH                   m_rfLICH;
-	unsigned int               m_rfLICHn;
-	CM17LICH                   m_netLICH;
-	unsigned int               m_netLICHn;
+	CM17LSF                    m_rfLSF;
+	unsigned int               m_rfLSFn;
+	CM17LSF                    m_netLSF;
+	unsigned int               m_netLSFn;
 	CRSSIInterpolator*         m_rssiMapper;
 	unsigned char              m_rssi;
 	unsigned char              m_maxRSSI;
@@ -81,9 +81,10 @@ private:
 	bool                       m_enabled;
 	FILE*                      m_fp;
 
+	bool processRFHeader(bool lateEntry);
+
 	void writeQueueRF(const unsigned char* data);
 	void writeQueueNet(const unsigned char* data);
-	void writeNetwork(const unsigned char* data);
 	void writeNetwork();
 
 	void interleaver(const unsigned char* in, unsigned char* out) const;
diff --git a/M17Convolution.cpp b/M17Convolution.cpp
index 1f64a76..5a83ab0 100644
--- a/M17Convolution.cpp
+++ b/M17Convolution.cpp
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2016,2018,2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
diff --git a/M17Convolution.h b/M17Convolution.h
index e3f5d82..91843ba 100644
--- a/M17Convolution.h
+++ b/M17Convolution.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2018,2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
diff --git a/M17Defines.h b/M17Defines.h
index 2eae167..5dc07f7 100644
--- a/M17Defines.h
+++ b/M17Defines.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2016,2017,2018,2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -31,12 +31,18 @@ const unsigned char M17_PACKET_SYNC_BYTES[]     = {0x75U, 0xFFU};
 const unsigned int  M17_SYNC_LENGTH_BITS  = 16U;
 const unsigned int  M17_SYNC_LENGTH_BYTES = M17_SYNC_LENGTH_BITS / 8U;
 
-const unsigned int M17_LICH_LENGTH_BITS  = 240U;
-const unsigned int M17_LICH_LENGTH_BYTES = M17_LICH_LENGTH_BITS / 8U;
+const unsigned int M17_LSF_LENGTH_BITS  = 240U;
+const unsigned int M17_LSF_LENGTH_BYTES = M17_LSF_LENGTH_BITS / 8U;
 
-const unsigned int M17_LICH_FRAGMENT_LENGTH_BITS  = M17_LICH_LENGTH_BITS / 6U;
+const unsigned int M17_LSF_FRAGMENT_LENGTH_BITS  = M17_LSF_LENGTH_BITS / 6U;
+const unsigned int M17_LSF_FRAGMENT_LENGTH_BYTES = M17_LSF_FRAGMENT_LENGTH_BITS / 8U;
+
+const unsigned int M17_LICH_FRAGMENT_LENGTH_BITS  = M17_LSF_FRAGMENT_LENGTH_BITS + 8U;
 const unsigned int M17_LICH_FRAGMENT_LENGTH_BYTES = M17_LICH_FRAGMENT_LENGTH_BITS / 8U;
 
+const unsigned int M17_LSF_FRAGMENT_FEC_LENGTH_BITS  = M17_LSF_FRAGMENT_LENGTH_BITS * 2U;
+const unsigned int M17_LSF_FRAGMENT_FEC_LENGTH_BYTES = M17_LSF_FRAGMENT_FEC_LENGTH_BITS / 8U;
+
 const unsigned int M17_LICH_FRAGMENT_FEC_LENGTH_BITS  = M17_LICH_FRAGMENT_LENGTH_BITS * 2U;
 const unsigned int M17_LICH_FRAGMENT_FEC_LENGTH_BYTES = M17_LICH_FRAGMENT_FEC_LENGTH_BITS / 8U;
 
@@ -56,4 +62,15 @@ const unsigned int M17_CRC_LENGTH_BYTES = M17_CRC_LENGTH_BITS / 8U;
 const unsigned char M17_3200_SILENCE[] = {0x01U, 0x00U, 0x09U, 0x43U, 0x9CU, 0xE4U, 0x21U, 0x08U};
 const unsigned char M17_1600_SILENCE[] = {0x01U, 0x00U, 0x04U, 0x00U, 0x25U, 0x75U, 0xDDU, 0xF2U};
 
+const unsigned char M17_PACKET_TYPE = 0U;
+const unsigned char M17_STREAM_TYPE = 1U;
+
+const unsigned char M17_DATA_TYPE_DATA       = 0x01U;
+const unsigned char M17_DATA_TYPE_VOICE      = 0x02U;
+const unsigned char M17_DATA_TYPE_VOICE_DATA = 0x03U;
+
+const unsigned char M17_ENCRYPTION_TYPE_NONE     = 0x00U;
+const unsigned char M17_ENCRYPTION_TYPE_AES      = 0x01U;
+const unsigned char M17_ENCRYPTION_TYPE_SCRAMBLE = 0x02U;
+
 #endif
diff --git a/M17LICH.cpp b/M17LICH.cpp
deleted file mode 100644
index e99fd8d..0000000
--- a/M17LICH.cpp
+++ /dev/null
@@ -1,143 +0,0 @@
-/*
- *   Copyright (C) 2020 by Jonathan Naylor G4KLX
- *
- *   This program is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU General Public License as published by
- *   the Free Software Foundation; either version 2 of the License, or
- *   (at your option) any later version.
- *
- *   This program is distributed in the hope that it will be useful,
- *   but WITHOUT ANY WARRANTY; without even the implied warranty of
- *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *   GNU General Public License for more details.
- *
- *   You should have received a copy of the GNU General Public License
- *   along with this program; if not, write to the Free Software
- *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-#include "M17LICH.h"
-#include "M17Utils.h"
-#include "M17Defines.h"
-#include "M17CRC.h"
-
-#include <cassert>
-#include <cstring>
-
-CM17LICH::CM17LICH() :
-m_lich(NULL),
-m_valid(false)
-{
-	m_lich = new unsigned char[M17_LICH_LENGTH_BYTES];
-}
-
-CM17LICH::~CM17LICH()
-{
-	delete[] m_lich;
-}
-
-void CM17LICH::getNetwork(unsigned char* data) const
-{
-	assert(data != NULL);
-
-	::memcpy(data, m_lich, M17_LICH_LENGTH_BYTES);
-}
-
-void CM17LICH::setNetwork(const unsigned char* data)
-{
-	assert(data != NULL);
-
-	::memcpy(m_lich, data, M17_LICH_LENGTH_BYTES);
-
-	m_valid = true;
-}
-
-std::string CM17LICH::getSource() const
-{
-	std::string callsign;
-	CM17Utils::decodeCallsign(m_lich + 6U, callsign);
-
-	return callsign;
-}
-
-void CM17LICH::setSource(const std::string& callsign)
-{
-	CM17Utils::encodeCallsign(callsign, m_lich + 6U);
-}
-
-std::string CM17LICH::getDest() const
-{
-	std::string callsign;
-	CM17Utils::decodeCallsign(m_lich + 0U, callsign);
-
-	return callsign;
-}
-
-void CM17LICH::setDest(const std::string& callsign)
-{
-	CM17Utils::encodeCallsign(callsign, m_lich + 0U);
-}
-
-unsigned char CM17LICH::getDataType() const
-{
-	return (m_lich[13U] >> 1) & 0x03U;
-}
-
-void CM17LICH::setDataType(unsigned char type)
-{
-	m_lich[13U] &= 0xF9U;
-	m_lich[13U] |= (type << 1) & 0x06U;
-}
-
-bool CM17LICH::isNONCENull() const
-{
-	return ::memcmp(m_lich + 14U, M17_NULL_NONCE, M17_NONCE_LENGTH_BYTES) == 0;
-}
-
-void CM17LICH::reset()
-{
-	::memset(m_lich, 0x00U, 30U);
-
-	m_valid = false;
-}
-
-bool CM17LICH::isValid() const
-{
-	return m_valid;
-}
-
-void CM17LICH::getLinkSetup(unsigned char* data) const
-{
-	assert(data != NULL);
-
-	::memcpy(data, m_lich, M17_LICH_LENGTH_BYTES);
-
-	CM17CRC::encodeCRC(data, M17_LICH_LENGTH_BYTES);
-}
-
-void CM17LICH::setLinkSetup(const unsigned char* data)
-{
-	assert(data != NULL);
-
-	::memcpy(m_lich, data, M17_LICH_LENGTH_BYTES);
-
-	m_valid = CM17CRC::checkCRC(m_lich, M17_LICH_LENGTH_BYTES);
-}
-
-void CM17LICH::getFragment(unsigned char* data, unsigned int n) const
-{
-	assert(data != NULL);
-
-	CM17CRC::encodeCRC(m_lich, M17_LICH_LENGTH_BYTES);
-
-	::memcpy(data, m_lich + (n * M17_LICH_FRAGMENT_LENGTH_BYTES), M17_LICH_FRAGMENT_LENGTH_BYTES);
-}
-
-void CM17LICH::setFragment(const unsigned char* data, unsigned int n)
-{
-	assert(data != NULL);
-
-	::memcpy(m_lich + (n * M17_LICH_FRAGMENT_LENGTH_BYTES), data, M17_LICH_FRAGMENT_LENGTH_BYTES);
-
-	m_valid = CM17CRC::checkCRC(m_lich, M17_LICH_LENGTH_BYTES);
-}
diff --git a/M17LSF.cpp b/M17LSF.cpp
new file mode 100644
index 0000000..4d48f40
--- /dev/null
+++ b/M17LSF.cpp
@@ -0,0 +1,193 @@
+/*
+ *   Copyright (C) 2020,2021 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "M17LSF.h"
+#include "M17Utils.h"
+#include "M17Defines.h"
+#include "M17CRC.h"
+
+#include <cassert>
+#include <cstring>
+
+CM17LSF::CM17LSF() :
+m_lsf(NULL),
+m_valid(false)
+{
+	m_lsf = new unsigned char[M17_LSF_LENGTH_BYTES];
+}
+
+CM17LSF::~CM17LSF()
+{
+	delete[] m_lsf;
+}
+
+void CM17LSF::getNetwork(unsigned char* data) const
+{
+	assert(data != NULL);
+
+	::memcpy(data, m_lsf, M17_LSF_LENGTH_BYTES);
+}
+
+void CM17LSF::setNetwork(const unsigned char* data)
+{
+	assert(data != NULL);
+
+	::memcpy(m_lsf, data, M17_LSF_LENGTH_BYTES);
+
+	m_valid = true;
+}
+
+std::string CM17LSF::getSource() const
+{
+	if (m_lsf[6U] == 0xFFU && m_lsf[7U]  == 0xFFU && m_lsf[8U]  == 0xFFU &&
+		m_lsf[9U] == 0xFFU && m_lsf[10U] == 0xFFU && m_lsf[11U] == 0xFFU)
+		return "******";
+
+	std::string callsign;
+	CM17Utils::decodeCallsign(m_lsf + 6U, callsign);
+
+	return callsign;
+}
+
+void CM17LSF::setSource(const std::string& callsign)
+{
+	CM17Utils::encodeCallsign(callsign, m_lsf + 6U);
+}
+
+std::string CM17LSF::getDest() const
+{
+	if (m_lsf[0U] == 0xFFU && m_lsf[1U] == 0xFFU && m_lsf[2U] == 0xFFU &&
+		m_lsf[3U] == 0xFFU && m_lsf[4U] == 0xFFU && m_lsf[5U] == 0xFFU)
+		return "******";
+
+	std::string callsign;
+	CM17Utils::decodeCallsign(m_lsf + 0U, callsign);
+
+	return callsign;
+}
+
+void CM17LSF::setDest(const std::string& callsign)
+{
+	CM17Utils::encodeCallsign(callsign, m_lsf + 0U);
+}
+
+unsigned char CM17LSF::getPacketStream() const
+{
+	return m_lsf[13U] & 0x01U;
+}
+
+void CM17LSF::setPacketStream(unsigned char ps)
+{
+	m_lsf[13U] &= 0xF7U;
+	m_lsf[13U] |= ps & 0x01U;
+}
+
+unsigned char CM17LSF::getDataType() const
+{
+	return (m_lsf[13U] >> 1) & 0x03U;
+}
+
+void CM17LSF::setDataType(unsigned char type)
+{
+	m_lsf[13U] &= 0xF9U;
+	m_lsf[13U] |= (type << 1) & 0x06U;
+}
+
+unsigned char CM17LSF::getEncryptionType() const
+{
+	return (m_lsf[13U] >> 3) & 0x03U;
+}
+
+void CM17LSF::setEncryptionType(unsigned char type)
+{
+	m_lsf[13U] &= 0xE7U;
+	m_lsf[13U] |= (type << 3) & 0x18U;
+}
+
+unsigned char CM17LSF::getEncryptionSubType() const
+{
+	return (m_lsf[13U] >> 5) & 0x03U;
+}
+
+void CM17LSF::setEncryptionSubType(unsigned char type)
+{
+	m_lsf[13U] &= 0x9FU;
+	m_lsf[13U] |= (type << 5) & 0x60U;
+}
+
+unsigned char CM17LSF::getCAN() const
+{
+	return ((m_lsf[12U] << 1) & 0x0EU) | ((m_lsf[13U] >> 7) & 0x01U);
+}
+
+void CM17LSF::setCAN(unsigned char can)
+{
+	m_lsf[13U] &= 0x7FU;
+	m_lsf[13U] |= (can << 7) & 0x80U;
+
+	m_lsf[12U] &= 0xF8U;
+	m_lsf[12U] |= (can >> 1) & 0x07U;
+}
+
+void CM17LSF::reset()
+{
+	::memset(m_lsf, 0x00U, 30U);
+
+	m_valid = false;
+}
+
+bool CM17LSF::isValid() const
+{
+	return m_valid;
+}
+
+void CM17LSF::getLinkSetup(unsigned char* data) const
+{
+	assert(data != NULL);
+
+	::memcpy(data, m_lsf, M17_LSF_LENGTH_BYTES);
+
+	CM17CRC::encodeCRC(data, M17_LSF_LENGTH_BYTES);
+}
+
+void CM17LSF::setLinkSetup(const unsigned char* data)
+{
+	assert(data != NULL);
+
+	::memcpy(m_lsf, data, M17_LSF_LENGTH_BYTES);
+
+	m_valid = CM17CRC::checkCRC(m_lsf, M17_LSF_LENGTH_BYTES);
+}
+
+void CM17LSF::getFragment(unsigned char* data, unsigned int n) const
+{
+	assert(data != NULL);
+
+	CM17CRC::encodeCRC(m_lsf, M17_LSF_LENGTH_BYTES);
+
+	::memcpy(data, m_lsf + (n * M17_LSF_FRAGMENT_LENGTH_BYTES), M17_LSF_FRAGMENT_LENGTH_BYTES);
+}
+
+void CM17LSF::setFragment(const unsigned char* data, unsigned int n)
+{
+	assert(data != NULL);
+
+	::memcpy(m_lsf + (n * M17_LSF_FRAGMENT_LENGTH_BYTES), data, M17_LSF_FRAGMENT_LENGTH_BYTES);
+
+	m_valid = CM17CRC::checkCRC(m_lsf, M17_LSF_LENGTH_BYTES);
+}
diff --git a/M17LICH.h b/M17LSF.h
similarity index 73%
rename from M17LICH.h
rename to M17LSF.h
index 804de3e..a12c1fe 100644
--- a/M17LICH.h
+++ b/M17LSF.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -16,15 +16,15 @@
  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
-#if !defined(M17LICH_H)
-#define  M17LICH_H
+#if !defined(M17LSF_H)
+#define  M17LSF_H
 
 #include <string>
 
-class CM17LICH {
+class CM17LSF {
 public:
-	CM17LICH();
-	~CM17LICH();
+	CM17LSF();
+	~CM17LSF();
 
 	void getNetwork(unsigned char* data) const;
 	void setNetwork(const unsigned char* data);
@@ -35,10 +35,20 @@ public:
 	std::string getDest() const;
 	void setDest(const std::string& callsign);
 
+	unsigned char getPacketStream() const;
+	void setPacketStream(unsigned char ps);
+
 	unsigned char getDataType() const;
 	void setDataType(unsigned char type);
 
-	bool isNONCENull() const;
+	unsigned char getEncryptionType() const;
+	void setEncryptionType(unsigned char type);
+
+	unsigned char getEncryptionSubType() const;
+	void setEncryptionSubType(unsigned char type);
+
+	unsigned char getCAN() const;
+	void setCAN(unsigned char can);
 
 	void reset();
 	bool isValid() const;
@@ -50,7 +60,7 @@ public:
 	void setFragment(const unsigned char* data, unsigned int n);
 
 private:
-	unsigned char* m_lich;
+	unsigned char* m_lsf;
 	bool           m_valid;
 };
 
diff --git a/M17Network.cpp b/M17Network.cpp
index 56a2135..2fd213d 100644
--- a/M17Network.cpp
+++ b/M17Network.cpp
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2014,2016,2019,2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
diff --git a/M17Network.h b/M17Network.h
index e65e1f3..9fc555a 100644
--- a/M17Network.h
+++ b/M17Network.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2014,2016,2018,2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
diff --git a/M17Utils.cpp b/M17Utils.cpp
index 1ba33b1..5a22adf 100644
--- a/M17Utils.cpp
+++ b/M17Utils.cpp
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -60,12 +60,13 @@ void CM17Utils::decodeCallsign(const unsigned char* encoded, std::string& callsi
 
 	callsign.clear();
 
-	uint64_t enc = (uint64_t(encoded[0U]) << 40) +
-		       (uint64_t(encoded[1U]) << 32) +
-		       (uint64_t(encoded[2U]) << 24) +
-		       (uint64_t(encoded[3U]) << 16) +
-		       (uint64_t(encoded[4U]) << 8)  +
-		       (uint64_t(encoded[5U]) << 0);
+	uint64_t enc =
+			(uint64_t(encoded[0U]) << 40) +
+			(uint64_t(encoded[1U]) << 32) +
+			(uint64_t(encoded[2U]) << 24) +
+			(uint64_t(encoded[3U]) << 16) +
+			(uint64_t(encoded[4U]) << 8) +
+			(uint64_t(encoded[5U]) << 0);
 
 	if (enc >= 262144000000000ULL)	// 40^9
 		return;
diff --git a/MMDVM.ini b/MMDVM.ini
index be1dbcf..b4fe1e1 100644
--- a/MMDVM.ini
+++ b/MMDVM.ini
@@ -149,7 +149,7 @@ TXHang=5
 
 [M17]
 Enable=1
-ColorCode=3
+CAN=0
 SelfOnly=0
 TXHang=5
 # ModeHang=10
diff --git a/MMDVMHost.cpp b/MMDVMHost.cpp
index 592531a..b21870a 100644
--- a/MMDVMHost.cpp
+++ b/MMDVMHost.cpp
@@ -634,19 +634,19 @@ int CMMDVMHost::run()
 
 	if (m_m17Enabled) {
 		bool selfOnly          = m_conf.getM17SelfOnly();
-		unsigned int colorCode = m_conf.getM17ColorCode();
+		unsigned int can       = m_conf.getM17CAN();
 		bool allowEncryption   = m_conf.getM17AllowEncryption();
 		unsigned int txHang    = m_conf.getM17TXHang();
 		m_m17RFModeHang        = m_conf.getM17ModeHang();
 
 		LogInfo("M17 RF Parameters");
 		LogInfo("    Self Only: %s", selfOnly ? "yes" : "no");
-		LogInfo("    Color Code: %u", colorCode);
+		LogInfo("    CAN: %u", can);
 		LogInfo("    Allow Encryption: %s", allowEncryption ? "yes" : "no");
 		LogInfo("    TX Hang: %us", txHang);
 		LogInfo("    Mode Hang: %us", m_m17RFModeHang);
 
-		m_m17 = new CM17Control(m_callsign, colorCode, selfOnly, allowEncryption, m_m17Network, m_display, m_timeout, m_duplex, rssi);
+		m_m17 = new CM17Control(m_callsign, can, selfOnly, allowEncryption, m_m17Network, m_display, m_timeout, m_duplex, rssi);
 	}
 
 	CTimer pocsagTimer(1000U, 30U);
diff --git a/MMDVMHost.vcxproj b/MMDVMHost.vcxproj
index 182f62a..bebf213 100644
--- a/MMDVMHost.vcxproj
+++ b/MMDVMHost.vcxproj
@@ -199,7 +199,7 @@
     <ClInclude Include="M17Convolution.h" />
     <ClInclude Include="M17CRC.h" />
     <ClInclude Include="M17Defines.h" />
-    <ClInclude Include="M17LICH.h" />
+    <ClInclude Include="M17LSF.h" />
     <ClInclude Include="M17Network.h" />
     <ClInclude Include="M17Utils.h" />
     <ClInclude Include="MMDVMHost.h" />
@@ -308,7 +308,7 @@
     <ClCompile Include="M17Control.cpp" />
     <ClCompile Include="M17Convolution.cpp" />
     <ClCompile Include="M17CRC.cpp" />
-    <ClCompile Include="M17LICH.cpp" />
+    <ClCompile Include="M17LSF.cpp" />
     <ClCompile Include="M17Network.cpp" />
     <ClCompile Include="M17Utils.cpp" />
     <ClCompile Include="MMDVMHost.cpp" />
diff --git a/MMDVMHost.vcxproj.filters b/MMDVMHost.vcxproj.filters
index 36320cd..77f0c68 100644
--- a/MMDVMHost.vcxproj.filters
+++ b/MMDVMHost.vcxproj.filters
@@ -296,7 +296,7 @@
     <ClInclude Include="M17Network.h">
       <Filter>Header Files</Filter>
     </ClInclude>
-    <ClInclude Include="M17LICH.h">
+    <ClInclude Include="M17LSF.h">
       <Filter>Header Files</Filter>
     </ClInclude>
     <ClInclude Include="M17CRC.h">
@@ -610,7 +610,7 @@
     <ClCompile Include="M17Utils.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
-    <ClCompile Include="M17LICH.cpp">
+    <ClCompile Include="M17LSF.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
     <ClCompile Include="M17Convolution.cpp">
diff --git a/Makefile b/Makefile
index 901697a..fa6b777 100644
--- a/Makefile
+++ b/Makefile
@@ -10,7 +10,7 @@ OBJECTS = \
 		AMBEFEC.o BCH.o AX25Control.o AX25Network.o BPTC19696.o CASTInfo.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o \
 		DMRDirectNetwork.o DMREMB.o DMREmbeddedData.o DMRFullLC.o DMRGatewayNetwork.o DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o \
 		DMRAccessControl.o DMRTA.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o \
-		Hamming.o I2CController.o IIRDirectForm1Filter.o LCDproc.o Log.o M17Control.o M17Convolution.o M17CRC.o M17LICH.o M17Network.o M17Utils.o MMDVMHost.o \
+		Hamming.o I2CController.o IIRDirectForm1Filter.o LCDproc.o Log.o M17Control.o M17Convolution.o M17CRC.o M17LSF.o M17Network.o M17Utils.o MMDVMHost.o \
 		Modem.o ModemPort.o ModemSerialPort.o Mutex.o NetworkInfo.o Nextion.o NullController.o NullDisplay.o NXDNAudio.o NXDNControl.o \
 		NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNIcomNetwork.o NXDNKenwoodNetwork.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 PseudoTTYController.o POCSAGControl.o \
diff --git a/Makefile.Pi b/Makefile.Pi
index 528c972..c0ab7f6 100644
--- a/Makefile.Pi
+++ b/Makefile.Pi
@@ -10,7 +10,7 @@ OBJECTS = \
 		AMBEFEC.o AX25Control.o AX25Network.o BCH.o BPTC19696.o CASTInfo.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o \
 		DMRDirectNetwork.o DMREMB.o DMREmbeddedData.o DMRFullLC.o DMRGatewayNetwork.o DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o \
 		DMRAccessControl.o DMRTA.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o \
-		Hamming.o I2CController.o IIRDirectForm1Filter.o LCDproc.o Log.o M17Control.o M17Convolution.o M17CRC.o M17LICH.o M17Network.o M17Utils.o MMDVMHost.o \
+		Hamming.o I2CController.o IIRDirectForm1Filter.o LCDproc.o Log.o M17Control.o M17Convolution.o M17CRC.o M17LSF.o M17Network.o M17Utils.o MMDVMHost.o \
 		Modem.o ModemPort.o ModemSerialPort.o Mutex.o NetworkInfo.o Nextion.o NullController.o NullDisplay.o NXDNAudio.o NXDNControl.o \
 		NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNIcomNetwork.o NXDNKenwoodNetwork.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 PseudoTTYController.o POCSAGControl.o \
diff --git a/Makefile.Pi.Adafruit b/Makefile.Pi.Adafruit
index d4e75dd..a0538a1 100644
--- a/Makefile.Pi.Adafruit
+++ b/Makefile.Pi.Adafruit
@@ -11,7 +11,7 @@ OBJECTS = \
 		AMBEFEC.o AX25Control.o AX25Network.o BCH.o BPTC19696.o CASTInfo.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o \
 		DMRDirectNetwork.o DMREMB.o DMREmbeddedData.o DMRFullLC.o DMRGatewayNetwork.o DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o \
 		DMRAccessControl.o DMRTA.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o \
-		Hamming.o HD44780.o I2CController.o IIRDirectForm1Filter.o LCDproc.o Log.o M17Control.o M17Convolution.o M17CRC.o M17LICH.o M17Network.o M17Utils.o \
+		Hamming.o HD44780.o I2CController.o IIRDirectForm1Filter.o LCDproc.o Log.o M17Control.o M17Convolution.o M17CRC.o M17LSF.o M17Network.o M17Utils.o \
 		MMDVMHost.o Modem.o ModemPort.o ModemSerialPort.o Mutex.o NetworkInfo.o Nextion.o NullController.o NullDisplay.o NXDNAudio.o \
 		NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNIcomNetwork.o NXDNKenwoodNetwork.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 PseudoTTYController.o \
diff --git a/Makefile.Pi.HD44780 b/Makefile.Pi.HD44780
index 215d9f1..3885dc3 100644
--- a/Makefile.Pi.HD44780
+++ b/Makefile.Pi.HD44780
@@ -10,7 +10,7 @@ OBJECTS = \
 		AMBEFEC.o AX25Control.o AX25Network.o BCH.o BPTC19696.o CASTInfo.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o \
 		DMRDirectNetwork.o DMREMB.o DMREmbeddedData.o DMRFullLC.o DMRGatewayNetwork.o DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o \
 		DMRAccessControl.o DMRTA.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o \
-		Hamming.o HD44780.o I2CController.o IIRDirectForm1Filter.o LCDproc.o Log.o M17Control.o M17Convolution.o M17CRC.o M17LICH.o M17Network.o M17Utils.o \
+		Hamming.o HD44780.o I2CController.o IIRDirectForm1Filter.o LCDproc.o Log.o M17Control.o M17Convolution.o M17CRC.o M17LSF.o M17Network.o M17Utils.o \
 		MMDVMHost.o Modem.o ModemPort.o ModemSerialPort.o Mutex.o NetworkInfo.o Nextion.o NullController.o NullDisplay.o NXDNAudio.o \
 		NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNIcomNetwork.o NXDNKenwoodNetwork.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 PseudoTTYController.o \
diff --git a/Makefile.Pi.OLED b/Makefile.Pi.OLED
index 889c72d..ab99eb2 100644
--- a/Makefile.Pi.OLED
+++ b/Makefile.Pi.OLED
@@ -14,7 +14,7 @@ OBJECTS = \
 		AMBEFEC.o AX25Control.o AX25Network.o BCH.o BPTC19696.o CASTInfo.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o \
 		DMRDirectNetwork.o DMREMB.o DMREmbeddedData.o DMRFullLC.o DMRGatewayNetwork.o DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o \
 		DMRAccessControl.o DMRTA.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o \
-		Hamming.o I2CController.o IIRDirectForm1Filter.o LCDproc.o Log.o M17Control.o M17Convolution.o M17CRC.o M17LICH.o M17Network.o M17Utils.o MMDVMHost.o \
+		Hamming.o I2CController.o IIRDirectForm1Filter.o LCDproc.o Log.o M17Control.o M17Convolution.o M17CRC.o M17LSF.o M17Network.o M17Utils.o MMDVMHost.o \
 		Modem.o ModemPort.o ModemSerialPort.o Mutex.o NetworkInfo.o Nextion.o NullController.o NullDisplay.o NXDNAudio.o NXDNControl.o \
 		NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNIcomNetwork.o NXDNKenwoodNetwork.o NXDNLayer3.o NXDNLICH.o NXDNLookup.o NXDNNetwork.o NXDNSACCH.o \
 		NXDNUDCH.o OLED.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o P25Trellis.o P25Utils.o PseudoTTYController.o \
diff --git a/Makefile.Pi.PCF8574 b/Makefile.Pi.PCF8574
index ce09839..2fff7d9 100644
--- a/Makefile.Pi.PCF8574
+++ b/Makefile.Pi.PCF8574
@@ -11,7 +11,7 @@ OBJECTS = \
 		AMBEFEC.o AX25Control.o AX25Network.o BCH.o BPTC19696.o CASTInfo.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o \
 		DMRDirectNetwork.o DMREMB.o DMREmbeddedData.o DMRFullLC.o DMRGatewayNetwork.o DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o \
 		DMRAccessControl.o DMRTA.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o \
-		Hamming.o HD44780.o I2CController.o IIRDirectForm1Filter.o LCDproc.o Log.o M17Control.o M17Convolution.o M17CRC.o M17LICH.o M17Network.o M17Utils.o \
+		Hamming.o HD44780.o I2CController.o IIRDirectForm1Filter.o LCDproc.o Log.o M17Control.o M17Convolution.o M17CRC.o M17LSF.o M17Network.o M17Utils.o \
 		MMDVMHost.o Modem.o ModemPort.o ModemSerialPort.o Mutex.o NetworkInfo.o Nextion.o NullController.o NullDisplay.o NXDNAudio.o \
 		NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNIcomNetwork.o NXDNKenwoodNetwork.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 PseudoTTYController.o \
diff --git a/Version.h b/Version.h
index 028594f..31bfcac 100644
--- a/Version.h
+++ b/Version.h
@@ -19,6 +19,6 @@
 #if !defined(VERSION_H)
 #define	VERSION_H
 
-const char* VERSION = "20210314";
+const char* VERSION = "20210325";
 
 #endif

From 242cf502403b6647d6a8af81cd96aaf490b5dd32 Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Fri, 26 Mar 2021 20:34:08 +0000
Subject: [PATCH 14/23] Remove the CAN processing from the LICH.

---
 M17Control.cpp | 10 ++--------
 Version.h      |  2 +-
 2 files changed, 3 insertions(+), 9 deletions(-)

diff --git a/M17Control.cpp b/M17Control.cpp
index 5ab306e..37e2c2e 100644
--- a/M17Control.cpp
+++ b/M17Control.cpp
@@ -213,10 +213,6 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		unsigned int lich3 = CGolay24128::decode24128(frag3);
 		unsigned int lich4 = CGolay24128::decode24128(frag4);
 
-		unsigned int can = lich4 & 0x1FU;
-		if (can != m_can)
-			return false;
-
 		unsigned char lich[M17_LICH_FRAGMENT_LENGTH_BYTES];
 		CM17Utils::combineFragmentLICH(lich1, lich2, lich3, lich4, lich);
 
@@ -300,9 +296,8 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		unsigned int frag1, frag2, frag3, frag4;
 		CM17Utils::splitFragmentLICH(lich, frag1, frag2, frag3, frag4);
 
-		// Add the CAN and fragment number
+		// Add the fragment number
 		frag4 |= (m_rfLSFn & 0x07U) << 5;
-		frag4 |= m_can & 0x1FU;
 
 		// Add Golay to the LICH fragment here
 		unsigned int lich1 = CGolay24128::encode24128(frag1);
@@ -522,9 +517,8 @@ void CM17Control::writeNetwork()
 		unsigned int frag1, frag2, frag3, frag4;
 		CM17Utils::splitFragmentLICH(lich, frag1, frag2, frag3, frag4);
 
-		// Add the Color Code and fragment number
+		// Add the fragment number
 		frag4 |= (m_netLSFn & 0x07U) << 4;
-		frag4 |= (m_can & 0x1FU) << 7;
 
 		// Add Golay to the LICH fragment here
 		unsigned int lich1 = CGolay24128::encode24128(frag1);
diff --git a/Version.h b/Version.h
index 31bfcac..564260a 100644
--- a/Version.h
+++ b/Version.h
@@ -19,6 +19,6 @@
 #if !defined(VERSION_H)
 #define	VERSION_H
 
-const char* VERSION = "20210325";
+const char* VERSION = "20210326";
 
 #endif

From 0a94b0deb66ce838a78bc43c5775d5f9be7bfbb4 Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Fri, 26 Mar 2021 22:21:20 +0000
Subject: [PATCH 15/23] Add the LICH CRC.

---
 M17CRC.cpp     | 75 ++++++++++++++++++++++++++++++++++++++++++++------
 M17CRC.h       | 12 +++++---
 M17Control.cpp | 36 ++++++++++++++----------
 M17LSF.cpp     |  8 +++---
 4 files changed, 101 insertions(+), 30 deletions(-)

diff --git a/M17CRC.cpp b/M17CRC.cpp
index cd41697..695511e 100644
--- a/M17CRC.cpp
+++ b/M17CRC.cpp
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -21,7 +21,7 @@
 #include <cstdio>
 #include <cassert>
 
-const uint16_t CRC_TABLE[] = {0x0000U, 0x5935U, 0xB26AU, 0xEB5FU, 0x3DE1U, 0x64D4U, 0x8F8BU, 0xD6BEU, 0x7BC2U, 0x22F7U, 0xC9A8U,
+const uint16_t CRC16_TABLE[] = {0x0000U, 0x5935U, 0xB26AU, 0xEB5FU, 0x3DE1U, 0x64D4U, 0x8F8BU, 0xD6BEU, 0x7BC2U, 0x22F7U, 0xC9A8U,
 			       0x909DU, 0x4623U, 0x1F16U, 0xF449U, 0xAD7CU, 0xF784U, 0xAEB1U, 0x45EEU, 0x1CDBU, 0xCA65U, 0x9350U,
 			       0x780FU, 0x213AU, 0x8C46U, 0xD573U, 0x3E2CU, 0x6719U, 0xB1A7U, 0xE892U, 0x03CDU, 0x5AF8U, 0xB63DU,
 			       0xEF08U, 0x0457U, 0x5D62U, 0x8BDCU, 0xD2E9U, 0x39B6U, 0x6083U, 0xCDFFU, 0x94CAU, 0x7F95U, 0x26A0U,
@@ -46,12 +46,30 @@ const uint16_t CRC_TABLE[] = {0x0000U, 0x5935U, 0xB26AU, 0xEB5FU, 0x3DE1U, 0x64D
 			       0xAC02U, 0xF537U, 0x2389U, 0x7ABCU, 0x91E3U, 0xC8D6U, 0x65AAU, 0x3C9FU, 0xD7C0U, 0x8EF5U, 0x584BU,
 			       0x017EU, 0xEA21U, 0xB314U};
 
-bool CM17CRC::checkCRC(const unsigned char* in, unsigned int nBytes)
+const uint8_t CRC4_TABLE[] = {
+					0x0, 0x7, 0xe, 0x9, 0x5, 0x2, 0xb, 0xc, 0xa, 0xd, 0x4, 0x3, 0xf, 0x8, 0x1, 0x6,
+					0xd, 0xa, 0x3, 0x4, 0x8, 0xf, 0x6, 0x1, 0x7, 0x0, 0x9, 0xe, 0x2, 0x5, 0xc, 0xb,
+					0x3, 0x4, 0xd, 0xa, 0x6, 0x1, 0x8, 0xf, 0x9, 0xe, 0x7, 0x0, 0xc, 0xb, 0x2, 0x5,
+					0xe, 0x9, 0x0, 0x7, 0xb, 0xc, 0x5, 0x2, 0x4, 0x3, 0xa, 0xd, 0x1, 0x6, 0xf, 0x8,
+					0x6, 0x1, 0x8, 0xf, 0x3, 0x4, 0xd, 0xa, 0xc, 0xb, 0x2, 0x5, 0x9, 0xe, 0x7, 0x0,
+					0xb, 0xc, 0x5, 0x2, 0xe, 0x9, 0x0, 0x7, 0x1, 0x6, 0xf, 0x8, 0x4, 0x3, 0xa, 0xd,
+					0x5, 0x2, 0xb, 0xc, 0x0, 0x7, 0xe, 0x9, 0xf, 0x8, 0x1, 0x6, 0xa, 0xd, 0x4, 0x3,
+					0x8, 0xf, 0x6, 0x1, 0xd, 0xa, 0x3, 0x4, 0x2, 0x5, 0xc, 0xb, 0x7, 0x0, 0x9, 0xe,
+					0xc, 0xb, 0x2, 0x5, 0x9, 0xe, 0x7, 0x0, 0x6, 0x1, 0x8, 0xf, 0x3, 0x4, 0xd, 0xa,
+					0x1, 0x6, 0xf, 0x8, 0x4, 0x3, 0xa, 0xd, 0xb, 0xc, 0x5, 0x2, 0xe, 0x9, 0x0, 0x7,
+					0xf, 0x8, 0x1, 0x6, 0xa, 0xd, 0x4, 0x3, 0x5, 0x2, 0xb, 0xc, 0x0, 0x7, 0xe, 0x9,
+					0x2, 0x5, 0xc, 0xb, 0x7, 0x0, 0x9, 0xe, 0x8, 0xf, 0x6, 0x1, 0xd, 0xa, 0x3, 0x4,
+					0xa, 0xd, 0x4, 0x3, 0xf, 0x8, 0x1, 0x6, 0x0, 0x7, 0xe, 0x9, 0x5, 0x2, 0xb, 0xc,
+					0x7, 0x0, 0x9, 0xe, 0x2, 0x5, 0xc, 0xb, 0xd, 0xa, 0x3, 0x4, 0x8, 0xf, 0x6, 0x1,
+					0x9, 0xe, 0x7, 0x0, 0xc, 0xb, 0x2, 0x5, 0x3, 0x4, 0xd, 0xa, 0x6, 0x1, 0x8, 0xf,
+					0x4, 0x3, 0xa, 0xd, 0x1, 0x6, 0xf, 0x8, 0xe, 0x9, 0x0, 0x7, 0xb, 0xc, 0x5, 0x2};
+
+bool CM17CRC::checkCRC16(const unsigned char* in, unsigned int nBytes)
 {
 	assert(in != NULL);
 	assert(nBytes > 2U);
 
-	uint16_t crc = createCRC(in, nBytes - 2U);
+	uint16_t crc = createCRC16(in, nBytes - 2U);
 
 	uint8_t temp[2U];
 	temp[0U] = (crc >> 8) & 0xFFU;
@@ -60,26 +78,67 @@ bool CM17CRC::checkCRC(const unsigned char* in, unsigned int nBytes)
 	return temp[0U] == in[nBytes - 2U] && temp[1U] == in[nBytes - 1U];
 }
 
-void CM17CRC::encodeCRC(unsigned char* in, unsigned int nBytes)
+void CM17CRC::encodeCRC16(unsigned char* in, unsigned int nBytes)
 {
 	assert(in != NULL);
 	assert(nBytes > 2U);
 
-	uint16_t crc = createCRC(in, nBytes - 2U);
+	uint16_t crc = createCRC16(in, nBytes - 2U);
 
 	in[nBytes - 2U] = (crc >> 8) & 0xFFU;
 	in[nBytes - 1U] = (crc >> 0) & 0xFFU;
 }
 
-uint16_t CM17CRC::createCRC(const unsigned char* in, unsigned int nBytes)
+uint16_t CM17CRC::createCRC16(const unsigned char* in, unsigned int nBytes)
 {
 	assert(in != NULL);
 
 	uint16_t crc = 0xFFFFU;
 
 	for (unsigned int i = 0U; i < nBytes; i++)
-		crc = (crc << 8) ^ CRC_TABLE[((crc >> 8) ^ uint16_t(in[i])) & 0x00FFU];
+		crc = (crc << 8) ^ CRC16_TABLE[((crc >> 8) ^ uint16_t(in[i])) & 0x00FFU];
 
 	return crc;
 }
 
+bool CM17CRC::checkCRC8(unsigned char* in, unsigned int nBytes)
+{
+	assert(in != NULL);
+	assert(nBytes > 1U);
+
+	uint8_t save = in[nBytes - 1U] & 0x0FU;
+
+	// Mask out the 4-bit CRC location
+	in[nBytes - 1U] &= 0xF0U;
+
+	uint8_t crc = createCRC8(in, nBytes);
+
+	// Restore the original CRC
+	in[nBytes - 1U] |= save;
+
+	return save == crc;
+}
+
+void CM17CRC::encodeCRC8(unsigned char* in, unsigned int nBytes)
+{
+	assert(in != NULL);
+	assert(nBytes > 1U);
+
+	in[nBytes - 1U] &= 0xF0U;
+
+	uint8_t crc = createCRC8(in, nBytes);
+
+	in[nBytes - 1U] |= crc & 0x0FU;
+}
+
+uint8_t CM17CRC::createCRC8(const unsigned char* in, unsigned int nBytes)
+{
+	assert(in != NULL);
+
+	uint8_t crc = 0x0FU;
+
+	for (unsigned int i = 0U; i < nBytes; i++)
+		crc = CRC4_TABLE[crc ^ in[i]];
+
+	return crc;
+}
diff --git a/M17CRC.h b/M17CRC.h
index 22c8f31..5bc33bb 100644
--- a/M17CRC.h
+++ b/M17CRC.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -24,11 +24,15 @@
 class CM17CRC
 {
 public:
-	static bool checkCRC(const unsigned char* in, unsigned int nBytes);
-	static void encodeCRC(unsigned char* in, unsigned int nBytes);
+	static bool checkCRC16(const unsigned char* in, unsigned int nBytes);
+	static void encodeCRC16(unsigned char* in, unsigned int nBytes);
+
+	static bool checkCRC8(unsigned char* in, unsigned int nBytes);
+	static void encodeCRC8(unsigned char* in, unsigned int nBytes);
 
 private:
-	static uint16_t createCRC(const unsigned char* in, unsigned int nBytes);
+	static uint16_t createCRC16(const unsigned char* in, unsigned int nBytes);
+	static uint8_t  createCRC8(const unsigned char* in, unsigned int nBytes);
 };
 
 #endif
diff --git a/M17Control.cpp b/M17Control.cpp
index 37e2c2e..10238ce 100644
--- a/M17Control.cpp
+++ b/M17Control.cpp
@@ -169,7 +169,7 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		unsigned char frame[M17_LSF_LENGTH_BYTES];
 		conv.decodeLinkSetup(data + 2U + M17_SYNC_LENGTH_BYTES, frame);
 
-		bool valid = CM17CRC::checkCRC(frame, M17_LSF_LENGTH_BYTES);
+		bool valid = CM17CRC::checkCRC16(frame, M17_LSF_LENGTH_BYTES);
 		if (valid) {
 			m_rfLSF.setLinkSetup(frame);
 
@@ -196,6 +196,7 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 			return true;
 		} else {
 			m_rfState = RS_RF_LATE_ENTRY;
+			return false;
 		}
 	}
 
@@ -216,6 +217,9 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		unsigned char lich[M17_LICH_FRAGMENT_LENGTH_BYTES];
 		CM17Utils::combineFragmentLICH(lich1, lich2, lich3, lich4, lich);
 
+		if (!CM17CRC::checkCRC8(lich, M17_LICH_FRAGMENT_LENGTH_BYTES))
+			return false;
+
 		m_rfLSFn = (lich4 >> 5) & 0x07U;
 		m_rfLSF.setFragment(lich, m_rfLSFn);
 
@@ -253,7 +257,7 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		unsigned char frame[M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES];
 		conv.decodeData(data + 2U + M17_SYNC_LENGTH_BYTES + M17_LICH_FRAGMENT_FEC_LENGTH_BYTES, frame);
 
-		bool valid = CM17CRC::checkCRC(frame, M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES);
+		bool valid = CM17CRC::checkCRC16(frame, M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES);
 		if (valid) {
 			m_rfFN = (frame[0U] << 8) + (frame[1U] << 0);
 		} else {
@@ -279,7 +283,7 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 			}
 
 			// Add the CRC
-			CM17CRC::encodeCRC(frame, M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES);
+			CM17CRC::encodeCRC16(frame, M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES);
 		}
 
 		unsigned char rfData[2U + M17_FRAME_LENGTH_BYTES];
@@ -293,12 +297,15 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		unsigned char lich[M17_LICH_FRAGMENT_LENGTH_BYTES];
 		m_rfLSF.getFragment(lich, m_rfLSFn);
 
+		// Add the fragment number
+		lich[5U] = (m_rfLSFn & 0x07U) << 5;
+
+		// Add the CRC
+		CM17CRC::encodeCRC8(lich, M17_LICH_FRAGMENT_LENGTH_BYTES);
+
 		unsigned int frag1, frag2, frag3, frag4;
 		CM17Utils::splitFragmentLICH(lich, frag1, frag2, frag3, frag4);
 
-		// Add the fragment number
-		frag4 |= (m_rfLSFn & 0x07U) << 5;
-
 		// Add Golay to the LICH fragment here
 		unsigned int lich1 = CGolay24128::encode24128(frag1);
 		unsigned int lich2 = CGolay24128::encode24128(frag2);
@@ -362,11 +369,9 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 				LogMessage("M17, received RF end of transmission from %s to %s, %.1f seconds, BER: %.1f%%", source.c_str(), dest.c_str(), float(m_rfFrames) / 25.0F, float(m_rfErrs * 100U) / float(m_rfBits));
 			writeEndRF();
 		}
-
-		return true;
 	}
 
-	return false;
+	return true;
 }
 
 unsigned int CM17Control::readModem(unsigned char* data)
@@ -511,15 +516,18 @@ void CM17Control::writeNetwork()
 		m_netFrames++;
 
 		// Add the fragment LICH
-		unsigned char lich[M17_LSF_FRAGMENT_LENGTH_BYTES];
+		unsigned char lich[M17_LICH_FRAGMENT_LENGTH_BYTES];
 		m_netLSF.getFragment(lich, m_netLSFn);
 
+		// Add the fragment number
+		lich[5U] = (m_netLSFn & 0x07U) << 5;
+
+		// Add the CRC
+		CM17CRC::encodeCRC8(lich, M17_LICH_FRAGMENT_LENGTH_BYTES);
+
 		unsigned int frag1, frag2, frag3, frag4;
 		CM17Utils::splitFragmentLICH(lich, frag1, frag2, frag3, frag4);
 
-		// Add the fragment number
-		frag4 |= (m_netLSFn & 0x07U) << 4;
-
 		// Add Golay to the LICH fragment here
 		unsigned int lich1 = CGolay24128::encode24128(frag1);
 		unsigned int lich2 = CGolay24128::encode24128(frag2);
@@ -533,7 +541,7 @@ void CM17Control::writeNetwork()
 		::memcpy(payload, netData + 28U, M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES);
 
 		// Add the CRC
-		CM17CRC::encodeCRC(payload, M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES);
+		CM17CRC::encodeCRC16(payload, M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES);
 
 		// Add the Convolution FEC
 		CM17Convolution conv;
diff --git a/M17LSF.cpp b/M17LSF.cpp
index 4d48f40..6caa1c4 100644
--- a/M17LSF.cpp
+++ b/M17LSF.cpp
@@ -162,7 +162,7 @@ void CM17LSF::getLinkSetup(unsigned char* data) const
 
 	::memcpy(data, m_lsf, M17_LSF_LENGTH_BYTES);
 
-	CM17CRC::encodeCRC(data, M17_LSF_LENGTH_BYTES);
+	CM17CRC::encodeCRC16(data, M17_LSF_LENGTH_BYTES);
 }
 
 void CM17LSF::setLinkSetup(const unsigned char* data)
@@ -171,14 +171,14 @@ void CM17LSF::setLinkSetup(const unsigned char* data)
 
 	::memcpy(m_lsf, data, M17_LSF_LENGTH_BYTES);
 
-	m_valid = CM17CRC::checkCRC(m_lsf, M17_LSF_LENGTH_BYTES);
+	m_valid = CM17CRC::checkCRC16(m_lsf, M17_LSF_LENGTH_BYTES);
 }
 
 void CM17LSF::getFragment(unsigned char* data, unsigned int n) const
 {
 	assert(data != NULL);
 
-	CM17CRC::encodeCRC(m_lsf, M17_LSF_LENGTH_BYTES);
+	CM17CRC::encodeCRC16(m_lsf, M17_LSF_LENGTH_BYTES);
 
 	::memcpy(data, m_lsf + (n * M17_LSF_FRAGMENT_LENGTH_BYTES), M17_LSF_FRAGMENT_LENGTH_BYTES);
 }
@@ -189,5 +189,5 @@ void CM17LSF::setFragment(const unsigned char* data, unsigned int n)
 
 	::memcpy(m_lsf + (n * M17_LSF_FRAGMENT_LENGTH_BYTES), data, M17_LSF_FRAGMENT_LENGTH_BYTES);
 
-	m_valid = CM17CRC::checkCRC(m_lsf, M17_LSF_LENGTH_BYTES);
+	m_valid = CM17CRC::checkCRC16(m_lsf, M17_LSF_LENGTH_BYTES);
 }

From 8efd77132f6c77f5484ee70e4f63f5bde3fea716 Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Fri, 26 Mar 2021 22:45:33 +0000
Subject: [PATCH 16/23] Rename the CRC4 functions correctly.

---
 M17CRC.cpp     | 10 +++++-----
 M17CRC.h       |  6 +++---
 M17Control.cpp |  6 +++---
 3 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/M17CRC.cpp b/M17CRC.cpp
index 695511e..1fd42f0 100644
--- a/M17CRC.cpp
+++ b/M17CRC.cpp
@@ -101,7 +101,7 @@ uint16_t CM17CRC::createCRC16(const unsigned char* in, unsigned int nBytes)
 	return crc;
 }
 
-bool CM17CRC::checkCRC8(unsigned char* in, unsigned int nBytes)
+bool CM17CRC::checkCRC4(unsigned char* in, unsigned int nBytes)
 {
 	assert(in != NULL);
 	assert(nBytes > 1U);
@@ -111,7 +111,7 @@ bool CM17CRC::checkCRC8(unsigned char* in, unsigned int nBytes)
 	// Mask out the 4-bit CRC location
 	in[nBytes - 1U] &= 0xF0U;
 
-	uint8_t crc = createCRC8(in, nBytes);
+	uint8_t crc = createCRC4(in, nBytes);
 
 	// Restore the original CRC
 	in[nBytes - 1U] |= save;
@@ -119,19 +119,19 @@ bool CM17CRC::checkCRC8(unsigned char* in, unsigned int nBytes)
 	return save == crc;
 }
 
-void CM17CRC::encodeCRC8(unsigned char* in, unsigned int nBytes)
+void CM17CRC::encodeCRC4(unsigned char* in, unsigned int nBytes)
 {
 	assert(in != NULL);
 	assert(nBytes > 1U);
 
 	in[nBytes - 1U] &= 0xF0U;
 
-	uint8_t crc = createCRC8(in, nBytes);
+	uint8_t crc = createCRC4(in, nBytes);
 
 	in[nBytes - 1U] |= crc & 0x0FU;
 }
 
-uint8_t CM17CRC::createCRC8(const unsigned char* in, unsigned int nBytes)
+uint8_t CM17CRC::createCRC4(const unsigned char* in, unsigned int nBytes)
 {
 	assert(in != NULL);
 
diff --git a/M17CRC.h b/M17CRC.h
index 5bc33bb..a1cfa53 100644
--- a/M17CRC.h
+++ b/M17CRC.h
@@ -27,12 +27,12 @@ public:
 	static bool checkCRC16(const unsigned char* in, unsigned int nBytes);
 	static void encodeCRC16(unsigned char* in, unsigned int nBytes);
 
-	static bool checkCRC8(unsigned char* in, unsigned int nBytes);
-	static void encodeCRC8(unsigned char* in, unsigned int nBytes);
+	static bool checkCRC4(unsigned char* in, unsigned int nBytes);
+	static void encodeCRC4(unsigned char* in, unsigned int nBytes);
 
 private:
 	static uint16_t createCRC16(const unsigned char* in, unsigned int nBytes);
-	static uint8_t  createCRC8(const unsigned char* in, unsigned int nBytes);
+	static uint8_t  createCRC4(const unsigned char* in, unsigned int nBytes);
 };
 
 #endif
diff --git a/M17Control.cpp b/M17Control.cpp
index 10238ce..070ccfd 100644
--- a/M17Control.cpp
+++ b/M17Control.cpp
@@ -217,7 +217,7 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		unsigned char lich[M17_LICH_FRAGMENT_LENGTH_BYTES];
 		CM17Utils::combineFragmentLICH(lich1, lich2, lich3, lich4, lich);
 
-		if (!CM17CRC::checkCRC8(lich, M17_LICH_FRAGMENT_LENGTH_BYTES))
+		if (!CM17CRC::checkCRC4(lich, M17_LICH_FRAGMENT_LENGTH_BYTES))
 			return false;
 
 		m_rfLSFn = (lich4 >> 5) & 0x07U;
@@ -301,7 +301,7 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		lich[5U] = (m_rfLSFn & 0x07U) << 5;
 
 		// Add the CRC
-		CM17CRC::encodeCRC8(lich, M17_LICH_FRAGMENT_LENGTH_BYTES);
+		CM17CRC::encodeCRC4(lich, M17_LICH_FRAGMENT_LENGTH_BYTES);
 
 		unsigned int frag1, frag2, frag3, frag4;
 		CM17Utils::splitFragmentLICH(lich, frag1, frag2, frag3, frag4);
@@ -523,7 +523,7 @@ void CM17Control::writeNetwork()
 		lich[5U] = (m_netLSFn & 0x07U) << 5;
 
 		// Add the CRC
-		CM17CRC::encodeCRC8(lich, M17_LICH_FRAGMENT_LENGTH_BYTES);
+		CM17CRC::encodeCRC4(lich, M17_LICH_FRAGMENT_LENGTH_BYTES);
 
 		unsigned int frag1, frag2, frag3, frag4;
 		CM17Utils::splitFragmentLICH(lich, frag1, frag2, frag3, frag4);

From 4422444179ec9ccb64e040263361114eafc27a67 Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Sat, 27 Mar 2021 14:51:53 +0000
Subject: [PATCH 17/23] Disable the LICH CRC and clean up the payload checksum
 handling.

---
 M17Control.cpp | 55 ++++++++++++++++++--------------------------------
 Version.h      |  2 +-
 2 files changed, 21 insertions(+), 36 deletions(-)

diff --git a/M17Control.cpp b/M17Control.cpp
index 070ccfd..14d1c83 100644
--- a/M17Control.cpp
+++ b/M17Control.cpp
@@ -217,8 +217,8 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		unsigned char lich[M17_LICH_FRAGMENT_LENGTH_BYTES];
 		CM17Utils::combineFragmentLICH(lich1, lich2, lich3, lich4, lich);
 
-		if (!CM17CRC::checkCRC4(lich, M17_LICH_FRAGMENT_LENGTH_BYTES))
-			return false;
+		// if (!CM17CRC::checkCRC4(lich, M17_LICH_FRAGMENT_LENGTH_BYTES))
+		//	return false;
 
 		m_rfLSFn = (lich4 >> 5) & 0x07U;
 		m_rfLSF.setFragment(lich, m_rfLSFn);
@@ -249,7 +249,7 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		}
 	}
 
-	if ((m_rfState == RS_RF_AUDIO || m_rfState == RS_RF_DATA) && data[0U] == TAG_DATA) {
+	if (m_rfState == RS_RF_AUDIO && data[0U] == TAG_DATA) {
 #if defined(DUMP_M17)
 		writeFile(data + 2U);
 #endif
@@ -261,28 +261,13 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		if (valid) {
 			m_rfFN = (frame[0U] << 8) + (frame[1U] << 0);
 		} else {
-			// Create a silence frame
 			m_rfFN++;
 
 			// The new FN
 			frame[0U] = m_rfFN >> 8;
 			frame[1U] = m_rfFN >> 0;
 
-			// Add silent audio
-			unsigned char dataType = m_rfLSF.getDataType();
-			switch (dataType) {
-			case M17_DATA_TYPE_VOICE:
-				::memcpy(frame + M17_FN_LENGTH_BYTES + 0U, M17_3200_SILENCE, 8U);
-				::memcpy(frame + M17_FN_LENGTH_BYTES + 8U, M17_3200_SILENCE, 8U);
-				break;
-			case M17_DATA_TYPE_VOICE_DATA:
-				::memcpy(frame + M17_FN_LENGTH_BYTES + 0U, M17_1600_SILENCE, 8U);
-				break;
-			default:
-				break;
-			}
-
-			// Add the CRC
+			// Recalculate the CRC
 			CM17CRC::encodeCRC16(frame, M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES + M17_CRC_LENGTH_BYTES);
 		}
 
@@ -301,7 +286,7 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		lich[5U] = (m_rfLSFn & 0x07U) << 5;
 
 		// Add the CRC
-		CM17CRC::encodeCRC4(lich, M17_LICH_FRAGMENT_LENGTH_BYTES);
+		// CM17CRC::encodeCRC4(lich, M17_LICH_FRAGMENT_LENGTH_BYTES);
 
 		unsigned int frag1, frag2, frag3, frag4;
 		CM17Utils::splitFragmentLICH(lich, frag1, frag2, frag3, frag4);
@@ -318,20 +303,20 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		conv.encodeData(frame, rfData + 2U + M17_SYNC_LENGTH_BYTES + M17_LICH_FRAGMENT_FEC_LENGTH_BYTES);
 
 		// Calculate the BER
-		if (valid) {
-			unsigned int errors = 0U;
-			for (unsigned int i = 2U; i < (M17_FRAME_LENGTH_BYTES + 2U); i++)
-				errors += countBits(rfData[i] ^ data[i]);
-
-			LogDebug("M17, FN: %u, errs: %u/384 (%.1f%%)", m_rfFN & 0x7FU, errors, float(errors) / 3.84F);
-
-			m_rfBits += M17_FRAME_LENGTH_BITS;
-			m_rfErrs += errors;
-
-			float ber = float(m_rfErrs) / float(m_rfBits);
-			m_display->writeM17BER(ber);
+		unsigned int errors = 0U;
+		for (unsigned int i = 0U; i < (M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES); i++) {
+			unsigned int offset = i + 2U + M17_SYNC_LENGTH_BYTES + M17_LICH_FRAGMENT_FEC_LENGTH_BYTES;
+			errors += countBits(rfData[offset] ^ data[offset]);
 		}
 
+		LogDebug("M17, FN: %u, errs: %u/144 (%.1f%%)", m_rfFN & 0x7FU, errors, float(errors) / 1.44F);
+
+		m_rfBits += M17_FN_LENGTH_BITS + M17_PAYLOAD_LENGTH_BITS;
+		m_rfErrs += errors;
+
+		float ber = float(m_rfErrs) / float(m_rfBits);
+		m_display->writeM17BER(ber);
+
 		unsigned char temp[M17_FRAME_LENGTH_BYTES];
 		interleaver(rfData + 2U, temp);
 		decorrelator(temp, rfData + 2U);
@@ -358,8 +343,8 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		if (m_rfLSFn >= 6U)
 			m_rfLSFn = 0U;
 
-		// EOT?
-		if ((m_rfFN & 0x8000U) == 0x8000U) {
+		// Only check for the EOT marker if the frame has a valid CRC
+		if (valid && (m_rfFN & 0x8000U) == 0x8000U) {
 			std::string source = m_rfLSF.getSource();
 			std::string dest   = m_rfLSF.getDest();
 
@@ -523,7 +508,7 @@ void CM17Control::writeNetwork()
 		lich[5U] = (m_netLSFn & 0x07U) << 5;
 
 		// Add the CRC
-		CM17CRC::encodeCRC4(lich, M17_LICH_FRAGMENT_LENGTH_BYTES);
+		// CM17CRC::encodeCRC4(lich, M17_LICH_FRAGMENT_LENGTH_BYTES);
 
 		unsigned int frag1, frag2, frag3, frag4;
 		CM17Utils::splitFragmentLICH(lich, frag1, frag2, frag3, frag4);
diff --git a/Version.h b/Version.h
index 564260a..19fef83 100644
--- a/Version.h
+++ b/Version.h
@@ -19,6 +19,6 @@
 #if !defined(VERSION_H)
 #define	VERSION_H
 
-const char* VERSION = "20210326";
+const char* VERSION = "20210327";
 
 #endif

From 6ac672e10619f4abe0e113ceaebcea00cbb62f11 Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Sat, 27 Mar 2021 20:00:53 +0000
Subject: [PATCH 18/23] Finally process the Golay(24,12,8) parity bit.

---
 AMBEFEC.cpp    | 37 +++++++++++++------------------------
 Golay24128.cpp | 24 ++++++++++++++----------
 Golay24128.h   |  6 +++---
 M17Control.cpp | 29 ++++++++---------------------
 M17Control.h   |  2 --
 Utils.cpp      | 14 +++++++++++++-
 Utils.h        |  4 +++-
 YSFFICH.cpp    | 14 +++++++++-----
 8 files changed, 63 insertions(+), 67 deletions(-)

diff --git a/AMBEFEC.cpp b/AMBEFEC.cpp
index 864c35d..4b28046 100644
--- a/AMBEFEC.cpp
+++ b/AMBEFEC.cpp
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2010,2014,2016,2018 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2010,2014,2016,2018,2021 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016 Mathias Weyland, HB9FRV
  *
  *   This program is free software; you can redistribute it and/or modify
@@ -20,6 +20,7 @@
 #include "Golay24128.h"
 #include "Hamming.h"
 #include "AMBEFEC.h"
+#include "Utils.h"
 
 #include <cstdio>
 #include <cassert>
@@ -792,10 +793,12 @@ unsigned int CAMBEFEC::regenerateIMBE(unsigned char* bytes) const
 
 unsigned int CAMBEFEC::regenerateDStar(unsigned int& a, unsigned int& b) const
 {
+	bool valid;
+
 	unsigned int orig_a = a;
 	unsigned int orig_b = b;
 
-	unsigned int data = CGolay24128::decode24128(a);
+	unsigned int data = CGolay24128::decode24128(a, valid);
 
 	a = CGolay24128::encode24128(data);
 
@@ -804,35 +807,29 @@ unsigned int CAMBEFEC::regenerateDStar(unsigned int& a, unsigned int& b) const
 
 	b ^= p;
 
-	unsigned int datb = CGolay24128::decode24128(b);
+	unsigned int datb = CGolay24128::decode24128(b, valid);
 
 	b = CGolay24128::encode24128(datb);
 
 	b ^= p;
 
-	unsigned int errsA = 0U, errsB = 0U;
-
 	unsigned int v = a ^ orig_a;
-	while (v != 0U) {
-		v &= v - 1U;
-		errsA++;
-	}
+	unsigned int errsA = CUtils::countBits(v);
 
 	v = b ^ orig_b;
-	while (v != 0U) {
-		v &= v - 1U;
-		errsB++;
-	}
+	unsigned int errsB = CUtils::countBits(v);
 
 	return errsA + errsB;
 }
 
 unsigned int CAMBEFEC::regenerateDMR(unsigned int& a, unsigned int& b, unsigned int& c) const
 {
+	bool valid;
+
 	unsigned int orig_a = a;
 	unsigned int orig_b = b;
 
-	unsigned int data = CGolay24128::decode24128(a);
+	unsigned int data = CGolay24128::decode24128(a, valid);
 
 	a = CGolay24128::encode24128(data);
 
@@ -847,19 +844,11 @@ unsigned int CAMBEFEC::regenerateDMR(unsigned int& a, unsigned int& b, unsigned
 
 	b ^= p;
 
-	unsigned int errsA = 0U, errsB = 0U;
-
 	unsigned int v = a ^ orig_a;
-	while (v != 0U) {
-		v &= v - 1U;
-		errsA++;
-	}
+	unsigned int errsA = CUtils::countBits(v);
 
 	v = b ^ orig_b;
-	while (v != 0U) {
-		v &= v - 1U;
-		errsB++;
-	}
+	unsigned int errsB = CUtils::countBits(v);
 
 	if (errsA >= 4U || ((errsA + errsB) >= 6U && errsA >= 2U)) {
 		a = 0xF00292U;
diff --git a/Golay24128.cpp b/Golay24128.cpp
index 417da00..715c8dc 100644
--- a/Golay24128.cpp
+++ b/Golay24128.cpp
@@ -1,9 +1,10 @@
 /*
- *   Copyright (C) 2010,2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2010,2016,2021 by Jonathan Naylor G4KLX
  *   Copyright (C) 2002 by Robert H. Morelos-Zaragoza. All rights reserved.
  */
 
 #include "Golay24128.h"
+#include "Utils.h"
 
 #include <cstdio>
 #include <cassert>
@@ -1089,20 +1090,23 @@ unsigned int CGolay24128::decode23127(unsigned int code)
 	return code >> 11;
 }
 
-unsigned int CGolay24128::decode24128(unsigned int code)
+unsigned int CGolay24128::decode24128(unsigned int input, bool& valid)
 {
-	return decode23127(code >> 1);
+	unsigned int syndrome = ::get_syndrome_23127(input >> 1);
+	unsigned int error_pattern = DECODING_TABLE_23127[syndrome] << 1;
+
+	unsigned int output = input ^ error_pattern;
+
+	valid = (CUtils::countBits(syndrome) < 3U) || !(CUtils::countBits(output) & 1);
+
+	return output >> 12;
 }
 
-unsigned int CGolay24128::decode24128(unsigned char* bytes)
+unsigned int CGolay24128::decode24128(unsigned char* bytes, bool& valid)
 {
 	assert(bytes != NULL);
 
-	unsigned int code = bytes[0U];
-	code <<= 8;
-	code |= bytes[1U];
-	code <<= 8;
-	code |= bytes[2U];
+	unsigned int code = (bytes[0U] << 16) | (bytes[1U] << 8) | (bytes[2U] << 0);
 
-	return decode23127(code >> 1);
+	return decode24128(code, valid);
 }
diff --git a/Golay24128.h b/Golay24128.h
index 1ac7852..721dcbc 100644
--- a/Golay24128.h
+++ b/Golay24128.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2010,2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2010,2016,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -25,8 +25,8 @@ public:
 	static unsigned int encode24128(unsigned int data);
 
 	static unsigned int decode23127(unsigned int code);
-	static unsigned int decode24128(unsigned int code);
-	static unsigned int decode24128(unsigned char* bytes);
+	static unsigned int decode24128(unsigned int code, bool& valid);
+	static unsigned int decode24128(unsigned char* bytes, bool& valid);
 };
 
 #endif
diff --git a/M17Control.cpp b/M17Control.cpp
index 14d1c83..4defcd7 100644
--- a/M17Control.cpp
+++ b/M17Control.cpp
@@ -206,13 +206,14 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 	}
 
 	if (m_rfState == RS_RF_LATE_ENTRY && data[0U] == TAG_DATA) {
-		unsigned int frag1, frag2, frag3, frag4;
-		CM17Utils::splitFragmentLICHFEC(data + 2U + M17_SYNC_LENGTH_BYTES, frag1, frag2, frag3, frag4);
+		bool valid1, valid2, valid3, valid4;
+		unsigned int lich1 = CGolay24128::decode24128(data + 2U + M17_SYNC_LENGTH_BYTES + 0U, valid1);
+		unsigned int lich2 = CGolay24128::decode24128(data + 2U + M17_SYNC_LENGTH_BYTES + 3U, valid2);
+		unsigned int lich3 = CGolay24128::decode24128(data + 2U + M17_SYNC_LENGTH_BYTES + 6U, valid3);
+		unsigned int lich4 = CGolay24128::decode24128(data + 2U + M17_SYNC_LENGTH_BYTES + 9U, valid4);
 
-		unsigned int lich1 = CGolay24128::decode24128(frag1);
-		unsigned int lich2 = CGolay24128::decode24128(frag2);
-		unsigned int lich3 = CGolay24128::decode24128(frag3);
-		unsigned int lich4 = CGolay24128::decode24128(frag4);
+		if (!valid1 || !valid2 || !valid3 || !valid4)
+			return false;
 
 		unsigned char lich[M17_LICH_FRAGMENT_LENGTH_BYTES];
 		CM17Utils::combineFragmentLICH(lich1, lich2, lich3, lich4, lich);
@@ -306,7 +307,7 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		unsigned int errors = 0U;
 		for (unsigned int i = 0U; i < (M17_FN_LENGTH_BYTES + M17_PAYLOAD_LENGTH_BYTES); i++) {
 			unsigned int offset = i + 2U + M17_SYNC_LENGTH_BYTES + M17_LICH_FRAGMENT_FEC_LENGTH_BYTES;
-			errors += countBits(rfData[offset] ^ data[offset]);
+			errors += CUtils::countBits(rfData[offset] ^ data[offset]);
 		}
 
 		LogDebug("M17, FN: %u, errs: %u/144 (%.1f%%)", m_rfFN & 0x7FU, errors, float(errors) / 1.44F);
@@ -785,17 +786,3 @@ void CM17Control::enable(bool enabled)
 
 	m_enabled = enabled;
 }
-
-unsigned int CM17Control::countBits(unsigned char byte)
-{
-	unsigned int count = 0U;
-
-	const unsigned char* p = &byte;
-
-	for (unsigned int i = 0U; i < 8U; i++) {
-		if (READ_BIT(p, i) != 0U)
-			count++;
-	}
-
-	return count;
-}
diff --git a/M17Control.h b/M17Control.h
index 9ed515c..d351099 100644
--- a/M17Control.h
+++ b/M17Control.h
@@ -92,8 +92,6 @@ private:
 
 	bool checkCallsign(const std::string& source) const;
 
-	unsigned int countBits(unsigned char byte);
-
 	void writeEndRF();
 	void writeEndNet();
 
diff --git a/Utils.cpp b/Utils.cpp
index 49ded13..3ecdf60 100644
--- a/Utils.cpp
+++ b/Utils.cpp
@@ -1,5 +1,5 @@
 /*
- *	Copyright (C) 2009,2014,2015,2016 Jonathan Naylor, G4KLX
+ *	Copyright (C) 2009,2014,2015,2016,2021 Jonathan Naylor, G4KLX
  *
  *	This program is free software; you can redistribute it and/or modify
  *	it under the terms of the GNU General Public License as published by
@@ -144,3 +144,15 @@ void CUtils::bitsToByteLE(const bool* bits, unsigned char& byte)
 	byte |= bits[6U] ? 0x40U : 0x00U;
 	byte |= bits[7U] ? 0x80U : 0x00U;
 }
+
+unsigned int CUtils::countBits(unsigned int v)
+{
+	unsigned int count = 0U;
+
+	while (v != 0U) {
+		v &= v - 1U;
+		count++;
+	}
+
+	return count;
+}
diff --git a/Utils.h b/Utils.h
index ade28c0..1929aa0 100644
--- a/Utils.h
+++ b/Utils.h
@@ -1,5 +1,5 @@
 /*
- *	Copyright (C) 2009,2014,2015 by Jonathan Naylor, G4KLX
+ *	Copyright (C) 2009,2014,2015,2021 by Jonathan Naylor, G4KLX
  *
  *	This program is free software; you can redistribute it and/or modify
  *	it under the terms of the GNU General Public License as published by
@@ -30,6 +30,8 @@ public:
 	static void bitsToByteBE(const bool* bits, unsigned char& byte);
 	static void bitsToByteLE(const bool* bits, unsigned char& byte);
 
+	static unsigned int countBits(unsigned int v);
+
 private:
 };
 
diff --git a/YSFFICH.cpp b/YSFFICH.cpp
index 7227014..ce37a7f 100644
--- a/YSFFICH.cpp
+++ b/YSFFICH.cpp
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2016,2017,2019,2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016,2017,2019,2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -99,10 +99,14 @@ bool CYSFFICH::decode(const unsigned char* bytes)
 	unsigned char output[13U];
 	viterbi.chainback(output, 96U);
 
-	unsigned int b0 = CGolay24128::decode24128(output + 0U);
-	unsigned int b1 = CGolay24128::decode24128(output + 3U);
-	unsigned int b2 = CGolay24128::decode24128(output + 6U);
-	unsigned int b3 = CGolay24128::decode24128(output + 9U);
+	bool valid1, valid2, valid3, valid4;
+	unsigned int b0 = CGolay24128::decode24128(output + 0U, valid1);
+	unsigned int b1 = CGolay24128::decode24128(output + 3U, valid2);
+	unsigned int b2 = CGolay24128::decode24128(output + 6U, valid3);
+	unsigned int b3 = CGolay24128::decode24128(output + 9U, valid4);
+
+	if (!valid1 || !valid2 || !valid3 || !valid4)
+		return false;
 
 	m_fich[0U] = (b0 >> 4) & 0xFFU;
 	m_fich[1U] = ((b0 << 4) & 0xF0U) | ((b1 >> 8) & 0x0FU);

From 389bd3b928d63516120034ab98a4796869644c60 Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Sun, 28 Mar 2021 15:29:26 +0100
Subject: [PATCH 19/23] Remove the CRC4 processing.

---
 M17CRC.cpp     | 60 --------------------------------------------------
 M17CRC.h       |  4 ----
 M17Control.cpp |  9 --------
 Version.h      |  2 +-
 4 files changed, 1 insertion(+), 74 deletions(-)

diff --git a/M17CRC.cpp b/M17CRC.cpp
index 1fd42f0..e65b10c 100644
--- a/M17CRC.cpp
+++ b/M17CRC.cpp
@@ -46,24 +46,6 @@ const uint16_t CRC16_TABLE[] = {0x0000U, 0x5935U, 0xB26AU, 0xEB5FU, 0x3DE1U, 0x6
 			       0xAC02U, 0xF537U, 0x2389U, 0x7ABCU, 0x91E3U, 0xC8D6U, 0x65AAU, 0x3C9FU, 0xD7C0U, 0x8EF5U, 0x584BU,
 			       0x017EU, 0xEA21U, 0xB314U};
 
-const uint8_t CRC4_TABLE[] = {
-					0x0, 0x7, 0xe, 0x9, 0x5, 0x2, 0xb, 0xc, 0xa, 0xd, 0x4, 0x3, 0xf, 0x8, 0x1, 0x6,
-					0xd, 0xa, 0x3, 0x4, 0x8, 0xf, 0x6, 0x1, 0x7, 0x0, 0x9, 0xe, 0x2, 0x5, 0xc, 0xb,
-					0x3, 0x4, 0xd, 0xa, 0x6, 0x1, 0x8, 0xf, 0x9, 0xe, 0x7, 0x0, 0xc, 0xb, 0x2, 0x5,
-					0xe, 0x9, 0x0, 0x7, 0xb, 0xc, 0x5, 0x2, 0x4, 0x3, 0xa, 0xd, 0x1, 0x6, 0xf, 0x8,
-					0x6, 0x1, 0x8, 0xf, 0x3, 0x4, 0xd, 0xa, 0xc, 0xb, 0x2, 0x5, 0x9, 0xe, 0x7, 0x0,
-					0xb, 0xc, 0x5, 0x2, 0xe, 0x9, 0x0, 0x7, 0x1, 0x6, 0xf, 0x8, 0x4, 0x3, 0xa, 0xd,
-					0x5, 0x2, 0xb, 0xc, 0x0, 0x7, 0xe, 0x9, 0xf, 0x8, 0x1, 0x6, 0xa, 0xd, 0x4, 0x3,
-					0x8, 0xf, 0x6, 0x1, 0xd, 0xa, 0x3, 0x4, 0x2, 0x5, 0xc, 0xb, 0x7, 0x0, 0x9, 0xe,
-					0xc, 0xb, 0x2, 0x5, 0x9, 0xe, 0x7, 0x0, 0x6, 0x1, 0x8, 0xf, 0x3, 0x4, 0xd, 0xa,
-					0x1, 0x6, 0xf, 0x8, 0x4, 0x3, 0xa, 0xd, 0xb, 0xc, 0x5, 0x2, 0xe, 0x9, 0x0, 0x7,
-					0xf, 0x8, 0x1, 0x6, 0xa, 0xd, 0x4, 0x3, 0x5, 0x2, 0xb, 0xc, 0x0, 0x7, 0xe, 0x9,
-					0x2, 0x5, 0xc, 0xb, 0x7, 0x0, 0x9, 0xe, 0x8, 0xf, 0x6, 0x1, 0xd, 0xa, 0x3, 0x4,
-					0xa, 0xd, 0x4, 0x3, 0xf, 0x8, 0x1, 0x6, 0x0, 0x7, 0xe, 0x9, 0x5, 0x2, 0xb, 0xc,
-					0x7, 0x0, 0x9, 0xe, 0x2, 0x5, 0xc, 0xb, 0xd, 0xa, 0x3, 0x4, 0x8, 0xf, 0x6, 0x1,
-					0x9, 0xe, 0x7, 0x0, 0xc, 0xb, 0x2, 0x5, 0x3, 0x4, 0xd, 0xa, 0x6, 0x1, 0x8, 0xf,
-					0x4, 0x3, 0xa, 0xd, 0x1, 0x6, 0xf, 0x8, 0xe, 0x9, 0x0, 0x7, 0xb, 0xc, 0x5, 0x2};
-
 bool CM17CRC::checkCRC16(const unsigned char* in, unsigned int nBytes)
 {
 	assert(in != NULL);
@@ -100,45 +82,3 @@ uint16_t CM17CRC::createCRC16(const unsigned char* in, unsigned int nBytes)
 
 	return crc;
 }
-
-bool CM17CRC::checkCRC4(unsigned char* in, unsigned int nBytes)
-{
-	assert(in != NULL);
-	assert(nBytes > 1U);
-
-	uint8_t save = in[nBytes - 1U] & 0x0FU;
-
-	// Mask out the 4-bit CRC location
-	in[nBytes - 1U] &= 0xF0U;
-
-	uint8_t crc = createCRC4(in, nBytes);
-
-	// Restore the original CRC
-	in[nBytes - 1U] |= save;
-
-	return save == crc;
-}
-
-void CM17CRC::encodeCRC4(unsigned char* in, unsigned int nBytes)
-{
-	assert(in != NULL);
-	assert(nBytes > 1U);
-
-	in[nBytes - 1U] &= 0xF0U;
-
-	uint8_t crc = createCRC4(in, nBytes);
-
-	in[nBytes - 1U] |= crc & 0x0FU;
-}
-
-uint8_t CM17CRC::createCRC4(const unsigned char* in, unsigned int nBytes)
-{
-	assert(in != NULL);
-
-	uint8_t crc = 0x0FU;
-
-	for (unsigned int i = 0U; i < nBytes; i++)
-		crc = CRC4_TABLE[crc ^ in[i]];
-
-	return crc;
-}
diff --git a/M17CRC.h b/M17CRC.h
index a1cfa53..d06a9de 100644
--- a/M17CRC.h
+++ b/M17CRC.h
@@ -27,12 +27,8 @@ public:
 	static bool checkCRC16(const unsigned char* in, unsigned int nBytes);
 	static void encodeCRC16(unsigned char* in, unsigned int nBytes);
 
-	static bool checkCRC4(unsigned char* in, unsigned int nBytes);
-	static void encodeCRC4(unsigned char* in, unsigned int nBytes);
-
 private:
 	static uint16_t createCRC16(const unsigned char* in, unsigned int nBytes);
-	static uint8_t  createCRC4(const unsigned char* in, unsigned int nBytes);
 };
 
 #endif
diff --git a/M17Control.cpp b/M17Control.cpp
index 4defcd7..aaf2342 100644
--- a/M17Control.cpp
+++ b/M17Control.cpp
@@ -218,9 +218,6 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		unsigned char lich[M17_LICH_FRAGMENT_LENGTH_BYTES];
 		CM17Utils::combineFragmentLICH(lich1, lich2, lich3, lich4, lich);
 
-		// if (!CM17CRC::checkCRC4(lich, M17_LICH_FRAGMENT_LENGTH_BYTES))
-		//	return false;
-
 		m_rfLSFn = (lich4 >> 5) & 0x07U;
 		m_rfLSF.setFragment(lich, m_rfLSFn);
 
@@ -286,9 +283,6 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		// Add the fragment number
 		lich[5U] = (m_rfLSFn & 0x07U) << 5;
 
-		// Add the CRC
-		// CM17CRC::encodeCRC4(lich, M17_LICH_FRAGMENT_LENGTH_BYTES);
-
 		unsigned int frag1, frag2, frag3, frag4;
 		CM17Utils::splitFragmentLICH(lich, frag1, frag2, frag3, frag4);
 
@@ -508,9 +502,6 @@ void CM17Control::writeNetwork()
 		// Add the fragment number
 		lich[5U] = (m_netLSFn & 0x07U) << 5;
 
-		// Add the CRC
-		// CM17CRC::encodeCRC4(lich, M17_LICH_FRAGMENT_LENGTH_BYTES);
-
 		unsigned int frag1, frag2, frag3, frag4;
 		CM17Utils::splitFragmentLICH(lich, frag1, frag2, frag3, frag4);
 
diff --git a/Version.h b/Version.h
index 19fef83..36c3a74 100644
--- a/Version.h
+++ b/Version.h
@@ -19,6 +19,6 @@
 #if !defined(VERSION_H)
 #define	VERSION_H
 
-const char* VERSION = "20210327";
+const char* VERSION = "20210328";
 
 #endif

From 8dc54ed21f8ee4677acec9ce701f451af22dc58d Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Mon, 29 Mar 2021 19:36:55 +0100
Subject: [PATCH 20/23] Ignore M17 packet data, for now.

---
 DMRControl.cpp   |  2 +-
 DMRDefines.h     |  8 ++++----
 DMRSlot.cpp      | 36 ++++++++++++++++++------------------
 DStarControl.cpp |  8 ++++----
 DStarDefines.h   |  6 +++---
 DStarNetwork.cpp |  6 +++---
 Defines.h        |  7 ++++---
 FMControl.cpp    |  2 +-
 M17Control.cpp   | 20 +++++++++++++++-----
 Modem.cpp        | 48 ++++++++++++++++++++++++------------------------
 NXDNControl.cpp  | 20 ++++++++++----------
 P25Control.cpp   | 16 ++++++++--------
 Version.h        |  2 +-
 YSFControl.cpp   | 20 ++++++++++----------
 14 files changed, 106 insertions(+), 95 deletions(-)

diff --git a/DMRControl.cpp b/DMRControl.cpp
index 5761080..40178ba 100644
--- a/DMRControl.cpp
+++ b/DMRControl.cpp
@@ -50,7 +50,7 @@ bool CDMRControl::processWakeup(const unsigned char* data)
 	assert(data != NULL);
 
 	// Wakeups always come in on slot 1
-	if (data[0U] != TAG_DATA || data[1U] != (DMR_IDLE_RX | DMR_SYNC_DATA | DT_CSBK))
+	if (data[0U] != TAG_DATA1 || data[1U] != (DMR_IDLE_RX | DMR_SYNC_DATA | DT_CSBK))
 		return false;
 
 	CDMRCSBK csbk;
diff --git a/DMRDefines.h b/DMRDefines.h
index 5b53c33..ca08c19 100644
--- a/DMRDefines.h
+++ b/DMRDefines.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -19,7 +19,7 @@
 #if !defined(DMRDefines_H)
 #define	DMRDefines_H
 
-#include "Defines.h"		// For TAG_DATA
+#include "Defines.h"		// For TAG_DATA1
 
 const unsigned int DMR_FRAME_LENGTH_BITS  = 264U;
 const unsigned int DMR_FRAME_LENGTH_BYTES = 33U;
@@ -54,13 +54,13 @@ const unsigned char DIRECT_SLOT2_DATA_SYNC[]  = {0x0DU, 0x75U, 0x57U, 0xF5U, 0xF
 const unsigned char SYNC_MASK[]               = {0x0FU, 0xFFU, 0xFFU, 0xFFU, 0xFFU, 0xFFU, 0xF0U};
 
 // The PR FILL and Data Sync pattern.
-const unsigned char DMR_IDLE_DATA[] = {TAG_DATA, 0x00U,
+const unsigned char DMR_IDLE_DATA[] = {TAG_DATA1, 0x00U,
 							0x53U, 0xC2U, 0x5EU, 0xABU, 0xA8U, 0x67U, 0x1DU, 0xC7U, 0x38U, 0x3BU, 0xD9U,
 							0x36U, 0x00U, 0x0DU, 0xFFU, 0x57U, 0xD7U, 0x5DU, 0xF5U, 0xD0U, 0x03U, 0xF6U,
 							0xE4U, 0x65U, 0x17U, 0x1BU, 0x48U, 0xCAU, 0x6DU, 0x4FU, 0xC6U, 0x10U, 0xB4U};
 
 // A silence frame only
-const unsigned char DMR_SILENCE_DATA[] = {TAG_DATA, 0x00U,
+const unsigned char DMR_SILENCE_DATA[] = {TAG_DATA1, 0x00U,
 							0xB9U, 0xE8U, 0x81U, 0x52U, 0x61U, 0x73U, 0x00U, 0x2AU, 0x6BU, 0xB9U, 0xE8U,
 							0x81U, 0x52U, 0x60U, 0x00U, 0x00U, 0x00U, 0x00U, 0x00U, 0x01U, 0x73U, 0x00U,
 							0x2AU, 0x6BU, 0xB9U, 0xE8U, 0x81U, 0x52U, 0x61U, 0x73U, 0x00U, 0x2AU, 0x6BU};
diff --git a/DMRSlot.cpp b/DMRSlot.cpp
index 1f405ca..374dc40 100644
--- a/DMRSlot.cpp
+++ b/DMRSlot.cpp
@@ -255,7 +255,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 			// Convert the Data Sync to be from the BS or MS as needed
 			CSync::addDMRDataSync(data + 2U, m_duplex);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			m_rfTimeoutTimer.start();
@@ -315,7 +315,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 			bptc.decode(data + 2U, payload);
 			bptc.encode(payload, data + 2U);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			if (m_duplex)
@@ -404,7 +404,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 			// Convert the Data Sync to be from the BS or MS as needed
 			CSync::addDMRDataSync(data + 2U, m_duplex);
 
-			data[0U] = m_rfFrames == 0U ? TAG_EOT : TAG_DATA;
+			data[0U] = m_rfFrames == 0U ? TAG_EOT : TAG_DATA1;
 			data[1U] = 0x00U;
 
 			if (m_duplex)
@@ -472,7 +472,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 			// Convert the Data Sync to be from the BS or MS as needed
 			CSync::addDMRDataSync(data + 2U, m_duplex);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			if (m_duplex)
@@ -545,7 +545,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 
 			m_rfFrames--;
 
-			data[0U] = m_rfFrames == 0U ? TAG_EOT : TAG_DATA;
+			data[0U] = m_rfFrames == 0U ? TAG_EOT : TAG_DATA1;
 			data[1U] = 0x00U;
 
 			if (m_duplex)
@@ -586,7 +586,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 			m_display->writeDMRRSSI(m_slotNo, m_rssi);
 
 			if (!m_rfTimeout) {
-				data[0U] = TAG_DATA;
+				data[0U] = TAG_DATA1;
 				data[1U] = 0x00U;
 
 				if (m_duplex)
@@ -752,7 +752,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 			emb.getData(data + 2U);
 
 			if (!m_rfTimeout) {
-				data[0U] = TAG_DATA;
+				data[0U] = TAG_DATA1;
 				data[1U] = 0x00U;
 
 				writeNetworkRF(data, DT_VOICE, errors);
@@ -828,7 +828,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 				slotType.setDataType(DT_VOICE_LC_HEADER);
 				slotType.getData(start + 2U);
 
-				start[0U] = TAG_DATA;
+				start[0U] = TAG_DATA1;
 				start[1U] = 0x00U;
 
 				m_rfTimeoutTimer.start();
@@ -880,7 +880,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 				m_rfBits += 141U;
 				m_rfFrames++;
 
-				data[0U] = TAG_DATA;
+				data[0U] = TAG_DATA1;
 				data[1U] = 0x00U;
 
 				if (m_duplex)
@@ -1088,7 +1088,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 		// Convert the Data Sync to be from the BS or MS as needed
 		CSync::addDMRDataSync(data + 2U, m_duplex);
 
-		data[0U] = TAG_DATA;
+		data[0U] = TAG_DATA1;
 		data[1U] = 0x00U;
 
 		m_lastFrameValid = false;
@@ -1177,7 +1177,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 			slotType.setDataType(DT_VOICE_LC_HEADER);
 			slotType.getData(start + 2U);
 
-			start[0U] = TAG_DATA;
+			start[0U] = TAG_DATA1;
 			start[1U] = 0x00U;
 
 			if (m_duplex) {
@@ -1224,7 +1224,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 		bptc.decode(data + 2U, payload);
 		bptc.encode(payload, data + 2U);
 
-		data[0U] = TAG_DATA;
+		data[0U] = TAG_DATA1;
 		data[1U] = 0x00U;
 
 		writeQueueNet(data);
@@ -1304,7 +1304,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 		// Convert the Data Sync to be from the BS or MS as needed
 		CSync::addDMRDataSync(data + 2U, m_duplex);
 
-		data[0U] = m_netFrames == 0U ? TAG_EOT : TAG_DATA;
+		data[0U] = m_netFrames == 0U ? TAG_EOT : TAG_DATA1;
 		data[1U] = 0x00U;
 
 		// Put a small delay into starting transmission
@@ -1374,7 +1374,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 			slotType.setDataType(DT_VOICE_LC_HEADER);
 			slotType.getData(start + 2U);
 
-			start[0U] = TAG_DATA;
+			start[0U] = TAG_DATA1;
 			start[1U] = 0x00U;
 
 			if (m_duplex) {
@@ -1417,7 +1417,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 				m_netErrs += m_fec.regenerateDMR(data + 2U);
 			m_netBits += 141U;
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			// Convert the Audio Sync to be from the BS or MS as needed
@@ -1572,7 +1572,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 		emb.setLCSS(lcss);
 		emb.getData(data + 2U);
 
-		data[0U] = TAG_DATA;
+		data[0U] = TAG_DATA1;
 		data[1U] = 0x00U;
 
 		// Initialise the lost packet data
@@ -1633,7 +1633,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 		// Convert the Data Sync to be from the BS or MS as needed
 		CSync::addDMRDataSync(data + 2U, m_duplex);
 
-		data[0U] = TAG_DATA;
+		data[0U] = TAG_DATA1;
 		data[1U] = 0x00U;
 
 		if (csbko == CSBKO_PRECCSBK && csbk.getDataContent()) {
@@ -1732,7 +1732,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 
 		m_netFrames--;
 
-		data[0U] = m_netFrames == 0U ? TAG_EOT : TAG_DATA;
+		data[0U] = m_netFrames == 0U ? TAG_EOT : TAG_DATA1;
 		data[1U] = 0x00U;
 
 #if defined(DUMP_DMR)
diff --git a/DStarControl.cpp b/DStarControl.cpp
index 786702a..61837db 100644
--- a/DStarControl.cpp
+++ b/DStarControl.cpp
@@ -1,5 +1,5 @@
 /*
- *	Copyright (C) 2015-2019 Jonathan Naylor, G4KLX
+ *	Copyright (C) 2015-2019,2021 Jonathan Naylor, G4KLX
  *
  *	This program is free software; you can redistribute it and/or modify
  *	it under the terms of the GNU General Public License as published by
@@ -429,7 +429,7 @@ bool CDStarControl::writeModem(unsigned char *data, unsigned int len)
 		}
 
 		return false;
-	} else if (type == TAG_DATA) {
+	} else if (type == TAG_DATA1) {
 		if (m_rfState == RS_RF_REJECTED) {
 			return false;
 		} else if (m_rfState == RS_RF_INVALID) {
@@ -779,13 +779,13 @@ void CDStarControl::writeNetwork()
 		LogMessage("D-Star, received network end of transmission from %8.8s/%4.4s to %8.8s, %.1f seconds, %u%% packet loss, BER: %.1f%%", my1, my2, your, float(m_netFrames) / 50.0F, (m_netLost * 100U) / m_netFrames, float(m_netErrs * 100U) / float(m_netBits));
 
 		writeEndNet();
-	} else if (type == TAG_DATA) {
+	} else if (type == TAG_DATA1) {
 		if (m_netState != RS_NET_AUDIO)
 			return;
 
 		unsigned char n = data[1U];
 
-		data[1U] = TAG_DATA;
+		data[1U] = TAG_DATA1;
 
 		unsigned int errors = 0U;
 		if (!m_netHeader.isDataPacket())
diff --git a/DStarDefines.h b/DStarDefines.h
index 2a3e90c..f6ad749 100644
--- a/DStarDefines.h
+++ b/DStarDefines.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2018,2019 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2018,2019,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -35,8 +35,8 @@ const unsigned char DSTAR_NULL_SLOW_SYNC_BYTES[] = { 0x55, 0x2D, 0x16 };
 // Note that these are already scrambled, 0x66 0x66 0x66 otherwise
 const unsigned char DSTAR_NULL_SLOW_DATA_BYTES[] = { 0x16, 0x29, 0xF5 };
 
-const unsigned char DSTAR_NULL_FRAME_SYNC_BYTES[] = { TAG_DATA, 0x9E, 0x8D, 0x32, 0x88, 0x26, 0x1A, 0x3F, 0x61, 0xE8, 0x55, 0x2D, 0x16 };
-const unsigned char DSTAR_NULL_FRAME_DATA_BYTES[] = { TAG_DATA, 0x9E, 0x8D, 0x32, 0x88, 0x26, 0x1A, 0x3F, 0x61, 0xE8, 0x16, 0x29, 0xF5 };
+const unsigned char DSTAR_NULL_FRAME_SYNC_BYTES[] = { TAG_DATA1, 0x9E, 0x8D, 0x32, 0x88, 0x26, 0x1A, 0x3F, 0x61, 0xE8, 0x55, 0x2D, 0x16 };
+const unsigned char DSTAR_NULL_FRAME_DATA_BYTES[] = { TAG_DATA1, 0x9E, 0x8D, 0x32, 0x88, 0x26, 0x1A, 0x3F, 0x61, 0xE8, 0x16, 0x29, 0xF5 };
 
 const unsigned int  DSTAR_VOICE_FRAME_LENGTH_BYTES = 9U;
 const unsigned int  DSTAR_DATA_FRAME_LENGTH_BYTES  = 3U;
diff --git a/DStarNetwork.cpp b/DStarNetwork.cpp
index 4a978e2..2de9051 100644
--- a/DStarNetwork.cpp
+++ b/DStarNetwork.cpp
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2014,2016,2019,2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2014,2016,2019,2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -263,7 +263,7 @@ void CDStarNetwork::clock(unsigned int ms)
 					m_inId = 0U;
 					ctrl[1U] = TAG_EOT;
 				} else {
-					ctrl[1U] = TAG_DATA;
+					ctrl[1U] = TAG_DATA1;
 				}
 
 				ctrl[2U] = buffer[7] & 0x3FU;
@@ -299,7 +299,7 @@ unsigned int CDStarNetwork::read(unsigned char* data, unsigned int length)
 
 	switch (buffer[0U]) {
 	case TAG_HEADER:
-	case TAG_DATA:
+	case TAG_DATA1:
 	case TAG_EOT:
 		::memcpy(data, buffer, c);
 		return c;
diff --git a/Defines.h b/Defines.h
index 0381a43..58f4348 100644
--- a/Defines.h
+++ b/Defines.h
@@ -36,9 +36,10 @@ const unsigned char MODE_ERROR   = 100U;
 const unsigned char MODE_QUIT    = 110U;
 
 const unsigned char TAG_HEADER = 0x00U;
-const unsigned char TAG_DATA   = 0x01U;
-const unsigned char TAG_LOST   = 0x02U;
-const unsigned char TAG_EOT    = 0x03U;
+const unsigned char TAG_DATA1  = 0x01U;
+const unsigned char TAG_DATA2  = 0x02U;
+const unsigned char TAG_LOST   = 0x03U;
+const unsigned char TAG_EOT    = 0x04U;
 
 const unsigned int  DSTAR_MODEM_DATA_LEN = 220U;
 
diff --git a/FMControl.cpp b/FMControl.cpp
index 7f1ff07..1708c61 100644
--- a/FMControl.cpp
+++ b/FMControl.cpp
@@ -81,7 +81,7 @@ bool CFMControl::writeModem(const unsigned char* data, unsigned int length)
     if (data[0U] == TAG_EOT)
         return m_network->writeEOT();
 
-    if (data[0U] != TAG_DATA)
+    if (data[0U] != TAG_DATA1)
         return false;
 
     m_incomingRFAudio.addData(data + 1U, length - 1U);
diff --git a/M17Control.cpp b/M17Control.cpp
index aaf2342..653413d 100644
--- a/M17Control.cpp
+++ b/M17Control.cpp
@@ -135,6 +135,12 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		return false;
 	}
 
+	// Ignore packet data
+	if (type == TAG_DATA2) {
+		m_rfState = RS_RF_LISTENING;
+		return false;
+	}
+
 	// Have we got RSSI bytes on the end?
 	if (len == (M17_FRAME_LENGTH_BYTES + 4U)) {
 		uint16_t raw = 0U;
@@ -200,12 +206,12 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		}
 	}
 
-	if (m_rfState == RS_RF_LISTENING && data[0U] == TAG_DATA) {
+	if (m_rfState == RS_RF_LISTENING && data[0U] == TAG_DATA1) {
 		m_rfState = RS_RF_LATE_ENTRY;
 		m_rfLSF.reset();
 	}
 
-	if (m_rfState == RS_RF_LATE_ENTRY && data[0U] == TAG_DATA) {
+	if (m_rfState == RS_RF_LATE_ENTRY && data[0U] == TAG_DATA1) {
 		bool valid1, valid2, valid3, valid4;
 		unsigned int lich1 = CGolay24128::decode24128(data + 2U + M17_SYNC_LENGTH_BYTES + 0U, valid1);
 		unsigned int lich2 = CGolay24128::decode24128(data + 2U + M17_SYNC_LENGTH_BYTES + 3U, valid2);
@@ -247,7 +253,7 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		}
 	}
 
-	if (m_rfState == RS_RF_AUDIO && data[0U] == TAG_DATA) {
+	if (m_rfState == RS_RF_AUDIO && data[0U] == TAG_DATA1) {
 #if defined(DUMP_M17)
 		writeFile(data + 2U);
 #endif
@@ -271,7 +277,7 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 
 		unsigned char rfData[2U + M17_FRAME_LENGTH_BYTES];
 
-		rfData[0U] = TAG_DATA;
+		rfData[0U] = TAG_DATA1;
 		rfData[1U] = 0x00U;
 
 		// Generate the sync
@@ -487,7 +493,7 @@ void CM17Control::writeNetwork()
 	if (m_netState == RS_NET_AUDIO) {
 		unsigned char data[M17_FRAME_LENGTH_BYTES + 2U];
 
-		data[0U] = TAG_DATA;
+		data[0U] = TAG_DATA1;
 		data[1U] = 0x00U;
 
 		// Generate the sync
@@ -547,6 +553,10 @@ void CM17Control::writeNetwork()
 
 bool CM17Control::processRFHeader(bool lateEntry)
 {
+	unsigned char packetStream = m_rfLSF.getPacketStream();
+	if (packetStream == M17_PACKET_TYPE)
+		return false;
+
 	unsigned char can = m_rfLSF.getCAN();
 	if (can != m_can)
 		return false;
diff --git a/Modem.cpp b/Modem.cpp
index 795302b..1a33935 100644
--- a/Modem.cpp
+++ b/Modem.cpp
@@ -468,7 +468,7 @@ void CModem::clock(unsigned int ms)
 					unsigned char data = m_length - m_offset + 1U;
 					m_rxDStarData.addData(&data, 1U);
 
-					data = TAG_DATA;
+					data = TAG_DATA1;
 					m_rxDStarData.addData(&data, 1U);
 
 					m_rxDStarData.addData(m_buffer + m_offset, m_length - m_offset);
@@ -509,7 +509,7 @@ void CModem::clock(unsigned int ms)
 					if (m_buffer[3U] == (DMR_SYNC_DATA | DT_TERMINATOR_WITH_LC))
 						data = TAG_EOT;
 					else
-						data = TAG_DATA;
+						data = TAG_DATA1;
 					m_rxDMRData1.addData(&data, 1U);
 
 					m_rxDMRData1.addData(m_buffer + m_offset, m_length - m_offset);
@@ -526,7 +526,7 @@ void CModem::clock(unsigned int ms)
 					if (m_buffer[3U] == (DMR_SYNC_DATA | DT_TERMINATOR_WITH_LC))
 						data = TAG_EOT;
 					else
-						data = TAG_DATA;
+						data = TAG_DATA1;
 					m_rxDMRData2.addData(&data, 1U);
 
 					m_rxDMRData2.addData(m_buffer + m_offset, m_length - m_offset);
@@ -564,7 +564,7 @@ void CModem::clock(unsigned int ms)
 					unsigned char data = m_length - m_offset + 1U;
 					m_rxYSFData.addData(&data, 1U);
 
-					data = TAG_DATA;
+					data = TAG_DATA1;
 					m_rxYSFData.addData(&data, 1U);
 
 					m_rxYSFData.addData(m_buffer + m_offset, m_length - m_offset);
@@ -604,7 +604,7 @@ void CModem::clock(unsigned int ms)
 				unsigned char data = m_length - m_offset + 1U;
 				m_rxP25Data.addData(&data, 1U);
 
-				data = TAG_DATA;
+				data = TAG_DATA1;
 				m_rxP25Data.addData(&data, 1U);
 
 				m_rxP25Data.addData(m_buffer + m_offset, m_length - m_offset);
@@ -630,7 +630,7 @@ void CModem::clock(unsigned int ms)
 				unsigned char data = m_length - m_offset + 1U;
 				m_rxNXDNData.addData(&data, 1U);
 
-				data = TAG_DATA;
+				data = TAG_DATA1;
 				m_rxNXDNData.addData(&data, 1U);
 
 				m_rxNXDNData.addData(m_buffer + m_offset, m_length - m_offset);
@@ -670,7 +670,7 @@ void CModem::clock(unsigned int ms)
 				unsigned char data = m_length - 2U;
 				m_rxM17Data.addData(&data, 1U);
 
-				data = TAG_DATA;
+				data = TAG_DATA1;
 				m_rxM17Data.addData(&data, 1U);
 
 				m_rxM17Data.addData(m_buffer + 3U, m_length - 3U);
@@ -684,7 +684,7 @@ void CModem::clock(unsigned int ms)
 				unsigned char data = m_length - 2U;
 				m_rxM17Data.addData(&data, 1U);
 
-				data = TAG_DATA;
+				data = TAG_DATA2;
 				m_rxM17Data.addData(&data, 1U);
 
 				m_rxM17Data.addData(m_buffer + 3U, m_length - 3U);
@@ -710,7 +710,7 @@ void CModem::clock(unsigned int ms)
 				unsigned int data1 = m_length - m_offset + 1U;
 				m_rxFMData.addData((unsigned char*)&data1, sizeof(unsigned int));
 
-				unsigned char data2 = TAG_DATA;
+				unsigned char data2 = TAG_DATA1;
 				m_rxFMData.addData(&data2, 1U);
 
 				m_rxFMData.addData(m_buffer + m_offset, m_length - m_offset);
@@ -1322,7 +1322,7 @@ bool CModem::writeDStarData(const unsigned char* data, unsigned int length)
 		case TAG_HEADER:
 			buffer[2U] = MMDVM_DSTAR_HEADER;
 			break;
-		case TAG_DATA:
+		case TAG_DATA1:
 			buffer[2U] = MMDVM_DSTAR_DATA;
 			break;
 		case TAG_EOT:
@@ -1361,7 +1361,7 @@ bool CModem::writeDMRData1(const unsigned char* data, unsigned int length)
 	assert(data != NULL);
 	assert(length > 0U);
 
-	if (data[0U] != TAG_DATA && data[0U] != TAG_EOT)
+	if (data[0U] != TAG_DATA1 && data[0U] != TAG_EOT)
 		return false;
 
 	unsigned char buffer[40U];
@@ -1384,7 +1384,7 @@ bool CModem::writeDMRData2(const unsigned char* data, unsigned int length)
 	assert(data != NULL);
 	assert(length > 0U);
 
-	if (data[0U] != TAG_DATA && data[0U] != TAG_EOT)
+	if (data[0U] != TAG_DATA1 && data[0U] != TAG_EOT)
 		return false;
 
 	unsigned char buffer[40U];
@@ -1414,7 +1414,7 @@ bool CModem::writeYSFData(const unsigned char* data, unsigned int length)
 	assert(data != NULL);
 	assert(length > 0U);
 
-	if (data[0U] != TAG_DATA && data[0U] != TAG_EOT)
+	if (data[0U] != TAG_DATA1 && data[0U] != TAG_EOT)
 		return false;
 
 	unsigned char buffer[130U];
@@ -1444,7 +1444,7 @@ bool CModem::writeP25Data(const unsigned char* data, unsigned int length)
 	assert(data != NULL);
 	assert(length > 0U);
 
-	if (data[0U] != TAG_HEADER && data[0U] != TAG_DATA && data[0U] != TAG_EOT)
+	if (data[0U] != TAG_HEADER && data[0U] != TAG_DATA1 && data[0U] != TAG_EOT)
 		return false;
 
 	unsigned char buffer[250U];
@@ -1474,7 +1474,7 @@ bool CModem::writeNXDNData(const unsigned char* data, unsigned int length)
 	assert(data != NULL);
 	assert(length > 0U);
 
-	if (data[0U] != TAG_DATA && data[0U] != TAG_EOT)
+	if (data[0U] != TAG_DATA1 && data[0U] != TAG_EOT)
 		return false;
 
 	unsigned char buffer[130U];
@@ -1504,7 +1504,7 @@ bool CModem::writeM17Data(const unsigned char* data, unsigned int length)
 	assert(data != NULL);
 	assert(length > 0U);
 
-	if (data[0U] != TAG_HEADER && data[0U] != TAG_DATA && data[0U] != TAG_EOT)
+	if (data[0U] != TAG_HEADER && data[0U] != TAG_DATA1 && data[0U] != TAG_EOT)
 		return false;
 
 	unsigned char buffer[130U];
@@ -1823,7 +1823,7 @@ bool CModem::writePOCSAGInfo(unsigned int ric, const std::string& message)
 	unsigned char buffer[250U];
 
 	buffer[0U] = MMDVM_FRAME_START;
-	buffer[1U] = length + 11U;
+	buffer[1U] = (unsigned char)length + 11U;
 	buffer[2U] = MMDVM_QSO_INFO;
 
 	buffer[3U] = MODE_POCSAG;
@@ -1832,7 +1832,7 @@ bool CModem::writePOCSAGInfo(unsigned int ric, const std::string& message)
 
 	::memcpy(buffer + 11U, message.c_str(), length);
 
-	int ret = m_port->write(buffer, length + 11U);
+	int ret = m_port->write(buffer, (unsigned int)length + 11U);
 
 	return ret != int(length + 11U);
 }
@@ -1846,14 +1846,14 @@ bool CModem::writeIPInfo(const std::string& address)
 	unsigned char buffer[25U];
 
 	buffer[0U] = MMDVM_FRAME_START;
-	buffer[1U] = length + 4U;
+	buffer[1U] = (unsigned char)length + 4U;
 	buffer[2U] = MMDVM_QSO_INFO;
 
 	buffer[3U] = 250U;
 
 	::memcpy(buffer + 4U, address.c_str(), length);
 
-	int ret = m_port->write(buffer, length + 4U);
+	int ret = m_port->write(buffer, (unsigned int)length + 4U);
 
 	return ret != int(length + 4U);
 }
@@ -2485,7 +2485,7 @@ bool CModem::sendCWId(const std::string& callsign)
 {
 	assert(m_port != NULL);
 
-	unsigned int length = callsign.length();
+	unsigned int length = (unsigned int)callsign.length();
 	if (length > 200U)
 		length = 200U;
 
@@ -2631,7 +2631,7 @@ bool CModem::setFMCallsignParams()
 	assert(m_port != NULL);
 
 	unsigned char buffer[80U];
-	unsigned char len = 10U + m_fmCallsign.size();
+	unsigned char len = 10U + (unsigned char)m_fmCallsign.size();
 
 	buffer[0U] = MMDVM_FRAME_START;
 	buffer[1U] = len;
@@ -2692,7 +2692,7 @@ bool CModem::setFMAckParams()
 	assert(m_port != NULL);
 
 	unsigned char buffer[80U];
-	unsigned char len = 8U + m_fmRfAck.size();
+	unsigned char len = 8U + (unsigned char)m_fmRfAck.size();
 
 	buffer[0U] = MMDVM_FRAME_START;
 	buffer[1U] = len;
@@ -2811,7 +2811,7 @@ bool CModem::setFMExtParams()
 	assert(m_port != NULL);
 
 	unsigned char buffer[80U];
-	unsigned char len = 7U + m_fmExtAck.size();
+	unsigned char len = 7U + (unsigned char)m_fmExtAck.size();
 
 	buffer[0U] = MMDVM_FRAME_START;
 	buffer[1U] = len;
diff --git a/NXDNControl.cpp b/NXDNControl.cpp
index 119fad6..d040ca7 100644
--- a/NXDNControl.cpp
+++ b/NXDNControl.cpp
@@ -1,5 +1,5 @@
 /*
- *	Copyright (C) 2015-2020 Jonathan Naylor, G4KLX
+ *	Copyright (C) 2015-2021 Jonathan Naylor, G4KLX
  *
  *	This program is free software; you can redistribute it and/or modify
  *	it under the terms of the GNU General Public License as published by
@@ -223,7 +223,7 @@ bool CNXDNControl::processVoice(unsigned char usc, unsigned char option, unsigne
 
 		m_rfLayer3 = layer3;
 
-		data[0U] = type == NXDN_MESSAGE_TYPE_TX_REL ? TAG_EOT : TAG_DATA;
+		data[0U] = type == NXDN_MESSAGE_TYPE_TX_REL ? TAG_EOT : TAG_DATA1;
 		data[1U] = 0x00U;
 
 		CSync::addNXDNSync(data + 2U);
@@ -401,7 +401,7 @@ bool CNXDNControl::processVoice(unsigned char usc, unsigned char option, unsigne
 			// Create a dummy start message
 			unsigned char start[NXDN_FRAME_LENGTH_BYTES + 2U];
 
-			start[0U] = TAG_DATA;
+			start[0U] = TAG_DATA1;
 			start[1U] = 0x00U;
 
 			// Generate the sync
@@ -539,7 +539,7 @@ bool CNXDNControl::processVoice(unsigned char usc, unsigned char option, unsigne
 			facch12.getRaw(netData + 5U + 14U);
 		}
 
-		data[0U] = TAG_DATA;
+		data[0U] = TAG_DATA1;
 		data[1U] = 0x00U;
 
 		scrambler(data + 2U);
@@ -638,12 +638,12 @@ bool CNXDNControl::processData(unsigned char option, unsigned char *data)
 
 	if (validUDCH) {
 		type = layer3.getMessageType();
-		data[0U] = type == NXDN_MESSAGE_TYPE_TX_REL ? TAG_EOT : TAG_DATA;
+		data[0U] = type == NXDN_MESSAGE_TYPE_TX_REL ? TAG_EOT : TAG_DATA1;
 
 		udch.setRAN(m_ran);
 		udch.encode(data + 2U);
 	} else {
-		data[0U] = TAG_DATA;
+		data[0U] = TAG_DATA1;
 		data[1U] = 0x00U;
 	}
 
@@ -785,7 +785,7 @@ void CNXDNControl::writeNetwork()
 		}
 
 		if (m_netState == RS_NET_DATA) {
-			data[0U] = type == NXDN_MESSAGE_TYPE_TX_REL ? TAG_EOT : TAG_DATA;
+			data[0U] = type == NXDN_MESSAGE_TYPE_TX_REL ? TAG_EOT : TAG_DATA1;
 			data[1U] = 0x00U;
 
 			CNXDNUDCH udch;
@@ -826,7 +826,7 @@ void CNXDNControl::writeNetwork()
 		facch.encode(data + 2U, NXDN_FSW_LENGTH_BITS + NXDN_LICH_LENGTH_BITS + NXDN_SACCH_LENGTH_BITS);
 		facch.encode(data + 2U, NXDN_FSW_LENGTH_BITS + NXDN_LICH_LENGTH_BITS + NXDN_SACCH_LENGTH_BITS + NXDN_FACCH1_LENGTH_BITS);
 
-		data[0U] = type == NXDN_MESSAGE_TYPE_TX_REL ? TAG_EOT : TAG_DATA;
+		data[0U] = type == NXDN_MESSAGE_TYPE_TX_REL ? TAG_EOT : TAG_DATA1;
 		data[1U] = 0x00U;
 
 		scrambler(data + 2U);
@@ -907,7 +907,7 @@ void CNXDNControl::writeNetwork()
 			// Create a dummy start message
 			unsigned char start[NXDN_FRAME_LENGTH_BYTES + 2U];
 
-			start[0U] = TAG_DATA;
+			start[0U] = TAG_DATA1;
 			start[1U] = 0x00U;
 
 			// Generate the sync
@@ -942,7 +942,7 @@ void CNXDNControl::writeNetwork()
 
 		m_netFrames++;
 
-		data[0U] = TAG_DATA;
+		data[0U] = TAG_DATA1;
 		data[1U] = 0x00U;
 
 		CNXDNSACCH sacch;
diff --git a/P25Control.cpp b/P25Control.cpp
index b9825f0..3e382ea 100644
--- a/P25Control.cpp
+++ b/P25Control.cpp
@@ -1,5 +1,5 @@
 /*
-*   Copyright (C) 2016-2019 by Jonathan Naylor G4KLX
+*   Copyright (C) 2016-2019,2021 by Jonathan Naylor G4KLX
 *   Copyright (C) 2018 by Bryan Biedenkapp <gatekeep@gmail.com>
 *
 *   This program is free software; you can redistribute it and/or modify
@@ -303,7 +303,7 @@ bool CP25Control::writeModem(unsigned char* data, unsigned int len)
 			::memcpy(m_rfLDU, data + 2U, P25_LDU_FRAME_LENGTH_BYTES);
 
 			if (m_duplex) {
-				data[0U] = TAG_DATA;
+				data[0U] = TAG_DATA1;
 				data[1U] = 0x00U;
 				writeQueueRF(data, P25_LDU_FRAME_LENGTH_BYTES + 2U);
 			}
@@ -349,7 +349,7 @@ bool CP25Control::writeModem(unsigned char* data, unsigned int len)
 			::memcpy(m_rfLDU, data + 2U, P25_LDU_FRAME_LENGTH_BYTES);
 
 			if (m_duplex) {
-				data[0U] = TAG_DATA;
+				data[0U] = TAG_DATA1;
 				data[1U] = 0x00U;
 				writeQueueRF(data, P25_LDU_FRAME_LENGTH_BYTES + 2U);
 			}
@@ -399,7 +399,7 @@ bool CP25Control::writeModem(unsigned char* data, unsigned int len)
 			setBusyBits(data + 2U, P25_SS0_START, true, true);
 
 			if (m_duplex) {
-				data[0U] = TAG_DATA;
+				data[0U] = TAG_DATA1;
 				data[1U] = 0x00U;
 
 				writeQueueRF(data, P25_TSDU_FRAME_LENGTH_BYTES + 2U);
@@ -425,7 +425,7 @@ bool CP25Control::writeModem(unsigned char* data, unsigned int len)
 			setBusyBits(data + 2U, P25_SS0_START, true, true);
 
 			if (m_duplex) {
-				data[0U] = TAG_DATA;
+				data[0U] = TAG_DATA1;
 				data[1U] = 0x00U;
 
 				writeQueueRF(data, P25_TSDU_FRAME_LENGTH_BYTES + 2U);
@@ -569,7 +569,7 @@ bool CP25Control::writeModem(unsigned char* data, unsigned int len)
 				addBusyBits(pdu + 2U, newBitLength, false, true);
 
 				if (m_duplex) {
-					pdu[0U] = TAG_DATA;
+					pdu[0U] = TAG_DATA1;
 					pdu[1U] = 0x00U;
 					writeQueueRF(pdu, newByteLength + 2U);
 				}
@@ -1010,7 +1010,7 @@ void CP25Control::createNetLDU1()
 	unsigned char buffer[P25_LDU_FRAME_LENGTH_BYTES + 2U];
 	::memset(buffer, 0x00U, P25_LDU_FRAME_LENGTH_BYTES + 2U);
 
-	buffer[0U] = TAG_DATA;
+	buffer[0U] = TAG_DATA1;
 	buffer[1U] = 0x00U;
 
 	// Add the sync
@@ -1058,7 +1058,7 @@ void CP25Control::createNetLDU2()
 	unsigned char buffer[P25_LDU_FRAME_LENGTH_BYTES + 2U];
 	::memset(buffer, 0x00U, P25_LDU_FRAME_LENGTH_BYTES + 2U);
 
-	buffer[0U] = TAG_DATA;
+	buffer[0U] = TAG_DATA1;
 	buffer[1U] = 0x00U;
 
 	// Add the sync
diff --git a/Version.h b/Version.h
index 36c3a74..7dbf25d 100644
--- a/Version.h
+++ b/Version.h
@@ -19,6 +19,6 @@
 #if !defined(VERSION_H)
 #define	VERSION_H
 
-const char* VERSION = "20210328";
+const char* VERSION = "20210329";
 
 #endif
diff --git a/YSFControl.cpp b/YSFControl.cpp
index 8855160..efb2213 100644
--- a/YSFControl.cpp
+++ b/YSFControl.cpp
@@ -1,5 +1,5 @@
 /*
- *	Copyright (C) 2015-2020 Jonathan Naylor, G4KLX
+ *	Copyright (C) 2015-2021 Jonathan Naylor, G4KLX
  *
  *	This program is free software; you can redistribute it and/or modify
  *	it under the terms of the GNU General Public License as published by
@@ -265,7 +265,7 @@ bool CYSFControl::processVWData(bool valid, unsigned char *data)
 
 			fich.encode(data + 2U);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			writeNetwork(data, m_rfFrames % 128U);
@@ -358,7 +358,7 @@ bool CYSFControl::processVWData(bool valid, unsigned char *data)
 
 			fich.encode(data + 2U);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			writeNetwork(data, m_rfFrames % 128U);
@@ -434,7 +434,7 @@ bool CYSFControl::processDNData(bool valid, unsigned char *data)
 
 			fich.encode(data + 2U);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			writeNetwork(data, m_rfFrames % 128U);
@@ -540,7 +540,7 @@ bool CYSFControl::processDNData(bool valid, unsigned char *data)
 
 			fich.encode(data + 2U);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			writeNetwork(data, m_rfFrames % 128U);
@@ -636,7 +636,7 @@ bool CYSFControl::processDNData(bool valid, unsigned char *data)
 			CYSFPayload payload;
 			payload.writeHeader(buffer + 2U, csd1, csd2);
 
-			buffer[0U] = TAG_DATA;
+			buffer[0U] = TAG_DATA1;
 			buffer[1U] = 0x00U;
 
 			writeNetwork(buffer, m_rfFrames % 128U);
@@ -660,7 +660,7 @@ bool CYSFControl::processDNData(bool valid, unsigned char *data)
 
 			fich.encode(data + 2U);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			writeNetwork(data, m_rfFrames % 128U);
@@ -733,7 +733,7 @@ bool CYSFControl::processFRData(bool valid, unsigned char *data)
 
 			fich.encode(data + 2U);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			writeNetwork(data, m_rfFrames % 128U);
@@ -814,7 +814,7 @@ bool CYSFControl::processFRData(bool valid, unsigned char *data)
 
 			fich.encode(data + 2U);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			writeNetwork(data, m_rfFrames % 128U);
@@ -949,7 +949,7 @@ void CYSFControl::writeNetwork()
 			return;
 	}
 
-	data[33U] = end ? TAG_EOT : TAG_DATA;
+	data[33U] = end ? TAG_EOT : TAG_DATA1;
 	data[34U] = 0x00U;
 
 	if (valid) {

From c08b41a17a641e9fc6e7e71642c3580a1ed37341 Mon Sep 17 00:00:00 2001
From: Daniel Caujolle-Bert <f1rmb.daniel@naboo-homelinux.org>
Date: Wed, 31 Mar 2021 13:34:31 +0200
Subject: [PATCH 21/23] Fix nasty bug in UDPSocket::close().

---
 UDPSocket.cpp | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/UDPSocket.cpp b/UDPSocket.cpp
index ad8a0eb..7b819fe 100644
--- a/UDPSocket.cpp
+++ b/UDPSocket.cpp
@@ -188,6 +188,8 @@ bool CUDPSocket::open(const unsigned int index, const unsigned int af, const std
 		return false;
 	}
 
+	close(index);
+
 	int fd = ::socket(addr.ss_family, SOCK_DGRAM, 0);
 	if (fd < 0) {
 #if defined(_WIN32) || defined(_WIN64)
@@ -344,13 +346,13 @@ bool CUDPSocket::write(const unsigned char* buffer, unsigned int length, const s
 
 void CUDPSocket::close()
 {
-	for (int i = 0; i < UDP_SOCKET_MAX; i++)
-		close(m_fd[i]);
+	for (unsigned int i = 0; i < UDP_SOCKET_MAX; i++)
+		close(i);
 }
 
 void CUDPSocket::close(const unsigned int index)
 {
- 	if (m_fd[index] >= 0) {
+	if ((index < UDP_SOCKET_MAX) && (m_fd[index] >= 0)) {
 #if defined(_WIN32) || defined(_WIN64)
 		::closesocket(m_fd[index]);
 #else

From ffb4bdb0423ba23c88464f2ccd5742260a96ba70 Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Wed, 7 Apr 2021 19:56:28 +0100
Subject: [PATCH 22/23] Refactor the Golay 24,12,8 code and its uses.

---
 AMBEFEC.cpp    | 26 +++++++++++++++++---------
 Golay24128.cpp | 20 +++++++++++---------
 Golay24128.h   |  5 +++--
 M17Control.cpp | 10 +++++-----
 Version.h      |  2 +-
 YSFFICH.cpp    | 12 ++++++------
 6 files changed, 43 insertions(+), 32 deletions(-)

diff --git a/AMBEFEC.cpp b/AMBEFEC.cpp
index 4b28046..03f8ac2 100644
--- a/AMBEFEC.cpp
+++ b/AMBEFEC.cpp
@@ -793,22 +793,25 @@ unsigned int CAMBEFEC::regenerateIMBE(unsigned char* bytes) const
 
 unsigned int CAMBEFEC::regenerateDStar(unsigned int& a, unsigned int& b) const
 {
-	bool valid;
-
 	unsigned int orig_a = a;
 	unsigned int orig_b = b;
 
-	unsigned int data = CGolay24128::decode24128(a, valid);
-
-	a = CGolay24128::encode24128(data);
+	unsigned int data;
+	bool valid1 = CGolay24128::decode24128(a, data);
+	if (!valid1)
+		return 10U;
 
 	// The PRNG
 	unsigned int p = PRNG_TABLE[data];
 
 	b ^= p;
 
-	unsigned int datb = CGolay24128::decode24128(b, valid);
+	unsigned int datb;
+	bool valid2 = CGolay24128::decode24128(b, datb);
+	if (!valid2)
+		return 10U;
 
+	a = CGolay24128::encode24128(data);
 	b = CGolay24128::encode24128(datb);
 
 	b ^= p;
@@ -824,12 +827,17 @@ unsigned int CAMBEFEC::regenerateDStar(unsigned int& a, unsigned int& b) const
 
 unsigned int CAMBEFEC::regenerateDMR(unsigned int& a, unsigned int& b, unsigned int& c) const
 {
-	bool valid;
-
 	unsigned int orig_a = a;
 	unsigned int orig_b = b;
 
-	unsigned int data = CGolay24128::decode24128(a, valid);
+	unsigned int data;
+	bool valid = CGolay24128::decode24128(a, data);
+	if (!valid) {
+		a = 0xF00292U;
+		b = 0x0E0B20U;
+		c = 0x000000U;
+		return 10U;		// An invalid A block gives an error count of 10
+	}
 
 	a = CGolay24128::encode24128(data);
 
diff --git a/Golay24128.cpp b/Golay24128.cpp
index 715c8dc..22cef65 100644
--- a/Golay24128.cpp
+++ b/Golay24128.cpp
@@ -1090,23 +1090,25 @@ unsigned int CGolay24128::decode23127(unsigned int code)
 	return code >> 11;
 }
 
-unsigned int CGolay24128::decode24128(unsigned int input, bool& valid)
+bool CGolay24128::decode24128(unsigned int in, unsigned int& out)
 {
-	unsigned int syndrome = ::get_syndrome_23127(input >> 1);
+	unsigned int syndrome = ::get_syndrome_23127(in >> 1);
 	unsigned int error_pattern = DECODING_TABLE_23127[syndrome] << 1;
 
-	unsigned int output = input ^ error_pattern;
+	out = in ^ error_pattern;
 
-	valid = (CUtils::countBits(syndrome) < 3U) || !(CUtils::countBits(output) & 1);
+	bool valid = (CUtils::countBits(syndrome) < 3U) || !(CUtils::countBits(out) & 1);
 
-	return output >> 12;
+	out >>= 12;
+
+	return valid;
 }
 
-unsigned int CGolay24128::decode24128(unsigned char* bytes, bool& valid)
+bool CGolay24128::decode24128(unsigned char* in, unsigned int& out)
 {
-	assert(bytes != NULL);
+	assert(in != NULL);
 
-	unsigned int code = (bytes[0U] << 16) | (bytes[1U] << 8) | (bytes[2U] << 0);
+	unsigned int code = (in[0U] << 16) | (in[1U] << 8) | (in[2U] << 0);
 
-	return decode24128(code, valid);
+	return decode24128(code, out);
 }
diff --git a/Golay24128.h b/Golay24128.h
index 721dcbc..169b31a 100644
--- a/Golay24128.h
+++ b/Golay24128.h
@@ -25,8 +25,9 @@ public:
 	static unsigned int encode24128(unsigned int data);
 
 	static unsigned int decode23127(unsigned int code);
-	static unsigned int decode24128(unsigned int code, bool& valid);
-	static unsigned int decode24128(unsigned char* bytes, bool& valid);
+
+	static bool decode24128(unsigned int in, unsigned int& out);
+	static bool decode24128(unsigned char* in, unsigned int& out);
 };
 
 #endif
diff --git a/M17Control.cpp b/M17Control.cpp
index 653413d..f518037 100644
--- a/M17Control.cpp
+++ b/M17Control.cpp
@@ -212,11 +212,11 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 	}
 
 	if (m_rfState == RS_RF_LATE_ENTRY && data[0U] == TAG_DATA1) {
-		bool valid1, valid2, valid3, valid4;
-		unsigned int lich1 = CGolay24128::decode24128(data + 2U + M17_SYNC_LENGTH_BYTES + 0U, valid1);
-		unsigned int lich2 = CGolay24128::decode24128(data + 2U + M17_SYNC_LENGTH_BYTES + 3U, valid2);
-		unsigned int lich3 = CGolay24128::decode24128(data + 2U + M17_SYNC_LENGTH_BYTES + 6U, valid3);
-		unsigned int lich4 = CGolay24128::decode24128(data + 2U + M17_SYNC_LENGTH_BYTES + 9U, valid4);
+		unsigned int lich1, lich2, lich3, lich4;
+		bool valid1 = CGolay24128::decode24128(data + 2U + M17_SYNC_LENGTH_BYTES + 0U, lich1);
+		bool valid2 = CGolay24128::decode24128(data + 2U + M17_SYNC_LENGTH_BYTES + 3U, lich2);
+		bool valid3 = CGolay24128::decode24128(data + 2U + M17_SYNC_LENGTH_BYTES + 6U, lich3);
+		bool valid4 = CGolay24128::decode24128(data + 2U + M17_SYNC_LENGTH_BYTES + 9U, lich4);
 
 		if (!valid1 || !valid2 || !valid3 || !valid4)
 			return false;
diff --git a/Version.h b/Version.h
index 7dbf25d..9aea486 100644
--- a/Version.h
+++ b/Version.h
@@ -19,6 +19,6 @@
 #if !defined(VERSION_H)
 #define	VERSION_H
 
-const char* VERSION = "20210329";
+const char* VERSION = "20210407";
 
 #endif
diff --git a/YSFFICH.cpp b/YSFFICH.cpp
index ce37a7f..cbe3175 100644
--- a/YSFFICH.cpp
+++ b/YSFFICH.cpp
@@ -99,13 +99,13 @@ bool CYSFFICH::decode(const unsigned char* bytes)
 	unsigned char output[13U];
 	viterbi.chainback(output, 96U);
 
-	bool valid1, valid2, valid3, valid4;
-	unsigned int b0 = CGolay24128::decode24128(output + 0U, valid1);
-	unsigned int b1 = CGolay24128::decode24128(output + 3U, valid2);
-	unsigned int b2 = CGolay24128::decode24128(output + 6U, valid3);
-	unsigned int b3 = CGolay24128::decode24128(output + 9U, valid4);
+	unsigned int b0, b1, b2, b3;
+	bool valid0 = CGolay24128::decode24128(output + 0U, b0);
+	bool valid1 = CGolay24128::decode24128(output + 3U, b1);
+	bool valid2 = CGolay24128::decode24128(output + 6U, b2);
+	bool valid3 = CGolay24128::decode24128(output + 9U, b3);
 
-	if (!valid1 || !valid2 || !valid3 || !valid4)
+	if (!valid0 || !valid1 || !valid2 || !valid3)
 		return false;
 
 	m_fich[0U] = (b0 >> 4) & 0xFFU;

From dad34bea987a539adced43bde14b726fba2b0ae3 Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Thu, 8 Apr 2021 18:36:27 +0100
Subject: [PATCH 23/23] Don't send RPTCL on DMR under error conditions.

---
 DMRDirectNetwork.cpp  | 14 +++++++-------
 DMRDirectNetwork.h    |  2 +-
 DMRGatewayNetwork.cpp |  2 +-
 DMRGatewayNetwork.h   |  4 ++--
 DMRNetwork.h          |  4 ++--
 MMDVMHost.cpp         |  2 +-
 Version.h             |  4 ++--
 7 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/DMRDirectNetwork.cpp b/DMRDirectNetwork.cpp
index a378f7a..a27a646 100644
--- a/DMRDirectNetwork.cpp
+++ b/DMRDirectNetwork.cpp
@@ -321,11 +321,11 @@ bool CDMRDirectNetwork::isConnected() const
 	return (m_status == RUNNING);
 }
 
-void CDMRDirectNetwork::close()
+void CDMRDirectNetwork::close(bool sayGoodbye)
 {
 	LogMessage("Closing DMR Network");
 
-	if (m_status == RUNNING) {
+	if (sayGoodbye && (m_status == RUNNING)) {
 		unsigned char buffer[9U];
 		::memcpy(buffer + 0U, "RPTCL", 5U);
 		::memcpy(buffer + 5U, m_id, 4U);
@@ -377,7 +377,7 @@ void CDMRDirectNetwork::clock(unsigned int ms)
 	int length = m_socket.read(m_buffer, BUFFER_LENGTH, address, addrlen);
 	if (length < 0) {
 		LogError("DMR, Socket has failed, retrying connection to the master");
-		close();
+		close(false);
 		open();
 		return;
 	}
@@ -408,7 +408,7 @@ void CDMRDirectNetwork::clock(unsigned int ms)
 				   the Network sometimes times out and reaches here.
 				   We want it to reconnect so... */
 				LogError("DMR, Login to the master has failed, retrying network ...");
-				close();
+				close(false);
 				open();
 				return;
 			}
@@ -452,7 +452,7 @@ void CDMRDirectNetwork::clock(unsigned int ms)
 			}
 		} else if (::memcmp(m_buffer, "MSTCL", 5U) == 0) {
 			LogError("DMR, Master is closing down");
-			close();
+			close(false);
 			open();
 		} else if (::memcmp(m_buffer, "MSTPONG", 7U) == 0) {
 			m_timeoutTimer.start();
@@ -466,7 +466,7 @@ void CDMRDirectNetwork::clock(unsigned int ms)
 	m_timeoutTimer.clock(ms);
 	if (m_timeoutTimer.isRunning() && m_timeoutTimer.hasExpired()) {
 		LogError("DMR, Connection to the master has timed out, retrying connection");
-		close();
+		close(false);
 		open();
 	}
 }
@@ -635,7 +635,7 @@ bool CDMRDirectNetwork::write(const unsigned char* data, unsigned int length)
 	bool ret = m_socket.write(data, length, m_addr, m_addrLen);
 	if (!ret) {
 		LogError("DMR, Socket has failed when writing data to the master, retrying connection");
-		m_socket.close();
+		close(false);
 		open();
 		return false;
 	}
diff --git a/DMRDirectNetwork.h b/DMRDirectNetwork.h
index f6e0834..6df82cc 100644
--- a/DMRDirectNetwork.h
+++ b/DMRDirectNetwork.h
@@ -57,7 +57,7 @@ public:
 
 	virtual bool isConnected() const;
 
-	virtual void close();
+	virtual void close(bool sayGoodbye);
 
 private:
 	std::string      m_address;
diff --git a/DMRGatewayNetwork.cpp b/DMRGatewayNetwork.cpp
index 775a79d..f6dfe47 100644
--- a/DMRGatewayNetwork.cpp
+++ b/DMRGatewayNetwork.cpp
@@ -292,7 +292,7 @@ bool CDMRGatewayNetwork::isConnected() const
 	return (m_addrLen != 0);
 }
 
-void CDMRGatewayNetwork::close()
+void CDMRGatewayNetwork::close(bool sayGoodbye)
 {
 	LogMessage("DMR, Closing DMR Network");
 
diff --git a/DMRGatewayNetwork.h b/DMRGatewayNetwork.h
index bc00385..7bca94f 100644
--- a/DMRGatewayNetwork.h
+++ b/DMRGatewayNetwork.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2017,2018,2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2017,2018,2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -58,7 +58,7 @@ public:
 
 	virtual bool isConnected() const;
 
-	virtual void close();
+	virtual void close(bool sayGoodbye);
 
 private: 
 	std::string      m_addressStr;
diff --git a/DMRNetwork.h b/DMRNetwork.h
index 4a3c4d7..006e097 100644
--- a/DMRNetwork.h
+++ b/DMRNetwork.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2017,2018,2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2017,2018,2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -50,7 +50,7 @@ public:
 
 	virtual bool isConnected() const = 0;
 
-	virtual void close() = 0;
+	virtual void close(bool sayGoodbye) = 0;
 
 private: 
 };
diff --git a/MMDVMHost.cpp b/MMDVMHost.cpp
index 8409aac..ab8b5b1 100644
--- a/MMDVMHost.cpp
+++ b/MMDVMHost.cpp
@@ -1118,7 +1118,7 @@ int CMMDVMHost::run()
 	}
 
 	if (m_dmrNetwork != NULL) {
-		m_dmrNetwork->close();
+		m_dmrNetwork->close(true);
 		delete m_dmrNetwork;
 	}
 
diff --git a/Version.h b/Version.h
index 6e4502f..486d545 100644
--- a/Version.h
+++ b/Version.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015-2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015-2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -19,6 +19,6 @@
 #if !defined(VERSION_H)
 #define	VERSION_H
 
-const char* VERSION = "20210312";
+const char* VERSION = "20210408";
 
 #endif