Fix and simplify the M17 receiver.

M17RX.cpp

@@ -54,13 +54,9 @@ void CM17RX::databit(bool bit)
 {
   switch (m_state)  {
     case M17RXS_LINK_SETUP:
-      processLinkSetup(bit);
-      break;
     case M17RXS_STREAM:
-      processStream(bit);
-      break;
     case M17RXS_PACKET:
-      processPacket(bit);
+      processData(bit);
       break;
     default:
       processNone(bit);
@@ -114,7 +110,7 @@ void CM17RX::processNone(bool bit)
   }
 }
 
-void CM17RX::processLinkSetup(bool bit)
+void CM17RX::processData(bool bit)
 {
   m_bitBuffer <<= 1;
   if (bit)
@@ -126,30 +122,16 @@ void CM17RX::processLinkSetup(bool bit)
   if (m_bufferPtr > M17_FRAME_LENGTH_BITS)
     reset();
 
-  // Send a data frame to the host if the required number of bits have been received
+  // Only search for a link setup sync in the right place +-2 symbols
-  if (m_bufferPtr == M17_FRAME_LENGTH_BITS) {
+  if (m_bufferPtr >= (M17_SYNC_LENGTH_BITS - 2U) && m_bufferPtr <= (M17_SYNC_LENGTH_BITS + 2U)) {
-    m_lostCount--;
+    // Fuzzy matching of the stream sync bit sequence
-
+    if (countBits16(m_bitBuffer ^ M17_LINK_SETUP_SYNC_BITS) <= MAX_SYNC_BIT_RUN_ERRS) {
-    // Write data to host
+      DEBUG2("M17RX: found link setup sync, pos", m_bufferPtr - M17_SYNC_LENGTH_BITS);
-    m_outBuffer[0U] = 0x01U;
+      m_lostCount = MAX_SYNC_FRAMES;
-    writeRSSIHeader(m_outBuffer);
+      m_bufferPtr = M17_SYNC_LENGTH_BITS;
-
+      m_state     = M17RXS_LINK_SETUP;
-    // Start the next frame, but we don't know the type
+    }
-    reset();
   }
-}
-
-void CM17RX::processStream(bool bit)
-{
-  m_bitBuffer <<= 1;
-  if (bit)
-    m_bitBuffer |= 0x01U;
-
-  WRITE_BIT1(m_buffer, m_bufferPtr, bit);
-
-  m_bufferPtr++;
-  if (m_bufferPtr > M17_FRAME_LENGTH_BITS)
-    reset();
 
   // Only search for a stream sync in the right place +-2 symbols
   if (m_bufferPtr >= (M17_SYNC_LENGTH_BITS - 2U) && m_bufferPtr <= (M17_SYNC_LENGTH_BITS + 2U)) {
@@ -158,15 +140,27 @@ void CM17RX::processStream(bool bit)
       DEBUG2("M17RX: found stream sync, pos", m_bufferPtr - M17_SYNC_LENGTH_BITS);
       m_lostCount = MAX_SYNC_FRAMES;
       m_bufferPtr = M17_SYNC_LENGTH_BITS;
+      m_state     = M17RXS_STREAM;
     }
   }
 
-  // Send a stream frame to the host if the required number of bits have been received
+  // Only search for a packet sync in the right place +-2 symbols
+  if (m_bufferPtr >= (M17_SYNC_LENGTH_BITS - 2U) && m_bufferPtr <= (M17_SYNC_LENGTH_BITS + 2U)) {
+    // Fuzzy matching of the stream sync bit sequence
+    if (countBits16(m_bitBuffer ^ M17_STREAM_SYNC_BITS) <= MAX_SYNC_BIT_RUN_ERRS) {
+      DEBUG2("M17RX: found packet sync, pos", m_bufferPtr - M17_SYNC_LENGTH_BITS);
+      m_lostCount = MAX_SYNC_FRAMES;
+      m_bufferPtr = M17_SYNC_LENGTH_BITS;
+      m_state     = M17RXS_PACKET;
+    }
+  }
+
+  // Send a frame to the host if the required number of bits have been received
   if (m_bufferPtr == M17_FRAME_LENGTH_BITS) {
-    // We've not seen a stream sync for too long, signal RXLOST and change to RX_NONE
+    // We've not seen a sync for too long, signal RXLOST and change to RX_NONE
     m_lostCount--;
     if (m_lostCount == 0U) {
-      DEBUG1("M17RX: stream sync timed out, lost lock");
+      DEBUG1("M17RX: sync timed out, lost lock");
       io.setDecode(false);
       serial.writeM17Lost();
       reset();
@@ -174,7 +168,18 @@ void CM17RX::processStream(bool bit)
       // Write data to host
       m_outBuffer[0U]  = 0x00U;	// Stream data
       m_outBuffer[0U] |= m_lostCount == (MAX_SYNC_FRAMES - 1U) ? 0x01U : 0x00U;
-      writeRSSIData(m_outBuffer);
+
+      switch (m_state) {
+        case M17RXS_LINK_SETUP:
+          writeRSSILinkSetup(m_outBuffer);
+          break;
+        case M17RXS_STREAM:
+          writeRSSIStream(m_outBuffer);
+          break;
+        default:
+          writeRSSIPacket(m_outBuffer);
+          break;
+      }
 
       // Start the next frame
       ::memset(m_outBuffer, 0x00U, M17_FRAME_LENGTH_BYTES + 3U);
@@ -183,51 +188,7 @@ void CM17RX::processStream(bool bit)
   }
 }
 
-void CM17RX::processPacket(bool bit)
+void CM17RX::writeRSSILinkSetup(uint8_t* data)
-{
-  m_bitBuffer <<= 1;
-  if (bit)
-    m_bitBuffer |= 0x01U;
-
-  WRITE_BIT1(m_buffer, m_bufferPtr, bit);
-
-  m_bufferPtr++;
-  if (m_bufferPtr > M17_FRAME_LENGTH_BITS)
-    reset();
-
-  // Only search for a packet sync in the right place +-2 symbols
-  if (m_bufferPtr >= (M17_SYNC_LENGTH_BITS - 2U) && m_bufferPtr <= (M17_SYNC_LENGTH_BITS + 2U)) {
-    // Fuzzy matching of the packet sync bit sequence
-    if (countBits16(m_bitBuffer ^ M17_PACKET_SYNC_BITS) <= MAX_SYNC_BIT_RUN_ERRS) {
-      DEBUG2("M17RX: found packet sync, pos", m_bufferPtr - M17_SYNC_LENGTH_BITS);
-      m_lostCount = MAX_SYNC_FRAMES;
-      m_bufferPtr = M17_SYNC_LENGTH_BITS;
-    }
-  }
-
-  // Send a packet frame to the host if the required number of bits have been received
-  if (m_bufferPtr == M17_FRAME_LENGTH_BITS) {
-    // We've not seen a packet sync for too long, signal RXLOST and change to RX_NONE
-    m_lostCount--;
-    if (m_lostCount == 0U) {
-      DEBUG1("M17RX: packet sync timed out, lost lock");
-      io.setDecode(false);
-      serial.writeM17Lost();
-      reset();
-    } else {
-      // Write data to host
-      m_outBuffer[0U]  = 0x02U;	// Packet data
-      m_outBuffer[0U] |= m_lostCount == (MAX_SYNC_FRAMES - 1U) ? 0x01U : 0x00U;
-      writeRSSIData(m_outBuffer);
-
-      // Start the next frame
-      ::memset(m_outBuffer, 0x00U, M17_FRAME_LENGTH_BYTES + 3U);
-      m_bufferPtr = 0U;
-    }
-  }
-}
-
-void CM17RX::writeRSSIHeader(uint8_t* data)
 {
 #if defined(SEND_RSSI_DATA)
   uint16_t rssi = io.readRSSI();
@@ -235,13 +196,13 @@ void CM17RX::writeRSSIHeader(uint8_t* data)
   data[49U] = (rssi >> 8) & 0xFFU;
   data[50U] = (rssi >> 0) & 0xFFU;
 
-  serial.writeM17Header(data, M17_FRAME_LENGTH_BYTES + 3U);
+  serial.writeM17LinkSetup(data, M17_FRAME_LENGTH_BYTES + 3U);
 #else
-  serial.writeM17Header(data, M17_FRAME_LENGTH_BYTES + 1U);
+  serial.writeM17LinkSetup(data, M17_FRAME_LENGTH_BYTES + 1U);
 #endif
 }
 
-void CM17RX::writeRSSIData(uint8_t* data)
+void CM17RX::writeRSSIStream(uint8_t* data)
 {
 #if defined(SEND_RSSI_DATA)
   uint16_t rssi = io.readRSSI();
@@ -249,8 +210,23 @@ void CM17RX::writeRSSIData(uint8_t* data)
   data[49U] = (rssi >> 8) & 0xFFU;
   data[50U] = (rssi >> 0) & 0xFFU;
 
-  serial.writeM17Data(data, M17_FRAME_LENGTH_BYTES + 3U);
+  serial.writeM17Stream(data, M17_FRAME_LENGTH_BYTES + 3U);
 #else
-  serial.writeM17Data(data, M17_FRAME_LENGTH_BYTES + 1U);
+  serial.writeM17Stream(data, M17_FRAME_LENGTH_BYTES + 1U);
 #endif
 }
+
+void CM17RX::writeRSSIPacket(uint8_t* data)
+{
+#if defined(SEND_RSSI_DATA)
+  uint16_t rssi = io.readRSSI();
+
+  data[49U] = (rssi >> 8) & 0xFFU;
+  data[50U] = (rssi >> 0) & 0xFFU;
+
+  serial.writeM17Packet(data, M17_FRAME_LENGTH_BYTES + 3U);
+#else
+  serial.writeM17Packet(data, M17_FRAME_LENGTH_BYTES + 1U);
+#endif
+}
+

M17RX.h

@@ -46,11 +46,11 @@ private:
   uint16_t    m_lostCount;
 
   void processNone(bool bit);
-  void processLinkSetup(bool bit);
+  void processData(bool bit);
-  void processStream(bool bit);
+  void writeRSSILinkSetup(uint8_t* data);
-  void processPacket(bool bit);
+  void writeRSSIStream(uint8_t* data);
-  void writeRSSIHeader(uint8_t* data);
+  void writeRSSIPacket(uint8_t* data);
-  void writeRSSIData(uint8_t* data);
 };
 
 #endif
+

SerialPort.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2013,2015,2016,2018,2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2013,2015,2016,2018,2020,2021 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016 by Colin Durbridge G4EML
  *   Copyright (C) 2016,2017,2018,2019 by Andy Uribe CA6JAU
  *   Copyright (C) 2019 by Florian Wolters DF2ET
@@ -60,9 +60,10 @@ const uint8_t MMDVM_P25_LOST     = 0x32U;
 const uint8_t MMDVM_NXDN_DATA    = 0x40U;
 const uint8_t MMDVM_NXDN_LOST    = 0x41U;
 
-const uint8_t MMDVM_M17_HEADER   = 0x45U;
+const uint8_t MMDVM_M17_LINK_SETUP = 0x45U;
-const uint8_t MMDVM_M17_DATA     = 0x46U;
+const uint8_t MMDVM_M17_STREAM     = 0x46U;
-const uint8_t MMDVM_M17_LOST     = 0x47U;
+const uint8_t MMDVM_M17_PACKET     = 0x47U;
+const uint8_t MMDVM_M17_LOST       = 0x48U;
 
 const uint8_t MMDVM_POCSAG_DATA  = 0x50U;
 
@@ -865,7 +866,7 @@ void CSerialPort::process()
             }
             break;
 
-          case MMDVM_M17_HEADER:
+          case MMDVM_M17_LINK_SETUP:
             if (m_m17Enable) {
               if (m_modemState == STATE_IDLE || m_modemState == STATE_M17)
                 err = m17TX.writeData(m_buffer + 3U, m_len - 3U);
@@ -874,12 +875,12 @@ void CSerialPort::process()
               if (m_modemState == STATE_IDLE)
                 setMode(STATE_M17);
             } else {
-              DEBUG2("Received invalid M17 header", err);
+              DEBUG2("Received invalid M17 link setup data", err);
               sendNAK(err);
             }
             break;
 
-          case MMDVM_M17_DATA:
+          case MMDVM_M17_STREAM:
             if (m_m17Enable) {
               if (m_modemState == STATE_IDLE || m_modemState == STATE_M17)
                 err = m17TX.writeData(m_buffer + 3U, m_len - 3U);
@@ -888,7 +889,21 @@ void CSerialPort::process()
               if (m_modemState == STATE_IDLE)
                 setMode(STATE_M17);
             } else {
-              DEBUG2("Received invalid M17 data", err);
+              DEBUG2("Received invalid M17 stream data", err);
+              sendNAK(err);
+            }
+            break;
+
+          case MMDVM_M17_PACKET:
+            if (m_m17Enable) {
+              if (m_modemState == STATE_IDLE || m_modemState == STATE_M17)
+                err = m17TX.writeData(m_buffer + 3U, m_len - 3U);
+            }
+            if (err == 0U) {
+              if (m_modemState == STATE_IDLE)
+                setMode(STATE_M17);
+            } else {
+              DEBUG2("Received invalid M17 packet data", err);
               sendNAK(err);
             }
             break;
@@ -1248,7 +1263,7 @@ void CSerialPort::writeNXDNLost()
   writeInt(1U, reply, 3);
 }
 
-void CSerialPort::writeM17Header(const uint8_t* data, uint8_t length)
+void CSerialPort::writeM17LinkSetup(const uint8_t* data, uint8_t length)
 {
   if (m_modemState != STATE_M17 && m_modemState != STATE_IDLE)
     return;
@@ -1260,7 +1275,7 @@ void CSerialPort::writeM17Header(const uint8_t* data, uint8_t length)
 
   reply[0U] = MMDVM_FRAME_START;
   reply[1U] = 0U;
-  reply[2U] = MMDVM_M17_HEADER;
+  reply[2U] = MMDVM_M17_LINK_SETUP;
 
   uint8_t count = 3U;
   for (uint8_t i = 0U; i < length; i++, count++)
@@ -1271,7 +1286,7 @@ void CSerialPort::writeM17Header(const uint8_t* data, uint8_t length)
   writeInt(1U, reply, count);
 }
 
-void CSerialPort::writeM17Data(const uint8_t* data, uint8_t length)
+void CSerialPort::writeM17Stream(const uint8_t* data, uint8_t length)
 {
   if (m_modemState != STATE_M17 && m_modemState != STATE_IDLE)
     return;
@@ -1283,7 +1298,30 @@ void CSerialPort::writeM17Data(const uint8_t* data, uint8_t length)
 
   reply[0U] = MMDVM_FRAME_START;
   reply[1U] = 0U;
-  reply[2U] = MMDVM_M17_DATA;
+  reply[2U] = MMDVM_M17_STREAM;
+
+  uint8_t count = 3U;
+  for (uint8_t i = 0U; i < length; i++, count++)
+    reply[count] = data[i];
+
+  reply[1U] = count;
+
+  writeInt(1U, reply, count);
+}
+
+void CSerialPort::writeM17Packet(const uint8_t* data, uint8_t length)
+{
+  if (m_modemState != STATE_M17 && m_modemState != STATE_IDLE)
+    return;
+
+  if (!m_m17Enable)
+    return;
+
+  uint8_t reply[130U];
+
+  reply[0U] = MMDVM_FRAME_START;
+  reply[1U] = 0U;
+  reply[2U] = MMDVM_M17_PACKET;
 
   uint8_t count = 3U;
   for (uint8_t i = 0U; i < length; i++, count++)

SerialPort.h

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2018,2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2018,2020,2021 by Jonathan Naylor G4KLX
  *   Copyright (C) 2018 by Andy Uribe CA6JAU
  *
  *   This program is free software; you can redistribute it and/or modify
@@ -52,8 +52,9 @@ public:
   void writeNXDNData(const uint8_t* data, uint8_t length);
   void writeNXDNLost();
 
-  void writeM17Header(const uint8_t* data, uint8_t length);
+  void writeM17LinkSetup(const uint8_t* data, uint8_t length);
-  void writeM17Data(const uint8_t* data, uint8_t length);
+  void writeM17Stream(const uint8_t* data, uint8_t length);
+  void writeM17Packet(const uint8_t* data, uint8_t length);
   void writeM17Lost();
 
 #if defined(SEND_RSSI_DATA)

version.h

@@ -25,7 +25,7 @@
 #define VER_MAJOR       "1"
 #define VER_MINOR       "5"
 #define VER_REV         "2"
-#define VERSION_DATE    "20210102"
+#define VERSION_DATE    "20210314"
 
 #if defined(ZUMSPOT_ADF7021)
 #define BOARD_INFO      "ZUMspot"