diff --git a/asm.cpp b/asm.cpp
index 125352f..9d28d19 100644
--- a/asm.cpp
+++ b/asm.cpp
@@ -208,7 +208,7 @@ void CLASS::print(uint32_t lineno)
 	}
 
 	uint32_t ct = 1;
-	if (obc > b)
+	if ((obc > b) && ((truncdata&0x01)==0))
 	{
 		ct = 0;
 		uint8_t db;
@@ -1293,7 +1293,7 @@ void CLASS::initpass(void)
 	passcomplete = false;
 	dumstartaddr = 0;
 	dumstart = 0;
-
+	truncdata=0;
 	variables.clear(); // clear the variables for each pass
 
 	while (!PCstack.empty())
@@ -1308,6 +1308,10 @@ void CLASS::initpass(void)
 	{
 		DOstack.pop();
 	}
+	while (!LSTstack.empty())
+	{
+		LSTstack.pop();
+	}
 	curLUP.clear();
 	curDO.clear();
 	savepath = "";
@@ -1622,6 +1626,7 @@ void CLASS::process(void)
 
 			line.eval_result = 0;
 			line.lineno = lineno + 1;
+			line.truncdata=truncdata;
 			//printf("lineno: %d %d |%s|\n",lineno,l,line.operand.c_str());
 
 			op = Poco::toLower(line.opcode);
diff --git a/asm.h b/asm.h
index 1ccab1c..a8f3b7b 100644
--- a/asm.h
+++ b/asm.h
@@ -189,6 +189,7 @@ public:
 	uint8_t linemx;
 	uint16_t commentcol;
 	bool showmx;
+	uint8_t truncdata;
 	uint32_t lineno;
 	uint32_t flags;
 	uint16_t opflags;
@@ -330,7 +331,6 @@ class T65816Asm : public TFileProcessor
 public:
 	// options
 	bool casesen;
-	bool listing;
 	bool showmx;
 	bool trackrep;
 	bool merlincompat;
@@ -356,10 +356,13 @@ public:
 	TOriginSection PC;
 	TLUPstruct curLUP;
 	TDOstruct curDO;
+	bool listing;
+	uint8_t truncdata; 	// for the TR opcode
 
 	std::stack<TOriginSection> PCstack;
 	std::stack<TLUPstruct> LUPstack;
 	std::stack<TDOstruct> DOstack;
+	std::stack<bool> LSTstack;
 
 	TPsuedoOp *psuedoops;
 
diff --git a/opcodes.cpp b/opcodes.cpp
index f4f8b20..b1f60a3 100644
--- a/opcodes.cpp
+++ b/opcodes.cpp
@@ -738,7 +738,7 @@ void CLASS::insertOpcodes(void)
 	pushopcode("PAG", 0x00, OP_PSUEDO, OPHANDLER(&CLASS::doPSEUDO));
 	pushopcode("TTL", 0x00, OP_PSUEDO, OPHANDLER(&CLASS::doPSEUDO));
 	pushopcode("SKP", 0x00, OP_PSUEDO, OPHANDLER(&CLASS::doPSEUDO));
-	pushopcode("TR",  0x00, OP_PSUEDO, OPHANDLER(&CLASS::doPSEUDO));
+	pushopcode("TR",  P_TR, OP_PSUEDO, OPHANDLER(&CLASS::doPSEUDO));
 	pushopcode("ASC", 0x00, OP_PSUEDO, OPHANDLER(&CLASS::doPSEUDO));
 	pushopcode("DCI", 0x00, OP_PSUEDO, OPHANDLER(&CLASS::doPSEUDO));
 	pushopcode("INV", 0x00, OP_PSUEDO, OPHANDLER(&CLASS::doPSEUDO));
diff --git a/psuedo.cpp b/psuedo.cpp
index 0cdde64..ff7f736 100644
--- a/psuedo.cpp
+++ b/psuedo.cpp
@@ -27,8 +27,8 @@ int CLASS::doDO(T65816Asm &a, MerlinLine &line, TSymbol &opinfo)
 	int err = 0;
 
 	std::string op = Poco::toUpper(line.opcode);
-	std::string oper = Poco::toUpper(line.operand_expr);
-	result32=0xFFFFFFFF;
+	std::string oper = line.operand_expr;
+	result32 = 0xFFFFFFFF;
 
 	if (op == "IF")
 	{
@@ -46,7 +46,7 @@ int CLASS::doDO(T65816Asm &a, MerlinLine &line, TSymbol &opinfo)
 		if (oper == "")
 		{
 			err = errIllegalCharOperand;
-			a.curDO.doskip=false;
+			a.curDO.doskip = false;
 			goto out;
 		}
 
@@ -66,7 +66,7 @@ int CLASS::doDO(T65816Asm &a, MerlinLine &line, TSymbol &opinfo)
 		}
 
 		result32 = eval_result & 0xFFFFFFFF;
-		a.curDO.doskip = (result32!=0) ? false : true;
+		a.curDO.doskip = (result32 != 0) ? false : true;
 
 		goto out;
 	}
@@ -98,7 +98,7 @@ int CLASS::doDO(T65816Asm &a, MerlinLine &line, TSymbol &opinfo)
 		{
 			// kind of a silent error here, just make sure we reinitialize
 			err = errUnexpectedOp;
-			a.curDO.doskip=false;
+			a.curDO.doskip = false;
 		}
 		goto out;
 	}
@@ -375,7 +375,15 @@ int CLASS::doLST(T65816Asm &a, MerlinLine &line, TSymbol &opinfo)
 	if (a.pass > 0)
 	{
 		s = Poco::toUpper(Poco::trim(line.operand_expr));
-		if ((s == "") || (s == "ON") || (line.expr_value > 0))
+		if (s == "RTN")
+		{
+			if (a.LSTstack.size())
+			{
+				a.listing = a.LSTstack.top();
+				a.LSTstack.pop();
+			}
+		}
+		else if ((s == "ON") || (line.expr_value > 0))
 		{
 			//printf("ON\n");
 			a.skiplist = true;
@@ -391,6 +399,29 @@ int CLASS::doLST(T65816Asm &a, MerlinLine &line, TSymbol &opinfo)
 	return (0);
 }
 
+int CLASS::doTR(T65816Asm &a, MerlinLine &line, TSymbol &opinfo)
+{
+	UNUSED(opinfo);
+
+	std::string s;
+	if (a.pass > 0)
+	{
+		s = Poco::toUpper(Poco::trim(line.operand_expr));
+		if (s == "ADR")
+		{
+			a.truncdata |= 0x03;
+		}
+		else if ((s == "ON") || (line.expr_value > 0))
+		{
+			a.truncdata |= 0x01;;
+		}
+		else if ((s == "OFF") || (line.expr_value == 0))
+		{
+			a.truncdata = 0x00;
+		}
+	}
+	return (0);
+}
 int CLASS::doHEX(T65816Asm &a, MerlinLine &line, TSymbol &opinfo)
 {
 	UNUSED(opinfo);
@@ -523,6 +554,9 @@ int CLASS::ProcessOpcode(T65816Asm &a, MerlinLine &line, TSymbol &opinfo)
 		case P_DO:
 			res = doDO(a, line, opinfo);
 			break;
+		case P_TR:
+			res=doTR(a,line,opinfo);
+			break;
 
 	}
 	return (res);
diff --git a/psuedo.h b/psuedo.h
index 00b1613..d59a38f 100644
--- a/psuedo.h
+++ b/psuedo.h
@@ -17,6 +17,7 @@ enum
 	P_DATA,
 	P_LUP,
 	P_DO,
+	P_TR,
 
 	P_MAX
 };
@@ -33,9 +34,8 @@ public:
 	int doHEX(T65816Asm &a, MerlinLine &line, TSymbol &opinfo);
 	int doDATA(T65816Asm &a, MerlinLine &line, TSymbol &opinfo);
 	int doLUP(T65816Asm &a, MerlinLine &line, TSymbol &opinfo);
-	int doDO(T65816Asm &a, MerlinLine &line, TSymbol &opinfo);;
-
-
+	int doDO(T65816Asm &a, MerlinLine &line, TSymbol &opinfo);
+	int doTR(T65816Asm &a, MerlinLine &line, TSymbol &opinfo);
 };
 
 #undef CLASS
\ No newline at end of file