From f7ead5cc0e6517d0965ae9c4a6237d41e1af8f8f Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Sat, 26 Dec 2020 12:42:16 +0000
Subject: [PATCH] Update the M17 sync vectors.

---
 M17Defines.h | 38 ++++++++++++++++++++++++--------------
 M17RX.cpp    | 12 ++++++------
 Version.h    |  2 +-
 3 files changed, 31 insertions(+), 21 deletions(-)

diff --git a/M17Defines.h b/M17Defines.h
index f98214b..de8ed31 100644
--- a/M17Defines.h
+++ b/M17Defines.h
@@ -30,29 +30,39 @@ const unsigned int M17_SYNC_LENGTH_BITS    = 16U;
 const unsigned int M17_SYNC_LENGTH_SYMBOLS = M17_SYNC_LENGTH_BITS / 2U;
 const unsigned int M17_SYNC_LENGTH_SAMPLES = M17_SYNC_LENGTH_SYMBOLS * M17_RADIO_SYMBOL_LENGTH;
 
-const uint8_t M17_HEADER_SYNC_BYTES[] = {0x5DU, 0xDDU};
-const uint8_t M17_DATA_SYNC_BYTES[]   = {0xDDU, 0xDDU};
+const uint8_t M17_LINK_SETUP_SYNC_BYTES[] = {0x55U, 0xF7U};
+const uint8_t M17_STREAM_SYNC_BYTES[]     = {0xFFU, 0x5DU};
+const uint8_t M17_PACKET_SYNC_BYTES[]     = {0x75U, 0xFFU};
 
 const uint8_t M17_SYNC_BYTES_LENGTH = 2U;
 
-const uint16_t M17_HEADER_SYNC_BITS = 0x5DDDU;
-const uint16_t M17_DAYA_SYNC_BITS   = 0xDDDDU;
+const uint16_t M17_LINK_SETUP_SYNC_BITS = 0x55F7U;
+const uint16_t M17_STREAM_SYNC_BITS     = 0xFF5DU;
+const uint16_t M17_PACKET_SYNC_BITS     = 0x75FFU;
 
-// 5     D      D      D
-// 01 01 11 01  11 01  11 01
-// +3 +3 -3 +3  -3 +3  -3 +3
+// 5     5     F     7
+// 01 01 01 01 11 11 01 11
+// +3 +3 +3 +3 -3 -3 +3 -3
 
-const int8_t M17_HEADER_SYNC_SYMBOLS_VALUES[] = {+3, +3, -3, +3, -3, +3, -3, +3};
+const int8_t M17_LINK_SETUP_SYNC_SYMBOLS_VALUES[] = {+3, +3, +3, +3, -3, -3, +3, -3};
 
-const uint8_t M17_HEADER_SYNC_SYMBOLS = 0xD5U;
+const uint8_t M17_LINK_SETUP_SYNC_SYMBOLS = 0xF2U;
 
-// D     D      D      D
-// 11 01 11 01  11 01  11 01
-// -3 +3 -3 +3  -3 +3  -3 +3
+// F     F     5     D
+// 11 11 11 11 01 01 11 01
+// -3 -3 -3 -3 +3 +3 -3 +3
 
-const int8_t M17_DATA_SYNC_SYMBOLS_VALUES[] = {-3, +3, -3, +3, -3, +3, -3, +3};
+const int8_t M17_STREAM_SYNC_SYMBOLS_VALUES[] = {-3, -3, -3, -3, +3, +3, -3, +3};
 
-const uint8_t M17_DATA_SYNC_SYMBOLS = 0x55U;
+const uint8_t M17_STREAM_SYNC_SYMBOLS = 0x0DU;
+
+// 7     5     F     F
+// 01 11 01 01 11 11 11 11
+// +3 -3 +3 +3 -3 -3 -3 -3
+
+const int8_t M17_PACKET_SYNC_SYMBOLS_VALUES[] = {+3, -3, +3, +3, -3, -3, -3, -3};
+
+const uint8_t M17_PACKET_SYNC_SYMBOLS = 0xB0U;
 
 #endif
 
diff --git a/M17RX.cpp b/M17RX.cpp
index 18a0a97..b5abe42 100644
--- a/M17RX.cpp
+++ b/M17RX.cpp
@@ -125,8 +125,8 @@ void CM17RX::samples(const q15_t* samples, uint16_t* rssi, uint8_t length)
 
 void CM17RX::processNone(q15_t sample)
 {
-  bool ret1 = correlateSync(M17_HEADER_SYNC_SYMBOLS, M17_HEADER_SYNC_SYMBOLS_VALUES, M17_HEADER_SYNC_BYTES);
-  bool ret2 = correlateSync(M17_DATA_SYNC_SYMBOLS, M17_DATA_SYNC_SYMBOLS_VALUES, M17_DATA_SYNC_BYTES);
+  bool ret1 = correlateSync(M17_LINK_SETUP_SYNC_SYMBOLS, M17_LINK_SETUP_SYNC_SYMBOLS_VALUES, M17_LINK_SETUP_SYNC_BYTES);
+  bool ret2 = correlateSync(M17_STREAM_SYNC_SYMBOLS,     M17_STREAM_SYNC_SYMBOLS_VALUES,     M17_STREAM_SYNC_BYTES);
 
   if (ret1 || ret2) {
     // On the first sync, start the countdown to the state change
@@ -166,10 +166,10 @@ void CM17RX::processHeader(q15_t sample)
 {
   if (m_minSyncPtr < m_maxSyncPtr) {
     if (m_dataPtr >= m_minSyncPtr && m_dataPtr <= m_maxSyncPtr)
-      correlateSync(M17_HEADER_SYNC_SYMBOLS, M17_HEADER_SYNC_SYMBOLS_VALUES, M17_HEADER_SYNC_BYTES);
+      correlateSync(M17_LINK_SETUP_SYNC_SYMBOLS, M17_LINK_SETUP_SYNC_SYMBOLS_VALUES, M17_LINK_SETUP_SYNC_BYTES);
   } else {
     if (m_dataPtr >= m_minSyncPtr || m_dataPtr <= m_maxSyncPtr)
-      correlateSync(M17_HEADER_SYNC_SYMBOLS, M17_HEADER_SYNC_SYMBOLS_VALUES, M17_HEADER_SYNC_BYTES);
+      correlateSync(M17_LINK_SETUP_SYNC_SYMBOLS, M17_LINK_SETUP_SYNC_SYMBOLS_VALUES, M17_LINK_SETUP_SYNC_BYTES);
   }
 
   if (m_dataPtr == m_endPtr) {
@@ -200,10 +200,10 @@ void CM17RX::processData(q15_t sample)
 {
   if (m_minSyncPtr < m_maxSyncPtr) {
     if (m_dataPtr >= m_minSyncPtr && m_dataPtr <= m_maxSyncPtr)
-      correlateSync(M17_DATA_SYNC_SYMBOLS, M17_DATA_SYNC_SYMBOLS_VALUES, M17_DATA_SYNC_BYTES);
+      correlateSync(M17_STREAM_SYNC_SYMBOLS, M17_STREAM_SYNC_SYMBOLS_VALUES, M17_STREAM_SYNC_BYTES);
   } else {
     if (m_dataPtr >= m_minSyncPtr || m_dataPtr <= m_maxSyncPtr)
-      correlateSync(M17_DATA_SYNC_SYMBOLS, M17_DATA_SYNC_SYMBOLS_VALUES, M17_DATA_SYNC_BYTES);
+      correlateSync(M17_STREAM_SYNC_SYMBOLS, M17_STREAM_SYNC_SYMBOLS_VALUES, M17_STREAM_SYNC_BYTES);
   }
 
   if (m_dataPtr == m_endPtr) {
diff --git a/Version.h b/Version.h
index 0944889..451d12b 100644
--- a/Version.h
+++ b/Version.h
@@ -19,7 +19,7 @@
 #if !defined(VERSION_H)
 #define  VERSION_H
 
-#define VERSION "20201214"
+#define VERSION "20201226"
 
 #endif