From a245b9d119d2188c6daaa918fa5569b2a84f6510 Mon Sep 17 00:00:00 2001
From: Asbelos <asbelos@btinternet.com>
Date: Sun, 12 Jul 2020 00:11:30 +0100
Subject: [PATCH] Prog-Track-As-Siding

---
 DCC.cpp         |  4 +++-
 DCC.h           |  1 +
 DCCWaveform.cpp | 26 +++++++++++++++++++-------
 DCCWaveform.h   |  4 +++-
 4 files changed, 26 insertions(+), 9 deletions(-)

diff --git a/DCC.cpp b/DCC.cpp
index e5e9638..97564be 100644
--- a/DCC.cpp
+++ b/DCC.cpp
@@ -157,7 +157,9 @@ void DCC::writeCVBitMain(int cab, int cv, byte bNum, bool bValue)  {
   DCCWaveform::mainTrack.schedulePacket(b, nB, 4);
 }
 
-
+void DCC::setProgTrackSyncMain(bool on) {
+  DCCWaveform::progTrackSyncMain=on;
+}
 
 const ackOp PROGMEM WRITE_BIT0_PROG[] = {
      BASELINE,
diff --git a/DCC.h b/DCC.h
index f825e3d..4111263 100644
--- a/DCC.h
+++ b/DCC.h
@@ -63,6 +63,7 @@ class DCC {
   static void setAccessory(int aAdd, byte aNum, bool activate) ;
   static bool writeTextPacket( byte *b, int nBytes);
   static void setDebug(bool on);
+  static void setProgTrackSyncMain(bool on); // when true, prog track becomes driveable 
   
   // ACKable progtrack calls  bitresults callback 0,0 or -1, cv returns value or -1 
   static void  readCV(int cv, ACK_CALLBACK callback);
diff --git a/DCCWaveform.cpp b/DCCWaveform.cpp
index 8c14c43..e6ee023 100644
--- a/DCCWaveform.cpp
+++ b/DCCWaveform.cpp
@@ -26,7 +26,7 @@ DCCWaveform  DCCWaveform::progTrack(PREAMBLE_BITS_PROG, false, (int)(PROG_MAX_MI
 
 const int ACK_MIN_PULSE_RAW=65 / PROG_SENSE_FACTOR;
 
-
+bool DCCWaveform::progTrackSyncMain=false; 
 
 void DCCWaveform::begin() {
   Hardware::init();
@@ -102,6 +102,8 @@ void DCCWaveform::checkPowerOverload() {
   
   if (millis() - lastSampleTaken  < sampleDelay) return;
   lastSampleTaken = millis();
+  int tripValue= rawCurrentTripValue;
+  if (!isMainTrack && (ackPending || progTrackSyncMain))   tripValue=ACK_CURRENT_TRIP;
   
   switch (powerMode) {
     case POWERMODE::OFF:
@@ -110,11 +112,11 @@ void DCCWaveform::checkPowerOverload() {
     case POWERMODE::ON:
       // Check current
       lastCurrent = Hardware::getCurrentRaw(isMainTrack);
-      if (lastCurrent <= (ackPending?ACK_CURRENT_TRIP:rawCurrentTripValue))  sampleDelay = POWER_SAMPLE_ON_WAIT;
+      if (lastCurrent <= tripValue)  sampleDelay = POWER_SAMPLE_ON_WAIT;
       else {
         setPowerMode(POWERMODE::OVERLOAD);
         unsigned int mA=Hardware::getCurrentMilliamps(isMainTrack,lastCurrent);
-        unsigned int maxmA=Hardware::getCurrentMilliamps(isMainTrack,ackPending?ACK_CURRENT_TRIP:rawCurrentTripValue);
+        unsigned int maxmA=Hardware::getCurrentMilliamps(isMainTrack,tripValue);
         DIAG(F("\n*** %S TRACK POWER OVERLOAD current=%d max=%d ***\n"), isMainTrack ? F("MAIN") : F("PROG"), mA, maxmA);
         sampleDelay = POWER_SAMPLE_OVERLOAD_WAIT;
       }
@@ -140,19 +142,19 @@ bool DCCWaveform::interrupt1() {
   // otherwise can cause hangs in main loop waiting for the pendingBuffer.
   switch (state) {
     case 0:  // start of bit transmission
-      Hardware::setSignal(isMainTrack, HIGH);
+      setSignal(HIGH);
       state = 1;
       return true; // must call interrupt2 to set currentBit
 
     case 1:  // 58us after case 0
       if (currentBit) {
-        Hardware::setSignal(isMainTrack, LOW);
+        setSignal(LOW);
         state = 0;
       }
       else state = 2;
       break;
     case 2:  // 116us after case 0
-      Hardware::setSignal(isMainTrack, LOW);
+      setSignal(LOW);
       state = 3;
       break;
     case 3:  // finished sending zero bit
@@ -168,7 +170,17 @@ bool DCCWaveform::interrupt1() {
 
 }
 
-
+void DCCWaveform::setSignal(bool high) {
+  if (progTrackSyncMain) {
+    if (!isMainTrack) return; // ignore PROG track waveform while in sync
+    // set both tracks to same signal
+    Hardware::setSignal(true, high);
+    Hardware::setSignal(false, high);
+    return;     
+  }
+  Hardware::setSignal(isMainTrack,high);
+}
+      
 void DCCWaveform::interrupt2() {
   // set currentBit to be the next bit to be sent.
 
diff --git a/DCCWaveform.h b/DCCWaveform.h
index af562b0..3fc8015 100644
--- a/DCCWaveform.h
+++ b/DCCWaveform.h
@@ -62,13 +62,15 @@ class DCCWaveform {
     void setAckBaseline(bool debug);  //prog track only
     void setAckPending(bool debug);  //prog track only
     byte getAck(bool debug);               //prog track only 0=NACK, 1=ACK 2=keep waiting
-    
+    static bool progTrackSyncMain;  // true when prog track is a siding switched to main
+     
   private:
 
     static void interruptHandler();
     bool interrupt1();
     void interrupt2();
     void checkAck();
+    void setSignal(bool high);
     
     bool isMainTrack;