diff --git a/DRAMSys/simulator/src/error/controllerECC.h b/DRAMSys/simulator/src/error/controllerECC.h
index beefe784..53dc469a 100644
--- a/DRAMSys/simulator/src/error/controllerECC.h
+++ b/DRAMSys/simulator/src/error/controllerECC.h
@@ -14,7 +14,7 @@ using namespace tlm;
 struct ControllerECC: sc_module
 {
 private:
-    map<int, unsigned char*> m_mDataPointer;
+	map<unsigned char*, unsigned char*> m_mDataPointer;
 
 public:
 	tlm_utils::multi_passthrough_target_socket<ControllerECC>    t_socket;
@@ -77,7 +77,7 @@ public:
 			trans.set_data_length(nBlocks*9);
 
             // store old data
-            m_mDataPointer[id] = trans.get_data_ptr();
+			m_mDataPointer[pDataECC] = trans.get_data_ptr();
 
 			// Set new data
 			trans.set_data_ptr(pDataECC);
@@ -89,12 +89,15 @@ public:
             // Get data length
             unsigned nDataLength = trans.get_data_length();
 
-            // store old data
-            m_mDataPointer[id] = trans.get_data_ptr();
+			// Create new pointer
+			nDataLength += nDataLength>>3;
+			unsigned char* new_ptr = new unsigned char [nDataLength];
 
-            // Set new data
-            nDataLength += nDataLength>>3;
-            trans.set_data_ptr(new unsigned char [nDataLength]);
+			// store old data ptr
+			m_mDataPointer[new_ptr] = trans.get_data_ptr();
+
+			// Set new data
+			trans.set_data_ptr(new_ptr);
 
             // Change transport data length
             trans.set_data_length(nDataLength);
@@ -189,7 +192,7 @@ public:
 			trans.set_data_length(nBlocks<<3);
 
             // load data pointer
-            auto it = m_mDataPointer.find(id);
+			auto it = m_mDataPointer.find(trans.get_data_ptr());
             assert(it != m_mDataPointer.end());
 
             unsigned char* pDataECC = it->second;
@@ -217,7 +220,7 @@ public:
             unsigned nDataLength = trans.get_data_length();
 
             // load data pointer
-            auto it = m_mDataPointer.find(id);
+			auto it = m_mDataPointer.find(trans.get_data_ptr());
             assert(it != m_mDataPointer.end());
 
             trans.set_data_ptr(it->second);