diff --git a/AppleWin/source/Debugger_DisassemblerData.cpp b/AppleWin/source/Debugger_DisassemblerData.cpp
new file mode 100644
index 00000000..3a5374f1
--- /dev/null
+++ b/AppleWin/source/Debugger_DisassemblerData.cpp
@@ -0,0 +1,367 @@
+/*
+AppleWin : An Apple //e emulator for Windows
+
+/* Description: Data Blocks shown in Disassembler
+ *
+ * Author: Copyright (C) 2009 Michael Pohoreski
+ */
+
+#include "StdAfx.h"
+#pragma  hdrstop
+
+// Disassembler Data ______________________________________________________________________________
+
+// __ Debugger Interaface ____________________________________________________________________________
+
+//===========================================================================
+WORD _CmdDefineByteRange(int nArgs,int iArg,DisasmData_t & tData_)
+{
+	WORD nAddress  = 0;
+	WORD nAddress2 = 0;
+	WORD nEnd      = 0;
+	int  nLen      = 0;
+
+	if( nArgs < 2 )
+	{
+		nAddress = g_nDisasmCurAddress;
+	}
+	else
+	{
+		RangeType_t eRange = Range_Get( nAddress, nAddress2, iArg);
+		if ((eRange == RANGE_HAS_END) ||
+			(eRange == RANGE_HAS_LEN))
+		{
+			Range_CalcEndLen( eRange, nAddress, nAddress2, nEnd, nLen );
+			//dArg = 2;
+		}
+		else
+		{
+				nAddress = g_aArgs[ 2 ].nValue;
+		}
+	}
+
+	if (!nLen)
+	{
+		nLen = 1;
+	}
+
+	tData_.nStartAddress = nAddress;
+	tData_.nEndAddress = nAddress + nLen;
+
+	char *pSymbolName = "";
+	if( nArgs )
+	{
+		pSymbolName = g_aArgs[ 1 ].sArg;
+		SymbolTable_Index_e eSymbolTable = SYMBOLS_ASSEMBLY;
+		// bRemoveSymbol = false // use arg[2]
+		// bUpdateSymbol = true // add the symbol to the table
+		SymbolUpdate( eSymbolTable, pSymbolName, nAddress, false, true ); 
+		// Note: need to call ConsoleUpdate(), as may print symbol has been updated
+	}
+	else
+	{
+		// TODO: 'DB' with no args, should define D_# DB $XX
+	}
+
+	strcpy( tData_.sSymbol, pSymbolName );
+
+	return nAddress;
+}
+
+// Undefine Data
+//===========================================================================
+Update_t CmdDisasmDataDefCode (int nArgs)
+{
+	// treat memory (bytes) as code
+	if (! ((nArgs <= 2) || (nArgs == 4)))
+	{
+		return Help_Arg_1( CMD_DISASM_CODE );
+	}
+
+	DisasmData_t tData;
+	int iArg = 2;
+	WORD nAddress = _CmdDefineByteRange( nArgs, iArg, tData );
+
+	// Need to iterate through all blocks
+	// DB TEST1 300:320
+	// DB TEST2 310:330
+	// DB TEST3 320:340
+	// !DB 300
+
+	DisasmData_t *pData = Disassembly_IsDataAddress( nAddress );
+	if( pData )
+	{
+		// Need to split the data
+//		*pData = tData;
+		Disassembly_AddData( tData );
+	}
+	else
+	{
+		Disassembly_DelData( tData );
+	}
+
+	return UPDATE_DISASM | ConsoleUpdate();
+}
+
+// List the data blocks
+//===========================================================================
+Update_t CmdDisasmDataList (int nArgs)
+{
+	// Need to iterate through all blocks
+	DisasmData_t* pData = NULL;
+	char sText[ CONSOLE_WIDTH ];
+	while( pData = Disassembly_Enumerate( pData ) )
+	{
+		// `TEST `300`:`320
+		sprintf( sText, "%s%s %s%04X%s:%s%04X\n"
+			, CHC_SYMBOL
+			, pData->sSymbol
+			, CHC_ADDRESS
+			, pData->nStartAddress
+			, CHC_ARG_SEP
+			, pData->nEndAddress
+		);
+		ConsolePrint( sText );
+	}
+
+	return UPDATE_DISASM | ConsoleUpdate();
+}
+
+// Common code
+//===========================================================================
+Update_t _CmdDisasmDataDefByteX (int nArgs)
+{
+	// DB
+	// DB symbol
+	// DB symbol address
+	// symbol range:range
+	int iCmd = NOP_BYTE_1 - g_aArgs[0].nValue;
+
+	if (! ((nArgs <= 2) || (nArgs == 4)))
+	{
+		return Help_Arg_1( CMD_DEFINE_DATA_BYTE1 + iCmd );
+	}
+
+	DisasmData_t tData;
+	int iArg = 2;
+	WORD nAddress = _CmdDefineByteRange( nArgs, iArg, tData );
+
+	tData.iDirective = FIRST_M_DIRECTIVE + ASM_M_DEFINE_BYTE;
+	tData.eElementType = NOP_BYTE_1 + iCmd;
+	tData.bSymbolLookup = false;
+	tData.nTargetAddress = 0;
+
+	// Already exists, so update
+	DisasmData_t *pData = Disassembly_IsDataAddress( nAddress );
+	if( pData )
+	{
+		*pData = tData;
+	}
+	else
+		Disassembly_AddData( tData );
+
+	return UPDATE_DISASM | ConsoleUpdate();
+}
+
+//===========================================================================
+Update_t _CmdDisasmDataDefWordX (int nArgs)
+{
+	// DW
+	// DW symbol
+	// DW symbol address
+	// symbol range:range
+	int iCmd = NOP_WORD_1 - g_aArgs[0].nValue;
+
+	if (! ((nArgs <= 2) || (nArgs == 4)))
+	{
+		return Help_Arg_1( CMD_DEFINE_DATA_WORD1 + iCmd );
+	}
+
+	DisasmData_t tData;
+	int iArg = 2;
+	WORD nAddress = _CmdDefineByteRange( nArgs, iArg, tData );
+
+	tData.iDirective = FIRST_M_DIRECTIVE + ASM_M_DEFINE_WORD;
+	tData.eElementType = NOP_WORD_1 + iCmd;
+	tData.bSymbolLookup = false;
+	tData.nTargetAddress = 0;
+
+	// Already exists, so update
+	DisasmData_t *pData = Disassembly_IsDataAddress( nAddress );
+	if( pData )
+	{
+		*pData = tData;
+	}
+	else
+		Disassembly_AddData( tData );
+
+	return UPDATE_DISASM | ConsoleUpdate();
+}
+
+//===========================================================================
+Update_t CmdDisasmDataDefAddress8H (int nArgs)
+{
+	return UPDATE_DISASM;
+}
+
+//===========================================================================
+Update_t CmdDisasmDataDefAddress8L (int nArgs)
+{
+	return UPDATE_DISASM;
+}
+
+//===========================================================================
+Update_t CmdDisasmDataDefAddress16 (int nArgs)
+{
+	return UPDATE_DISASM;
+}
+
+Update_t CmdDisasmDataDefByte1 ( int nArgs )
+{
+	g_aArgs[0].nValue = NOP_BYTE_1;
+	return _CmdDisasmDataDefByteX( nArgs );	
+}
+
+Update_t CmdDisasmDataDefByte2 ( int nArgs )
+{
+	g_aArgs[0].nValue = NOP_BYTE_2;
+	return _CmdDisasmDataDefByteX( nArgs );	
+}
+
+Update_t CmdDisasmDataDefByte4 ( int nArgs )
+{
+	g_aArgs[0].nValue = NOP_BYTE_4;
+	return _CmdDisasmDataDefByteX( nArgs );	
+}
+
+Update_t CmdDisasmDataDefByte8 ( int nArgs )
+{
+	g_aArgs[0].nValue = NOP_BYTE_8;
+	return _CmdDisasmDataDefByteX( nArgs );	
+}
+
+Update_t CmdDisasmDataDefWord1 ( int nArgs )
+{
+	g_aArgs[0].nValue = NOP_WORD_1;
+	return _CmdDisasmDataDefWordX( nArgs );	
+}
+
+Update_t CmdDisasmDataDefWord2 ( int nArgs )
+{
+	g_aArgs[0].nValue = NOP_WORD_2;
+	return _CmdDisasmDataDefWordX( nArgs );	
+}
+
+Update_t CmdDisasmDataDefWord4 ( int nArgs )
+{
+	g_aArgs[0].nValue = NOP_WORD_4;
+	return _CmdDisasmDataDefWordX( nArgs );	
+}
+
+Update_t CmdDisasmDataDefString ( int nArgs )
+{
+	return UPDATE_DISASM;
+}
+
+// __ Disassembler View Interface ____________________________________________________________________
+
+/// @param pCurrent NULL start a new serch, or continue enumerating
+//===========================================================================
+DisasmData_t* Disassembly_Enumerate( DisasmData_t *pCurrent )
+{
+	DisasmData_t *pData = NULL; // bIsNopcode = false
+	int nDataTargets = g_aDisassemblerData.size();
+
+	if( pCurrent )
+	{
+		pCurrent++;
+		pData = & g_aDisassemblerData[ nDataTargets ];
+		if( pCurrent < pData )
+			return pCurrent;
+		else
+			return NULL;
+	}
+	else
+	{
+		pData = & g_aDisassemblerData[ 0 ];
+		if( nDataTargets )
+			return pData;
+		else
+			return NULL;
+	}
+}
+
+// returns NULL if address has no data associated with it
+//===========================================================================
+DisasmData_t* Disassembly_IsDataAddress ( WORD nAddress )
+{
+	DisasmData_t *pData = NULL; // bIsNopcode = false
+	int nDataTargets = g_aDisassemblerData.size();
+
+	if( nDataTargets )
+	{
+		// TODO: Replace with binary search -- should store data in sorted order, via start address
+		pData = & g_aDisassemblerData[ 0 ];
+		for( int iTarget = 0; iTarget < nDataTargets; iTarget++ )
+		{
+			if( (nAddress >= pData->nStartAddress) && (nAddress < pData->nEndAddress) )
+			{
+				return pData;
+			}
+			pData++;
+		}
+		pData = NULL; // bIsNopCode = false
+	}
+	return pData;
+}
+
+//===========================================================================
+void Disassembly_AddData( DisasmData_t tData)
+{
+	g_aDisassemblerData.push_back( tData );
+}
+
+//===========================================================================
+void Disassembly_GetData ( WORD nBaseAddress, const DisasmData_t *pData, DisasmLine_t & line_ )
+{
+	line_.ClearFlags();
+
+	line_.iNoptype = pData->eElementType;
+	switch( pData->eElementType )
+	{
+		case NOP_BYTE_1:
+			line_.nOpbyte = 1;
+			break;
+		case NOP_BYTE_2:
+			line_.nOpbyte = 2;
+			break;
+		case NOP_WORD_1:
+			line_.nOpbyte= 2;
+			break;
+		case NOP_WORD_2:
+			line_.nOpbyte= 4;
+			break;
+		case NOP_STRING_APPLESOFT:
+			// scan memory for high byte
+			line_.nOpbyte = 8;
+			break;
+		default:
+			line_.nOpbyte = 1;
+			break;
+	}
+
+	FormatOpcodeBytes( nBaseAddress, line_ );
+
+	//pMnemonic = g_aOpcodes[ iOpcode ].sMnemonic;
+	line_.iNopcode = pData->iDirective;
+	strcpy( line_.sMnemonic, g_aAssemblerDirectives[ line_.iNopcode ].m_pMnemonic );
+
+	FormatNopcodeBytes( nBaseAddress, line_ );
+}
+
+//===========================================================================
+void Disassembly_DelData( DisasmData_t tData)
+{
+	// g_aDisassemblerData.erase( );
+}
+
diff --git a/AppleWin/source/Debugger_DisassemblerData.h b/AppleWin/source/Debugger_DisassemblerData.h
new file mode 100644
index 00000000..8d83b3fc
--- /dev/null
+++ b/AppleWin/source/Debugger_DisassemblerData.h
@@ -0,0 +1,55 @@
+#ifndef DEBUGGER_DISASSEMBLERDATA_H
+#define DEBUGGER_DISASSEMBLERDATA_H
+
+	enum NopcodeType_e
+	{
+		 NOP_BYTE_1 // 1 bytes/line
+		,NOP_BYTE_2 // 2 bytes/line
+		,NOP_BYTE_4 // 4 bytes/line
+		,NOP_BYTE_8 // 8 bytes/line
+		,NOP_WORD_1 // 1 words/line
+		,NOP_WORD_2 // 2 words/line
+		,NOP_WORD_4 // 4 words/line
+		,NOP_ADDRESS// 1 word/line
+		,NOP_HEX
+		,NOP_CHAR
+		,NOP_STRING_ASCII
+		,NOP_STRING_APPLE
+		,NOP_STRING_APPLESOFT
+		,NOP_FAC
+		,NUM_NOPCODE_TYPES
+	};
+
+	// Disassembler Data
+	// type symbol[start:end]
+	struct DisasmData_t
+	{
+		char sSymbol[ MAX_SYMBOLS_LEN+1 ];
+		WORD iDirective   ; // Assembler directive -> nopcode
+		WORD nStartAddress; // link to block [start,end)
+		WORD nEndAddress  ; 
+		WORD nArraySize   ; // Total bytes
+//		WORD nBytePerRow  ; // 1, 8
+		char eElementType; // 
+
+		// with symbol lookup
+		char bSymbolLookup ;
+		WORD nTargetAddress;
+	};
+
+	Update_t _CmdDisasmDataDefByteX    (int nArgs);
+	Update_t _CmdDisasmDataDefWordX    (int nArgs);
+
+// Data Disassembler ______________________________________________________________________________
+
+	int Disassembly_FindOpcode( WORD nAddress );
+	DisasmData_t* Disassembly_IsDataAddress( WORD nAddress );
+
+	void Disassembly_AddData( DisasmData_t tData);
+	void Disassembly_GetData ( WORD nBaseAddress, const DisasmData_t *pData_, DisasmLine_t & line_ );
+	void Disassembly_DelData( DisasmData_t tData);
+	DisasmData_t* Disassembly_Enumerate( DisasmData_t *pCurrent = NULL );
+
+	extern vector<DisasmData_t> g_aDisassemblerData;
+
+#endif
diff --git a/AppleWin/source/Debugger_Range.cpp b/AppleWin/source/Debugger_Range.cpp
new file mode 100644
index 00000000..c0dd270c
--- /dev/null
+++ b/AppleWin/source/Debugger_Range.cpp
@@ -0,0 +1,123 @@
+/*
+AppleWin : An Apple //e emulator for Windows
+
+Copyright (C) 1994-1996, Michael O'Brien
+Copyright (C) 1999-2001, Oliver Schmidt
+Copyright (C) 2002-2005, Tom Charlesworth
+Copyright (C) 2006-2009, Tom Charlesworth, Michael Pohoreski
+
+AppleWin is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+AppleWin is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with AppleWin; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+
+/* Description: Debugger Utility Range
+ *
+ * Author: Copyright (C) 2006-2009 Michael Pohoreski
+ */
+
+#include "StdAfx.h"
+#pragma  hdrstop
+
+// Util - Range _______________________________________________________________
+
+
+//===========================================================================
+bool Range_CalcEndLen( const RangeType_t eRange
+	, const WORD & nAddress1, const WORD & nAddress2
+	, WORD & nAddressEnd_, int & nAddressLen_ )
+{
+	bool bValid = false;
+
+	if (eRange == RANGE_HAS_LEN)
+	{
+		// BSAVE 2000,0  Len=0 End=n/a
+		// BSAVE 2000,1  Len=1 End=2000
+		// 0,FFFF [,)
+		// End =  FFFE = Len-1
+		// Len =  FFFF
+		nAddressLen_ = nAddress2;
+		int nTemp = nAddress1 + nAddressLen_ - 1;
+		if (nTemp > _6502_MEM_END)
+			nTemp = _6502_MEM_END;
+		nAddressEnd_ = nTemp;
+		bValid = true;
+	}
+	else
+	if (eRange == RANGE_HAS_END)
+	{
+		// BSAVE 2000:2000 Len=0, End=n/a
+		// BSAVE 2000:2001 Len=1, End=2000
+		// 0:FFFF [,]
+		// End =  FFFF
+		// Len = 10000 = End+1
+		nAddressEnd_ = nAddress2;
+		nAddressLen_ = nAddress2 - nAddress1 + 1;
+		bValid = true;
+	}
+
+	return bValid;
+}
+
+
+//===========================================================================
+RangeType_t Range_Get( WORD & nAddress1_, WORD & nAddress2_, const int iArg ) // =1
+{
+	nAddress1_ = (unsigned) g_aArgs[ iArg ].nValue; 
+	if (nAddress1_ > _6502_MEM_END)
+		nAddress1_ = _6502_MEM_END;
+
+	nAddress2_ = 0;
+	int nTemp  = 0;
+
+	RangeType_t eRange = RANGE_MISSING_ARG_2;
+
+	if (g_aArgs[ iArg + 1 ].eToken == TOKEN_COMMA)
+	{
+		// 0,FFFF [,) // Note the mathematical range
+		// End =  FFFE = Len-1
+		// Len =  FFFF
+		eRange = RANGE_HAS_LEN;
+		nTemp  = g_aArgs[ iArg + 2 ].nValue;
+		nAddress2_ = nTemp;
+	}
+	else
+	if (g_aArgs[ iArg + 1 ].eToken == TOKEN_COLON)
+	{
+		// 0:FFFF [,] // Note the mathematical range
+		// End =  FFFF
+		// Len = 10000 = End+1
+		eRange = RANGE_HAS_END;
+		nTemp  = g_aArgs[ iArg + 2 ].nValue;
+
+		// i.e.
+		// FFFF:D000
+		// 1    2    Temp
+		// FFFF      D000
+		//      FFFF
+		// D000
+		if (nAddress1_ > nTemp)
+		{
+			nAddress2_ = nAddress1_;
+			nAddress1_ = nTemp;
+		}
+		else
+			nAddress2_ = nTemp;
+	}
+
+	// .17 Bug Fix: D000,FFFF -> D000,CFFF (nothing searched!)
+//	if (nTemp > _6502_MEM_END)
+//		nTemp = _6502_MEM_END;
+
+	return eRange;
+}
diff --git a/AppleWin/source/Debugger_Range.h b/AppleWin/source/Debugger_Range.h
new file mode 100644
index 00000000..7663ef87
--- /dev/null
+++ b/AppleWin/source/Debugger_Range.h
@@ -0,0 +1,4 @@
+	RangeType_t Range_Get( WORD & nAddress1_, WORD &nAddress2_, const int iArg = 1 );
+	bool        Range_CalcEndLen( const RangeType_t eRange
+		, const WORD & nAddress1, const WORD & nAddress2
+		, WORD & nAddressEnd_, int & nAddressLen_ );