diff --git a/Tools/mqttecho/README.md b/Scripts/MQTTDemo/README.md
similarity index 98%
rename from Tools/mqttecho/README.md
rename to Scripts/MQTTDemo/README.md
index c0aac8d366..3f25da4bab 100644
--- a/Tools/mqttecho/README.md
+++ b/Scripts/MQTTDemo/README.md
@@ -1,7 +1,7 @@
 
 # Requirements
 
-- [Python](https://www.python.org/downloads/) - runs the demo script, `echo.py`, which runs broker and `echo` client
+- [Python](https://www.python.org/downloads/) - runs the demo script, `echo.py`, which runs broker and `echo` client; additional pip dependencies:
     - [Paho](https://www.eclipse.org/paho/index.php?page=clients/python/index.php) - used to implement the `echo` MQTT client
     - [Colorama](https://pypi.org/project/colorama/) - used to colorize log output of `echo.py`
 
diff --git a/Tools/mqttecho/echo.py b/Scripts/MQTTDemo/echo.py
similarity index 100%
rename from Tools/mqttecho/echo.py
rename to Scripts/MQTTDemo/echo.py
diff --git a/Tools/mqttecho/mosquitto.conf b/Scripts/MQTTDemo/mosquitto.conf
similarity index 100%
rename from Tools/mqttecho/mosquitto.conf
rename to Scripts/MQTTDemo/mosquitto.conf
diff --git a/Tools/mqttecho/passwords.txt b/Scripts/MQTTDemo/passwords.txt
similarity index 100%
rename from Tools/mqttecho/passwords.txt
rename to Scripts/MQTTDemo/passwords.txt
diff --git a/WHATS_NEW_UNIFIED.md b/WHATS_NEW_UNIFIED.md
index e4a0cbbaaf..57d015f87e 100644
--- a/WHATS_NEW_UNIFIED.md
+++ b/WHATS_NEW_UNIFIED.md
@@ -3,7 +3,7 @@ Version 3.5beta2_102
 * Duet3d 3.5beta2
 * Enable MQTT support (requires ESP firmware >= V2.1b3)
 * STM32F4: Add support for MCP2518FD SP CAN-FD interfaces
-* SYM32F4: Improved SPI1 support (allow interrupt operation)
+* STM32F4: Improved SPI1 support (allow interrupt operation)
 * Increase open files to 20
 * Ensure ESP32 modules are fully disabled by M552 s-1
 
diff --git a/src/GCodes/GCodeBuffer/StringParser.cpp b/src/GCodes/GCodeBuffer/StringParser.cpp
index f2f0f5516d..c9cf049bae 100644
--- a/src/GCodes/GCodeBuffer/StringParser.cpp
+++ b/src/GCodes/GCodeBuffer/StringParser.cpp
@@ -35,7 +35,7 @@ StringParser::StringParser(GCodeBuffer& gcodeBuffer) noexcept
 void StringParser::Init() noexcept
 {
 	gcodeLineEnd = 0;
-	commandStart = commandLength = 0;								// set both to zero so that calls to GetFilePosition don't return negative values
+	commandStart = commandCharsRead = 0;								// set both to zero so that calls to GetFilePosition don't return negative values
 	readPointer = -1;
 	hadLineNumber = hadChecksum = overflowed = seenExpression = false;
 	computedChecksum = 0;
@@ -74,6 +74,11 @@ inline void StringParser::StoreAndAddToChecksum(char c) noexcept
 // If true, it is complete and ready to be acted upon and 'indent' is the number of leading white space characters.
 bool StringParser::Put(char c) noexcept
 {
+	if (c != 0)
+	{
+		++commandCharsRead;
+	}
+
 	// We now discard CR if we are reading from file. It makes line number counting easier and it's unlikely that a pre-OSX Mac will be used with a Duet.
 	// When not reading from file we still accept CR as a line terminator, for compatibility with Putty and some other terminal emulators.
 	if (c == '\r' && gb.IsDoingFile())
@@ -81,11 +86,6 @@ bool StringParser::Put(char c) noexcept
 		return false;
 	}
 
-	if (c != 0)
-	{
-		++commandLength;
-	}
-
 	if (c == 0 || c == '\n' || c == '\r')
 	{
 		return LineFinished();
@@ -1167,7 +1167,7 @@ FilePosition StringParser::GetFilePosition() const noexcept
 # endif
 	   )
 	{
-		return gb.LatestMachineState().fileState.GetPosition() - gb.fileInput->BytesCached() - commandLength + commandStart;
+		return gb.LatestMachineState().fileState.GetPosition() - gb.fileInput->BytesCached() - commandCharsRead + commandStart;
 	}
 #endif
 	return noFilePosition;
diff --git a/src/GCodes/GCodeBuffer/StringParser.h b/src/GCodes/GCodeBuffer/StringParser.h
index 6510ab10ee..2120e9e48f 100644
--- a/src/GCodes/GCodeBuffer/StringParser.h
+++ b/src/GCodes/GCodeBuffer/StringParser.h
@@ -132,7 +132,7 @@ class StringParser
 	unsigned int commandStart;							// Index in the buffer of the command letter of this command
 	unsigned int parameterStart;
 	unsigned int commandEnd;							// Index in the buffer of one past the last character of this command
-	unsigned int commandLength;							// Number of characters we read to build this command including the final \r or \n
+	unsigned int commandCharsRead;							// Number of characters we read to build this command including the final \r or \n
 	unsigned int braceCount;							// how many nested { } we are inside
 	unsigned int gcodeLineEnd;							// Number of characters in the entire line of gcode
 	ParameterLettersBitmap parametersPresent;			// which parameters are present in this command
diff --git a/src/GCodes/GCodes.h b/src/GCodes/GCodes.h
index 5ec7b1fe48..cdd3766132 100644
--- a/src/GCodes/GCodes.h
+++ b/src/GCodes/GCodes.h
@@ -241,6 +241,12 @@ class GCodes
 		return workplaceCoordinates[GetConstMovementState(gb).currentCoordinateSystem][axis];
 	}
 
+#if SUPPORT_KEEPOUT_ZONES
+	size_t GetNumKeepoutZones() const noexcept { return (keepoutZone.IsDefined()) ? 1 : 0; }
+	bool IsKeepoutZoneDefined(size_t n) const noexcept { return n == 0 && keepoutZone.IsDefined(); }
+	const KeepoutZone *GetKeepoutZone(size_t) const noexcept { return &keepoutZone; }
+#endif
+
 #if SUPPORT_OBJECT_MODEL
 	float GetWorkplaceOffset(size_t axis, size_t workplaceNumber) const noexcept
 	{
diff --git a/src/GCodes/KeepoutZone.cpp b/src/GCodes/KeepoutZone.cpp
index a8b6e2530f..4fbbf60544 100644
--- a/src/GCodes/KeepoutZone.cpp
+++ b/src/GCodes/KeepoutZone.cpp
@@ -15,6 +15,42 @@
 
 #define ARC_DEBUG	0
 
+#define OBJECT_MODEL_FUNC(...) OBJECT_MODEL_FUNC_BODY(KeepoutZone, __VA_ARGS__)
+#define OBJECT_MODEL_FUNC_IF(...) OBJECT_MODEL_FUNC_IF_BODY(KeepoutZone, __VA_ARGS__)
+
+constexpr ObjectModelArrayTableEntry KeepoutZone::objectModelArrayTable[] =
+{
+	// 0. Axis coordinates
+	{
+		nullptr,					// no lock needed
+		[] (const ObjectModel *self, const ObjectExplorationContext&) noexcept -> size_t { return reprap.GetGCodes().GetTotalAxes(); },
+		[] (const ObjectModel *self, ObjectExplorationContext& context) noexcept -> ExpressionValue
+					{ return (((const KeepoutZone*)self)->axesChecked.IsBitSet(context.GetLastIndex())) ? ExpressionValue(self, 1) : ExpressionValue(nullptr); }
+	},
+};
+
+DEFINE_GET_OBJECT_MODEL_ARRAY_TABLE(KeepoutZone)
+
+constexpr ObjectModelTableEntry KeepoutZone::objectModelTable[] =
+{
+	// Within each group, these entries must be in alphabetical order
+	// 0. KeepoutZone members
+	{ "active",		OBJECT_MODEL_FUNC(self->active),											ObjectModelEntryFlags::none },
+	{ "coords",		OBJECT_MODEL_FUNC_ARRAY(0),													ObjectModelEntryFlags::none },
+	// 1. KeepoutZone.coords[] members
+	{ "max",		OBJECT_MODEL_FUNC(self->coords[context.GetLastIndex()][1]),					ObjectModelEntryFlags::none },
+	{ "min",		OBJECT_MODEL_FUNC(self->coords[context.GetLastIndex()][0]),					ObjectModelEntryFlags::none },
+};
+
+constexpr uint8_t KeepoutZone::objectModelTableDescriptor[] =
+{
+	2,				// number of sections
+	2,
+	2
+};
+
+DEFINE_GET_OBJECT_MODEL_TABLE(KeepoutZone)
+
 GCodeResult KeepoutZone::Configure(GCodeBuffer &gb, const StringRef &reply) THROWS(GCodeException)
 {
 	// See if any axes have been given
@@ -36,14 +72,21 @@ GCodeResult KeepoutZone::Configure(GCodeBuffer &gb, const StringRef &reply) THRO
 	}
 
 	// See if enabled or disabled
+	bool seen = false;
 	if (gb.Seen('S'))
 	{
+		seen = true;
 		active = (gb.GetUIValue() != 0);
 	}
 	else if (seenAxis)
 	{
 		active = true;
 	}
+
+	if (seenAxis || seen)
+	{
+		reprap.MoveUpdated();
+	}
 	else if (axesChecked.IsEmpty())
 	{
 		reply.copy("No keepout zone");
diff --git a/src/GCodes/KeepoutZone.h b/src/GCodes/KeepoutZone.h
index d1fd172763..70b89cad1e 100644
--- a/src/GCodes/KeepoutZone.h
+++ b/src/GCodes/KeepoutZone.h
@@ -12,16 +12,19 @@
 
 #if SUPPORT_KEEPOUT_ZONES
 
+#include <ObjectModel/ObjectModel.h>
 #include "GCodeException.h"
 #include <General/FreelistManager.h>
 
 // This class represents a keepout zone in the form of a hypercuboid
-class KeepoutZone
+class KeepoutZone INHERIT_OBJECT_MODEL
 {
 public:
 	// Constructor
 	KeepoutZone() noexcept : active(false) { }			// the BitMap default constructor will clear axesChecked
 
+	bool IsDefined() const noexcept { return !axesChecked.IsEmpty(); }
+
 	// Configure or report this zone
 	GCodeResult Configure(GCodeBuffer& gb, const StringRef& reply) THROWS(GCodeException);
 
@@ -40,6 +43,9 @@ class KeepoutZone
 							AxesBitmap cosineAxes, AxesBitmap sineAxes,
 							bool clockwise, bool wholeCircle) const noexcept;
 
+protected:
+	DECLARE_OBJECT_MODEL_WITH_ARRAYS
+
 private:
 	AxesBitmap axesChecked;				// which axes have defined limits
 	float coords[MaxAxes][2];			// the lower and upper limits for each axis, lower < upper
diff --git a/src/Movement/Move.cpp b/src/Movement/Move.cpp
index 7911f20f22..65bb1da29b 100644
--- a/src/Movement/Move.cpp
+++ b/src/Movement/Move.cpp
@@ -79,19 +79,27 @@ constexpr ObjectModelArrayTableEntry Move::objectModelArrayTable[] =
 		nullptr,					// no lock needed
 		[] (const ObjectModel *self, const ObjectExplorationContext&) noexcept -> size_t { return ARRAY_SIZE(rings); },
 		[] (const ObjectModel *self, ObjectExplorationContext& context) noexcept -> ExpressionValue { return ExpressionValue(&((const Move*)self)->rings[context.GetLastIndex()]); }
-	}
+	},
 
 #if SUPPORT_COORDINATE_ROTATION
-	,
 	// 3. Rotation centre coordinates
 	{
 		nullptr,					// no lock needed
 		[] (const ObjectModel *self, const ObjectExplorationContext&) noexcept -> size_t { return 2; },
 		[] (const ObjectModel *self, ObjectExplorationContext& context) noexcept -> ExpressionValue { return ExpressionValue(reprap.GetGCodes().GetRotationCentre(context.GetLastIndex())); }
-	}
-};
+	},
+#endif
 
+#if SUPPORT_KEEPOUT_ZONES
+	// 4. Keepout zone list
+	{
+		nullptr,					// no lock needed
+		[] (const ObjectModel *self, const ObjectExplorationContext&) noexcept -> size_t { return reprap.GetGCodes().GetNumKeepoutZones(); },
+		[] (const ObjectModel *self, ObjectExplorationContext& context) noexcept -> ExpressionValue
+				{ return (reprap.GetGCodes().IsKeepoutZoneDefined(context.GetLastIndex())) ? ExpressionValue(reprap.GetGCodes().GetKeepoutZone(context.GetLastIndex())) : ExpressionValue(nullptr); }
+	},
 #endif
+};
 
 DEFINE_GET_OBJECT_MODEL_ARRAY_TABLE(Move)
 
@@ -106,6 +114,9 @@ constexpr ObjectModelTableEntry Move::objectModelTable[] =
 	{ "currentMove",			OBJECT_MODEL_FUNC(self, 2),																		ObjectModelEntryFlags::live },
 	{ "extruders",				OBJECT_MODEL_FUNC_ARRAY(1),																		ObjectModelEntryFlags::live },
 	{ "idle",					OBJECT_MODEL_FUNC(self, 1),																		ObjectModelEntryFlags::none },
+#if SUPPORT_KEEPOUT_ZONES
+	{ "keepout",				OBJECT_MODEL_FUNC_ARRAY(4),																		ObjectModelEntryFlags::none },
+#endif
 	{ "kinematics",				OBJECT_MODEL_FUNC(self->kinematics),															ObjectModelEntryFlags::none },
 	{ "limitAxes",				OBJECT_MODEL_FUNC_NOSELF(reprap.GetGCodes().LimitAxes()),										ObjectModelEntryFlags::none },
 	{ "noMovesBeforeHoming",	OBJECT_MODEL_FUNC_NOSELF(reprap.GetGCodes().NoMovesBeforeHoming()),								ObjectModelEntryFlags::none },
@@ -119,7 +130,6 @@ constexpr ObjectModelTableEntry Move::objectModelTable[] =
 	{ "travelAcceleration",		OBJECT_MODEL_FUNC_NOSELF(InverseConvertAcceleration(reprap.GetGCodes().GetPrimaryMaxTravelAcceleration()), 1),		ObjectModelEntryFlags::none },
 	{ "virtualEPos",			OBJECT_MODEL_FUNC_NOSELF(reprap.GetGCodes().GetCurrentMovementState(context).latestVirtualExtruderPosition, 5),		ObjectModelEntryFlags::live },
 	{ "workplaceNumber",		OBJECT_MODEL_FUNC_NOSELF((int32_t)reprap.GetGCodes().GetPrimaryWorkplaceCoordinateSystemNumber() - 1),				ObjectModelEntryFlags::none },
-	{ "workspaceNumber",		OBJECT_MODEL_FUNC_NOSELF((int32_t)reprap.GetGCodes().GetPrimaryWorkplaceCoordinateSystemNumber()),					ObjectModelEntryFlags::obsolete },
 
 	// 1. Move.Idle members
 	{ "factor",					OBJECT_MODEL_FUNC_NOSELF(reprap.GetPlatform().GetIdleCurrentFactor(), 1),						ObjectModelEntryFlags::none },
@@ -180,7 +190,7 @@ constexpr ObjectModelTableEntry Move::objectModelTable[] =
 constexpr uint8_t Move::objectModelTableDescriptor[] =
 {
 	9 + SUPPORT_COORDINATE_ROTATION,
-	18 + SUPPORT_WORKPLACE_COORDINATES,
+	17 + SUPPORT_WORKPLACE_COORDINATES + SUPPORT_KEEPOUT_ZONES,
 	2,
 	5 + SUPPORT_LASER,
 	3,
diff --git a/src/Platform/Platform.cpp b/src/Platform/Platform.cpp
index 3f5a14584f..c97cff79a5 100644
--- a/src/Platform/Platform.cpp
+++ b/src/Platform/Platform.cpp
@@ -319,6 +319,7 @@ constexpr ObjectModelTableEntry Platform::objectModelTable[] =
 #ifndef DUET_NG
 	{ "percentStstCurrent",	OBJECT_MODEL_FUNC((int32_t)(self->GetMotorCurrent(context.GetLastIndex(), 917))),								ObjectModelEntryFlags::none },
 #endif
+	{ "reducedAcceleration", OBJECT_MODEL_FUNC(InverseConvertAcceleration(self->Acceleration(context.GetLastIndex(), true)), 1),			ObjectModelEntryFlags::none },
 	{ "speed",				OBJECT_MODEL_FUNC(InverseConvertSpeedToMmPerMin(self->MaxFeedrate(context.GetLastIndex())), 1),					ObjectModelEntryFlags::none },
 	{ "stepsPerMm",			OBJECT_MODEL_FUNC(self->driveStepsPerUnit[context.GetLastIndex()], 2),											ObjectModelEntryFlags::none },
 	{ "userPosition",		OBJECT_MODEL_FUNC_NOSELF(reprap.GetGCodes().GetUserCoordinate(reprap.GetGCodes().GetCurrentMovementState(context), context.GetLastIndex()), 3), ObjectModelEntryFlags::live },
@@ -326,7 +327,7 @@ constexpr ObjectModelTableEntry Platform::objectModelTable[] =
 	{ "workplaceOffsets",	OBJECT_MODEL_FUNC_ARRAY(1),																						ObjectModelEntryFlags::none },
 
 	// 4. move.extruders[] members
-	{ "acceleration",		OBJECT_MODEL_FUNC(InverseConvertAcceleration(self->NormalAcceleration(ExtruderToLogicalDrive(context.GetLastIndex()))), 1),					ObjectModelEntryFlags::none },
+	{ "acceleration",		OBJECT_MODEL_FUNC(InverseConvertAcceleration(self->NormalAcceleration(ExtruderToLogicalDrive(context.GetLastIndex()))), 1),				ObjectModelEntryFlags::none },
 	{ "current",			OBJECT_MODEL_FUNC((int32_t)(self->GetMotorCurrent(ExtruderToLogicalDrive(context.GetLastIndex()), 906))),								ObjectModelEntryFlags::none },
 	{ "driver",				OBJECT_MODEL_FUNC(self->extruderDrivers[context.GetLastIndex()]),																		ObjectModelEntryFlags::none },
 	{ "factor",				OBJECT_MODEL_FUNC_NOSELF(reprap.GetGCodes().GetExtrusionFactor(context.GetLastIndex()), 3),												ObjectModelEntryFlags::none },
@@ -388,10 +389,10 @@ constexpr uint8_t Platform::objectModelTableDescriptor[] =
 	0,																		// section 2: vIn
 #endif
 #ifdef DUET_NG	// Duet WiFi/Ethernet doesn't have settable standstill current
-	20,																		// section 3: move.axes[]
+	21,																		// section 3: move.axes[]
 	15,																		// section 4: move.extruders[]
 #else
-	21,																		// section 3: move.axes[]
+	22,																		// section 3: move.axes[]
 	16,																		// section 4: move.extruders[]
 #endif
 	3,																		// section 5: move.extruders[].nonlinear
diff --git a/src/Tools/Spindle.cpp b/src/Tools/Spindle.cpp
index 5b45675a49..eff81e056a 100644
--- a/src/Tools/Spindle.cpp
+++ b/src/Tools/Spindle.cpp
@@ -152,11 +152,8 @@ void Spindle::SetRpm(uint32_t rpm) noexcept
 
 void Spindle::SetState(const SpindleState newState) noexcept
 {
-	if (state != newState)
-	{
-		state = newState;
-		SetRpm(configuredRpm);				// Depending on the configured SpindleState this might actually stop the spindle
-	}
+	state = newState;
+	SetRpm(configuredRpm);					// depending on the configured SpindleState this might actually stop the spindle
 }
 
 // End
diff --git a/src/Version.h b/src/Version.h
index 246878cf2d..b9ef126224 100644
--- a/src/Version.h
+++ b/src/Version.h
@@ -10,7 +10,7 @@
 
 #ifndef VERSION
 // Note: the complete VERSION string must be in standard version number format and must not contain spaces! This is so that DWC can parse it.
-# define MAIN_VERSION	"3.5beta2_102"
+# define MAIN_VERSION	"3.5beta2+_103"
 # ifdef USE_CAN0
 #  define VERSION_SUFFIX	"(CAN0)"
 # else