From efdbfcb03053ff88db13198520a01ecbaba80115 Mon Sep 17 00:00:00 2001
From: Harald Barth <haba@kth.se>
Date: Mon, 1 May 2023 20:18:32 +0200
Subject: [PATCH 1/3] Add serial output for sabertooth controller

---
 CommandDistributor.cpp | 30 ++++++++++++++++++++++++++++++
 SerialManager.cpp      |  3 +++
 2 files changed, 33 insertions(+)

diff --git a/CommandDistributor.cpp b/CommandDistributor.cpp
index 4b4159d..f788034 100644
--- a/CommandDistributor.cpp
+++ b/CommandDistributor.cpp
@@ -205,6 +205,36 @@ int16_t CommandDistributor::retClockTime() {
 void  CommandDistributor::broadcastLoco(byte slot) {
   DCC::LOCO * sp=&DCC::speedTable[slot];
   broadcastReply(COMMAND_TYPE, F("<l %d %d %d %l>\n"), sp->loco,slot,sp->speedCode,sp->functions);
+#ifdef SABERTOOTH
+  if (Serial2 && sp->loco == SABERTOOTH) {
+    static uint8_t rampingmode = 0;
+    bool direction = (sp->speedCode & 0x80) !=0; // true for forward
+    int32_t speed = sp->speedCode & 0x7f;
+    if (speed == 1) { // emergency stop
+      if (rampingmode != 1) {
+	rampingmode = 1;
+	Serial2.print("R1: 0\r\n");
+	Serial2.print("R2: 0\r\n");
+      }
+      Serial2.print("MD: 0\r\n");
+    } else {
+      if (speed != 0) {
+        // speed is here 2 to 127
+	speed = (speed - 1) * 1625 / 100;
+	speed = speed * (direction ? 1 : -1);
+	// speed is here -2047 to 2047
+      }
+      if (rampingmode != 2) {
+	rampingmode = 2;
+	Serial2.print("R1: 2047\r\n");
+	Serial2.print("R2: 2047\r\n");
+      }
+      Serial2.print("MD: ");
+      Serial2.print(speed);
+      Serial2.print("\r\n");
+    }
+  }
+#endif
 #ifdef CD_HANDLE_RING
   WiThrottle::markForBroadcast(sp->loco);
 #endif
diff --git a/SerialManager.cpp b/SerialManager.cpp
index 0ac567d..bacfceb 100644
--- a/SerialManager.cpp
+++ b/SerialManager.cpp
@@ -87,6 +87,9 @@ void SerialManager::init() {
     delay(1000);
   }
 #endif
+#ifdef SABERTOOTH
+  Serial2.begin(9600, SERIAL_8N1, 16, 17); // GPIO 16 RXD2; GPIO 17 TXD2 on ESP32
+#endif
 }
 
 void SerialManager::broadcast(char * stringBuffer) {

From 9d953c70b8a4df5b205c75e1f48588aef8c23f87 Mon Sep 17 00:00:00 2001
From: Harald Barth <haba@kth.se>
Date: Tue, 2 May 2023 23:51:17 +0200
Subject: [PATCH 2/3] use M1 and M2 instead of MD for motor control

---
 CommandDistributor.cpp | 5 ++++-
 GITHUB_SHA.h           | 2 +-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/CommandDistributor.cpp b/CommandDistributor.cpp
index f788034..9b61f78 100644
--- a/CommandDistributor.cpp
+++ b/CommandDistributor.cpp
@@ -229,7 +229,10 @@ void  CommandDistributor::broadcastLoco(byte slot) {
 	Serial2.print("R1: 2047\r\n");
 	Serial2.print("R2: 2047\r\n");
       }
-      Serial2.print("MD: ");
+      Serial2.print("M1: ");
+      Serial2.print(speed);
+      Serial2.print("\r\n");
+      Serial2.print("M2: ");
       Serial2.print(speed);
       Serial2.print("\r\n");
     }
diff --git a/GITHUB_SHA.h b/GITHUB_SHA.h
index f3e8efd..9564209 100644
--- a/GITHUB_SHA.h
+++ b/GITHUB_SHA.h
@@ -1 +1 @@
-#define GITHUB_SHA "devel-202304172140Z"
+#define GITHUB_SHA "devel-202305022149Z"

From c472f48d9303633433948bbd07451e3aa48e62b0 Mon Sep 17 00:00:00 2001
From: Harald Barth <haba@kth.se>
Date: Sat, 20 May 2023 14:57:00 +0200
Subject: [PATCH 3/3] Experimental support for sabertooth motor controller on
 ESP32

---
 GITHUB_SHA.h     |  2 +-
 config.example.h | 10 ++++++++++
 version.h        |  3 ++-
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/GITHUB_SHA.h b/GITHUB_SHA.h
index 9564209..355e2e9 100644
--- a/GITHUB_SHA.h
+++ b/GITHUB_SHA.h
@@ -1 +1 @@
-#define GITHUB_SHA "devel-202305022149Z"
+#define GITHUB_SHA "devel-202305201256Z"
diff --git a/config.example.h b/config.example.h
index 2a8a11a..058bc7a 100644
--- a/config.example.h
+++ b/config.example.h
@@ -224,5 +224,15 @@ The configuration file for DCC-EX Command Station
 //
 //#define SERIAL_BT_COMMANDS
 
+// SABERTOOTH
+//
+// This is a very special option and only useful if you happen to have a
+// sabertooth motor controller from dimension engineering configured to
+// take commands from and ESP32 via serial at 9600 baud from GPIO17 (TX)
+// and GPIO16 (RX, currently unused).
+// The number defined is the DCC address for which speed controls are sent
+// to the sabertooth controller _as_well_. Default: Undefined.
+//
+//#define SABERTOOTH 1
 
 /////////////////////////////////////////////////////////////////////////////////////
diff --git a/version.h b/version.h
index f168477..030cff6 100644
--- a/version.h
+++ b/version.h
@@ -4,7 +4,8 @@
 #include "StringFormatter.h"
 
 
-#define VERSION "4.2.47"
+#define VERSION "4.2.52"
+// 4.2.52 - Experimental support for sabertooth motor controller on ESP32
 // 4.2.47 - Correct response to <JA 0>
 // 4.2.46 - Support boards with inverted fault pin
 // 4.2.45 - Add ONCLOCKMINS to FastClock to allow hourly repeat events