From b09dba12139e9e33a2211a54c8fb2861ae22dd15 Mon Sep 17 00:00:00 2001
From: Harald Barth <haba@kth.se>
Date: Tue, 2 Aug 2022 01:24:01 +0200
Subject: [PATCH] Make packetPending private and new access routine. Implement
 schedulePacket without packetPending variable for ESP32

---
 DCC.cpp         |  2 +-
 DCCWaveform.cpp | 32 +++++++++++++++++++++++++++++++-
 DCCWaveform.h   |  6 ++++--
 3 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/DCC.cpp b/DCC.cpp
index f8ca7b1..0993f4c 100644
--- a/DCC.cpp
+++ b/DCC.cpp
@@ -587,7 +587,7 @@ void DCC::loop()  {
 
 void DCC::issueReminders() {
   // if the main track transmitter still has a pending packet, skip this time around.
-  if ( DCCWaveform::mainTrack.packetPending) return;
+  if ( DCCWaveform::mainTrack.getPacketPending()) return;
 
   // This loop searches for a loco in the speed table starting at nextLoco and cycling back around
   for (int reg=0;reg<MAX_LOCOS;reg++) {
diff --git a/DCCWaveform.cpp b/DCCWaveform.cpp
index ff0cd19..7cb59da 100644
--- a/DCCWaveform.cpp
+++ b/DCCWaveform.cpp
@@ -191,6 +191,9 @@ void DCCWaveform::schedulePacket(const byte buffer[], byte byteCount, byte repea
   packetPending = true;
   sentResetsSincePacket=0;
 }
+bool DCCWaveform::getPacketPending() {
+  return packetPending;
+}
 #endif
 
 #ifdef ARDUINO_ARCH_ESP32
@@ -203,7 +206,6 @@ RMTChannel *DCCWaveform::rmtProgChannel = NULL;
 
 DCCWaveform::DCCWaveform(byte preambleBits, bool isMain) {
   isMainTrack = isMain;
-  packetPending = false;
   requiredPreambles = preambleBits;
 }
 void DCCWaveform::begin() {
@@ -224,6 +226,34 @@ void DCCWaveform::begin() {
 }
 
 void DCCWaveform::schedulePacket(const byte buffer[], byte byteCount, byte repeats) {
+  if (byteCount > MAX_PACKET_SIZE) return; // allow for chksum
+  
+  byte checksum = 0;
+  for (byte b = 0; b < byteCount; b++) {
+    checksum ^= buffer[b];
+    pendingPacket[b] = buffer[b];
+  }
+  // buffer is MAX_PACKET_SIZE but pendingPacket is one bigger
+  pendingPacket[byteCount] = checksum;
+  pendingLength = byteCount + 1;
+  pendingRepeats = repeats;
+  sentResetsSincePacket=0;
+  {
+    int ret;
+    do {
+      if(isMainTrack)
+	ret = rmtMainChannel->RMTfillData(pendingPacket, pendingLength, pendingRepeats);
+      else
+	ret = rmtProgChannel->RMTfillData(pendingPacket, pendingLength, pendingRepeats);
+    } while(ret > 0);
+  }
+}
+
+bool DCCWaveform::getPacketPending() {
+  if(isMainTrack)
+    return rmtMainChannel->busy();
+  else
+    return rmtProgChannel->busy();
 }
 void DCCWaveform::loop() {
 }
diff --git a/DCCWaveform.h b/DCCWaveform.h
index d530b70..2a55189 100644
--- a/DCCWaveform.h
+++ b/DCCWaveform.h
@@ -54,11 +54,13 @@ class DCCWaveform {
     static DCCWaveform  progTrack;
     inline void clearRepeats() { transmitRepeats=0; }
     void schedulePacket(const byte buffer[], byte byteCount, byte repeats);
-    volatile bool packetPending;
     volatile byte sentResetsSincePacket;
+    bool getPacketPending();
     
   private:
-  
+#ifndef ARDUINO_ARCH_ESP32
+    volatile bool packetPending;
+#endif
     static void interruptHandler();
     void interrupt2();