diff --git a/include/CIRCT2Graph.h b/include/CIRCT2Graph.h
index 0c63991..e40f3df 100644
--- a/include/CIRCT2Graph.h
+++ b/include/CIRCT2Graph.h
@@ -34,8 +34,11 @@ class CIRCT2Graph {
   hw::HWModuleOp topModule;
   llvm::DenseMap<mlir::Value, Node*> valueNodeMap;
 
-  void processInputPort();
+  void processIoPort();
+  void processInputPort(hw::PortInfo port);
+  void processOutputPort(hw::PortInfo port);
   void processOperations();
+  void processOutputOp(hw::OutputOp op);
   void processConstantOp(hw::ConstantOp constantOp);
 };
 
diff --git a/src/CIRCT2Graph.cpp b/src/CIRCT2Graph.cpp
index d6d2fd0..87a195b 100644
--- a/src/CIRCT2Graph.cpp
+++ b/src/CIRCT2Graph.cpp
@@ -6,34 +6,68 @@
 #include "llvm/Support/Casting.h"
 #include "mlir/IR/Block.h"
 
+using llvm::dyn_cast;
+
 graph* CIRCT2Graph::generateGraph() {
   g = new graph();
-  processInputPort();
+  processIoPort();
   processOperations();
   return g;
 }
 
-void CIRCT2Graph::processInputPort() {
-  size_t inputPortIdx = 0;
-  for(size_t i = 0; i < topModule.getNumPorts(); i++) {
-    auto portInfo = topModule.getPort(i);
-    if(portInfo.isOutput()) continue;
+/// For each Input and Output port of TopModule. Generate NODE_IND and NODE_OUT
+void CIRCT2Graph::processIoPort() {
+  auto portList = topModule.getPortList();
+  for (auto& p : portList) {
+    //std::cout<< p.getName().str() << " "<< std::endl;
+    if (p.isInput()) {
+      processInputPort(p);
+    }else if (p.isOutput()) {
+      processOutputPort(p);
+    }else{ //InOut is not supproted!
+      Panic();
+    }
+  }
+}
+
+void CIRCT2Graph::processInputPort(hw::PortInfo portInfo) {
+    Assert(portInfo.isInput(),"");
     // 创建 typeInfo
-    TypeInfo* typeInfo = new TypeInfo();
-    typeInfo->set_sign(portInfo.type.isSignedInteger());
-    typeInfo->set_width(portInfo.type.getIntOrFloatBitWidth());
-    typeInfo->set_reset(UNCERTAIN);
+    auto typeInfo = std::make_unique<TypeInfo>();
+    if (isa<seq::ClockType>(portInfo.type)) {
+      typeInfo->set_sign(false);
+      typeInfo->set_width(1);
+      typeInfo->set_clock(true);
+      typeInfo->set_reset(UNCERTAIN);
+    } else {
+      typeInfo->set_sign(portInfo.type.isSignedInteger());
+      typeInfo->set_width(portInfo.type.getIntOrFloatBitWidth());
+      typeInfo->set_reset(UNCERTAIN);
+    }
     // 创建 node
     Node* node = new Node(NODE_INP); 
-    node->name = topModule.getPortName(i).str();
-    node->updateInfo(typeInfo);
+    node->name = portInfo.getName();
+    node->updateInfo(typeInfo.get());
     // 将 node 添加到图中
     g->input.push_back(node);
     // 将 value-node 关系添加到 map 中
-    mlir::Value portValue = topModule.getBodyRegion().front().getArgument(inputPortIdx);
+    mlir::Value portValue = topModule.getBodyRegion().front().getArgument(portInfo.argNum);
     valueNodeMap[portValue] = node;
-    inputPortIdx++;
-  }
+}
+
+void CIRCT2Graph::processOutputPort(hw::PortInfo portInfo) {
+  Assert(portInfo.isOutput(),"");
+
+  auto typeInfo = std::make_unique<TypeInfo>();
+  typeInfo->set_sign(portInfo.type.isSignedInteger());
+  typeInfo->set_width(portInfo.type.getIntOrFloatBitWidth());
+  typeInfo->set_reset(UNCERTAIN);
+
+  Node* node = new Node(NODE_OUT);
+  node->name = portInfo.getName();
+  node->updateInfo(typeInfo.get());
+
+  g->output.push_back(node);
 }
 
 void CIRCT2Graph::processOperations() {
@@ -43,14 +77,33 @@ void CIRCT2Graph::processOperations() {
 
   for (auto& op : body->getOperations()) {
     // GRH: add more operation in this branch
-    if (auto constantOp = llvm::dyn_cast<hw::ConstantOp>(op)) {
+    if (auto constantOp = dyn_cast<hw::ConstantOp>(op)) {
       processConstantOp(constantOp);
-    } else {
+    } else if (auto outputOp = dyn_cast<hw::OutputOp>(op)) {
+      processOutputOp(outputOp);
+    }else {
       Assert(false, "Unsupported operation: %s", op.getName().getStringRef().str().c_str());
     }
   }
 }
 
+/// hw.output sig1,sig2 : i1,i8
+/// Connect signals to the output of a module
+/// Order is defined by the hw.module's declaration
+void CIRCT2Graph::processOutputOp(hw::OutputOp op) {
+  auto operands = op.getOperands();
+  auto output_node_it = g->output.begin(); // C++ 17 doesn't have zip.
+  for (auto operand : operands) {
+    auto* node = *output_node_it;
+    auto* refNode = new ENode(valueNodeMap[operand]); // The node assigned to output
+    auto* expTree = new ExpTree(refNode, node);
+    node->assignTree.push_back(expTree);
+    ++output_node_it;
+  }
+}
+
+
+/// hw.constant 2 : i3
 void CIRCT2Graph::processConstantOp(hw::ConstantOp constantOp) {
   auto intType = llvm::dyn_cast<IntegerType>(constantOp.getType());
   Assert(intType, "hw.constant expects integer result type");