From 74664c137e884136042f05eacca805b3b8d49c9c Mon Sep 17 00:00:00 2001
From: Mathew Winters <mathew@winters.org.nz>
Date: Tue, 21 Apr 2026 20:12:53 +1200
Subject: [PATCH 1/2] Provides a 180 degree reverse function

On activity 18, the turntable will do a 180 degree turn.
Eg
<I 1 0 18>

I found that a turntable software didn't actually do a full reverse, which would be quite handy to have.
---
 IOFunctions.cpp        |  5 ++++-
 TurntableFunctions.cpp | 18 ++++++++++++++++++
 TurntableFunctions.h   |  2 ++
 3 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/IOFunctions.cpp b/IOFunctions.cpp
index 2907a1a..32bb454 100644
--- a/IOFunctions.cpp
+++ b/IOFunctions.cpp
@@ -398,7 +398,10 @@ void receiveEvent(int received) {
         Serial.println(F("DEBUG: Turn accessory pin off"));
       }
       setAccessory(LOW);
-
+#if TURNTABLE_EX_MODE == TURNTABLE
+    } else if (activity == 18 && !stepper.isRunning() && !calibrating) {
+      reverseTurntable(activity);
+#endif    
 #ifdef USE_RT_EX_TURNTABLE
     } else if ((activity >= 10) && (activity <= 17)) {
       setExtra(activity);
diff --git a/TurntableFunctions.cpp b/TurntableFunctions.cpp
index 0414cd8..10e6785 100644
--- a/TurntableFunctions.cpp
+++ b/TurntableFunctions.cpp
@@ -283,6 +283,24 @@ void moveToPosition(long steps, uint8_t phaseSwitch) {
   }
 }
 
+void reverseTurntable(uint8_t phaseSwitch){
+    // Calculate new target 180 degrees from lastTarget
+    long newTarget = lastTarget + halfTurnSteps;
+    if (newTarget >= fullTurnSteps) {
+      newTarget -= fullTurnSteps;
+    }
+    // Set phase if needed
+    setPhase(phaseSwitch);
+    // Move to new target
+    stepper.enableOutputs();
+    stepper.moveTo(newTarget);
+    lastTarget = newTarget;
+    lastStep = newTarget;
+
+    Serial.print(F("Reverseing Turntable: Rotating to "));
+    Serial.println(newTarget);
+}
+
 // Function to set phase.
 void setPhase(uint8_t phase) {
 #if RELAY_ACTIVE_STATE == HIGH
diff --git a/TurntableFunctions.h b/TurntableFunctions.h
index 4d300ed..18d8836 100644
--- a/TurntableFunctions.h
+++ b/TurntableFunctions.h
@@ -36,6 +36,7 @@ extern bool calibrating;
 extern uint8_t homed;
 extern AccelStepper stepper;
 extern long fullTurnSteps;
+extern long halfTurnSteps;
 extern long phaseSwitchStartSteps;
 extern long phaseSwitchStopSteps;
 extern long lastTarget;
@@ -56,6 +57,7 @@ void initiateHoming();
 void initiateCalibration();
 void setLEDActivity(uint8_t activity);
 void setAccessory(bool state);
+void reverseTurntable(uint8_t phaseSwitch);
 
 #ifdef USE_RT_EX_TURNTABLE
 void setExtra(uint8_t activity);

From f137a9184781ab89930e540f4cf099e41cf04256 Mon Sep 17 00:00:00 2001
From: Mathew Winters <mathew@winters.org.nz>
Date: Wed, 22 Apr 2026 18:42:21 +1200
Subject: [PATCH 2/2] Fix rotating 180 from home position.

---
 TurntableFunctions.cpp | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/TurntableFunctions.cpp b/TurntableFunctions.cpp
index 10e6785..e2d608d 100644
--- a/TurntableFunctions.cpp
+++ b/TurntableFunctions.cpp
@@ -183,6 +183,7 @@ void moveHome() {
 #endif
     stepper.setCurrentPosition(0);
     lastStep = 0;
+    lastTarget = 0;
     homed = 1;
     Serial.println(F("Turntable homed successfully"));
     if (debug) {
@@ -284,8 +285,12 @@ void moveToPosition(long steps, uint8_t phaseSwitch) {
 }
 
 void reverseTurntable(uint8_t phaseSwitch){
-    // Calculate new target 180 degrees from lastTarget
-    long newTarget = lastTarget + halfTurnSteps;
+    // Calculate new target 180 degrees from current logical position.
+    long baseTarget = lastStep % fullTurnSteps;
+    if (baseTarget < 0) {
+      baseTarget += fullTurnSteps;
+    }
+    long newTarget = baseTarget + halfTurnSteps;
     if (newTarget >= fullTurnSteps) {
       newTarget -= fullTurnSteps;
     }