diff --git a/sim/hwdbg/DebuggerModuleTestingBRAM/Makefile b/sim/hwdbg/DebuggerModuleTestingBRAM/Makefile
index 86631d9..43614f7 100644
--- a/sim/hwdbg/DebuggerModuleTestingBRAM/Makefile
+++ b/sim/hwdbg/DebuggerModuleTestingBRAM/Makefile
@@ -12,6 +12,7 @@ VERILOG_SOURCES += $(shell pwd)/../../../generated/InterpreterSendVersion.sv
 VERILOG_SOURCES += $(shell pwd)/../../../generated/InterpreterSendError.sv
 VERILOG_SOURCES += $(shell pwd)/../../../generated/InterpreterPortInformation.sv
 VERILOG_SOURCES += $(shell pwd)/../../../generated/ScriptExecutionEngine.sv
+VERILOG_SOURCES += $(shell pwd)/../../../generated/ScriptEngineEval.sv
 TOPLEVEL = DebuggerModuleTestingBRAM
 MODULE = test_DebuggerModuleTestingBRAM
 
diff --git a/sim/hwdbg/DebuggerModuleTestingBRAM/test_DebuggerModuleTestingBRAM.py b/sim/hwdbg/DebuggerModuleTestingBRAM/test_DebuggerModuleTestingBRAM.py
index cc918cc..c2fa60b 100644
--- a/sim/hwdbg/DebuggerModuleTestingBRAM/test_DebuggerModuleTestingBRAM.py
+++ b/sim/hwdbg/DebuggerModuleTestingBRAM/test_DebuggerModuleTestingBRAM.py
@@ -231,38 +231,38 @@ async def DebuggerModuleTestingBRAM_test(dut):
     #
     # Assert initial output is unknown
     #
-    assert LogicArray(dut.io_outputPin_0.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_1.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_2.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_3.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_4.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_5.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_6.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_7.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_8.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_9.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_10.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_11.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_12.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_13.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_14.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_15.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_16.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_17.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_18.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_19.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_20.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_21.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_22.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_23.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_24.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_25.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_26.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_27.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_28.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_29.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_30.value) == LogicArray("Z")
-    assert LogicArray(dut.io_outputPin_31.value) == LogicArray("Z")
+    assert LogicArray(dut.io_outputPin_0.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_1.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_2.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_3.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_4.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_5.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_6.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_7.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_8.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_9.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_10.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_11.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_12.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_13.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_14.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_15.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_16.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_17.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_18.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_19.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_20.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_21.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_22.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_23.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_24.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_25.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_26.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_27.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_28.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_29.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_30.value) == LogicArray("X")
+    assert LogicArray(dut.io_outputPin_31.value) == LogicArray("X")
 
     #
     # Create a 10ns period clock on port clock
diff --git a/src/main/scala/hwdbg/configs/configs.scala b/src/main/scala/hwdbg/configs/configs.scala
index 0744e80..0d643c4 100644
--- a/src/main/scala/hwdbg/configs/configs.scala
+++ b/src/main/scala/hwdbg/configs/configs.scala
@@ -66,10 +66,6 @@ object DebuggerConfigurations {
   //
   val BLOCK_RAM_DATA_WIDTH: Int = 32
 
-  //
-  // Single stage script symbol size (equal to sizeof(SYMBOL))
-  //
-  val SINGLE_STAGE_SCRIPT_SYMBOL_SIZE: Int = 32
 }
 
 /**
diff --git a/src/main/scala/hwdbg/main.scala b/src/main/scala/hwdbg/main.scala
index 8d538b0..bcee7d2 100644
--- a/src/main/scala/hwdbg/main.scala
+++ b/src/main/scala/hwdbg/main.scala
@@ -53,8 +53,8 @@ class DebuggerMain(
     //
     // Input/Output signals
     //
-    val inputPin = Input(Vec(numberOfPins, UInt((1.W)))) // input pins
-    val outputPin = Output(Vec(numberOfPins, UInt((1.W)))) // output pins
+    val inputPin = Input(Vec(numberOfPins, UInt(1.W))) // input pins
+    val outputPin = Output(Vec(numberOfPins, UInt(1.W))) // output pins
 
     //
     // Interrupt signals (lines)
@@ -213,7 +213,7 @@ object DebuggerMain {
       )
     )
 
-    val outputPin = Wire(Vec(numberOfPins, UInt((1.W))))
+    val outputPin = Wire(Vec(numberOfPins, UInt(1.W)))
     val psOutInterrupt = Wire(Bool())
     val rdWrAddr = Wire(UInt(bramAddrWidth.W))
     val wrEna = Wire(Bool())
diff --git a/src/main/scala/hwdbg/script/eval.scala b/src/main/scala/hwdbg/script/eval.scala
new file mode 100644
index 0000000..2e04a84
--- /dev/null
+++ b/src/main/scala/hwdbg/script/eval.scala
@@ -0,0 +1,110 @@
+/**
+ * @file
+ *   eval.scala
+ * @author
+ *   Sina Karvandi (sina@hyperdbg.org)
+ * @brief
+ *   Script execution engine
+ * @details
+ * @version 0.1
+ * @date
+ *   2024-05-17
+ *
+ * @copyright
+ *   This project is released under the GNU Public License v3.
+ */
+package hwdbg.script
+
+import chisel3._
+import chisel3.util._
+
+import hwdbg.configs._
+import hwdbg.stage._
+
+class ScriptEngineEval(
+    debug: Boolean = DebuggerConfigurations.ENABLE_DEBUG,
+    numberOfPins: Int = DebuggerConfigurations.NUMBER_OF_PINS,
+    maximumNumberOfStages: Int = DebuggerConfigurations.MAXIMUM_NUMBER_OF_STAGES,
+    portsConfiguration: Map[Int, Int] = DebuggerPorts.PORT_PINS_MAP
+) extends Module {
+
+  val io = IO(new Bundle {
+
+    //
+    // Chip signals
+    //
+    val en = Input(Bool()) // chip enable signal
+
+    //
+    // Evaluation symbol
+    //
+    val symbol = Input(new SYMBOL)
+    val nextStage = Output(UInt(log2Ceil(maximumNumberOfStages).W))
+
+    //
+    // Input/Output signals
+    //
+    val inputPin = Input(Vec(numberOfPins, UInt(1.W))) // input pins
+    val outputPin = Output(Vec(numberOfPins, UInt(1.W))) // output pins
+  })
+
+  //
+  // Output pins
+  //
+  // val outputPin = Wire(Vec(numberOfPins, UInt(1.W)))
+  // val nextStage = Wire(UInt(log2Ceil(maximumNumberOfStages).W))
+
+  //
+  // Connect the output signals
+  //
+  // io.nextStage := nextStage
+  // io.outputPin := outputPin
+  io.nextStage := 0.U
+  io.outputPin := io.inputPin
+
+}
+
+object ScriptEngineEval {
+
+  def apply(
+      debug: Boolean = DebuggerConfigurations.ENABLE_DEBUG,
+      numberOfPins: Int = DebuggerConfigurations.NUMBER_OF_PINS,
+      maximumNumberOfStages: Int = DebuggerConfigurations.MAXIMUM_NUMBER_OF_STAGES,
+      portsConfiguration: Map[Int, Int] = DebuggerPorts.PORT_PINS_MAP
+  )(
+      en: Bool,
+      symbol: SYMBOL,
+      inputPin: Vec[UInt]
+  ): (UInt, Vec[UInt]) = {
+
+    val scriptEngineEvalModule = Module(
+      new ScriptEngineEval(
+        debug,
+        numberOfPins,
+        maximumNumberOfStages,
+        portsConfiguration
+      )
+    )
+
+    val outputPin = Wire(Vec(numberOfPins, UInt(1.W)))
+    val nextStage = Wire(UInt(log2Ceil(maximumNumberOfStages).W))
+
+    //
+    // Configure the input signals
+    //
+    scriptEngineEvalModule.io.en := en
+    scriptEngineEvalModule.io.symbol := symbol
+    scriptEngineEvalModule.io.inputPin := inputPin
+
+    //
+    // Configure the output signals
+    //
+    nextStage := scriptEngineEvalModule.io.nextStage
+    outputPin := scriptEngineEvalModule.io.outputPin
+
+    //
+    // Return the output result
+    //
+    (nextStage, outputPin)
+  }
+}
diff --git a/src/main/scala/hwdbg/script/exec.scala b/src/main/scala/hwdbg/script/exec.scala
index 5f051f3..1abdecc 100644
--- a/src/main/scala/hwdbg/script/exec.scala
+++ b/src/main/scala/hwdbg/script/exec.scala
@@ -40,19 +40,19 @@ class ScriptExecutionEngine(
     //
     // Input/Output signals
     //
-    val inputPin = Input(Vec(numberOfPins, UInt((1.W)))) // input pins
-    val outputPin = Output(Vec(numberOfPins, UInt((1.W)))) // output pins
+    val inputPin = Input(Vec(numberOfPins, UInt(1.W))) // input pins
+    val outputPin = Output(Vec(numberOfPins, UInt(1.W))) // output pins
   })
 
   //
   // Output pins
   //
-  val outputPin = Wire(Vec(numberOfPins, UInt((1.W))))
+  val outputPin = Wire(Vec(numberOfPins, UInt(1.W)))
 
   //
   // Stage registers
   //
-  val stageRegs = Reg(new StageRegisters(debug, numberOfPins, maximumNumberOfStages))
+  val stageRegs = Reg(Vec(maximumNumberOfStages, new StageRegisters(debug, numberOfPins, maximumNumberOfStages)))
 
   // -----------------------------------------------------------------------
   //
@@ -66,12 +66,12 @@ class ScriptExecutionEngine(
       // At the first stage, the input registers should be passed to the
       // first registers set of the stage registers
       //
-      stageRegs.pinValues(i) := io.inputPin.asUInt
+      stageRegs(i).pinValues := io.inputPin
 
       //
       // Each pin start initially start from 0th target stage
       //
-      // stageRegs.targetStage(i) := 0.U
+      stageRegs(i).targetStage := 0.U
 
     } else if (i == (maximumNumberOfStages - 1)) {
 
@@ -79,22 +79,37 @@ class ScriptExecutionEngine(
       // At the last stage, the state registers should be passed to the output
       // Note: At this stage script symbol is useless
       //
-      for (j <- 0 until numberOfPins) {
-        outputPin(j) := stageRegs.pinValues(i)(j)
-      }
+      outputPin := stageRegs(i).pinValues
 
     } else {
 
       //
-      // At the normal (middle) stage, the state registers should be passed to
+      // Instantiate an eval engine for this stage
+      //
+      val (
+        nextStage,
+        outputPin
+      ) = ScriptEngineEval(
+        debug,
+        numberOfPins,
+        maximumNumberOfStages,
+        portsConfiguration
+      )(
+        io.en,
+        stageRegs(i).scriptSymbol,
+        stageRegs(i).pinValues
+      )
+
+      //
+      // At the normal (middle) stage, the result of state registers should be passed to
       // the next level of stage registers
       //
-      stageRegs.pinValues(i + 1) := stageRegs.pinValues(i)
+      stageRegs(i + 1).pinValues := outputPin
 
       //
       // Pass the target stage symbol number to the next stage
       //
-      // stageRegs.targetStage(i + 1) := stageRegs.targetStage(i) // Uncomment
+      stageRegs(i + 1).targetStage := nextStage
 
     }
   }
@@ -133,7 +148,7 @@ object ScriptExecutionEngine {
       )
     )
 
-    val outputPin = Wire(Vec(numberOfPins, UInt((1.W))))
+    val outputPin = Wire(Vec(numberOfPins, UInt(1.W)))
 
     //
     // Configure the input signals
diff --git a/src/main/scala/hwdbg/types/stage.scala b/src/main/scala/hwdbg/types/stage.scala
index f1e316f..1f834e8 100644
--- a/src/main/scala/hwdbg/types/stage.scala
+++ b/src/main/scala/hwdbg/types/stage.scala
@@ -20,14 +20,36 @@ import chisel3.util.log2Ceil
 
 import hwdbg.configs._
 
+//
+// Structure in C:
+//
+//
+// typedef struct SYMBOL {
+//	long long unsigned Type;
+//    long long unsigned Len;
+//    long long unsigned VariableType;
+//	long long unsigned Value;
+// } SYMBOL, * PSYMBOL;
+//
+
+/**
+ * @brief
+ *   The structure of SYMBOL used in script engine of HyperDbg
+ */
+class SYMBOL extends Bundle {
+  val Type = UInt(64.W) // long long unsigned is 64 bits
+  val Len = UInt(64.W)
+  val VariableType = UInt(64.W)
+  val Value = UInt(64.W)
+}
+
 class StageRegisters(
     debug: Boolean = DebuggerConfigurations.ENABLE_DEBUG,
     numberOfPins: Int = DebuggerConfigurations.NUMBER_OF_PINS,
-    maximumNumberOfStages: Int = DebuggerConfigurations.MAXIMUM_NUMBER_OF_STAGES,
-    singleStageScriptSymbolSize: Int = DebuggerConfigurations.SINGLE_STAGE_SCRIPT_SYMBOL_SIZE
+    maximumNumberOfStages: Int = DebuggerConfigurations.MAXIMUM_NUMBER_OF_STAGES
 ) extends Bundle {
-  val pinValues = Vec(maximumNumberOfStages, UInt(numberOfPins.W)) // The value of each pin in each stage (should be passed to the next stage)
-  val scriptSymbol = UInt(singleStageScriptSymbolSize.W) // Interpreted script symbol for the target stage (should NOT be passed to the next stage)
+  val pinValues = Vec(numberOfPins, UInt(1.W)) // The value of each pin in each stage (should be passed to the next stage)
+  val scriptSymbol = new SYMBOL // Interpreted script symbol for the target stage (should NOT be passed to the next stage)
   val targetStage = UInt(
     log2Ceil(maximumNumberOfStages).W
   ) // Target stage that needs to be executed for the current pin values (should be passed to the next stage)
diff --git a/src/main/scala/top.scala b/src/main/scala/top.scala
index 38f73a4..0a7ef79 100644
--- a/src/main/scala/top.scala
+++ b/src/main/scala/top.scala
@@ -39,8 +39,8 @@ class DebuggerModule(
     //
     // Input/Output signals
     //
-    val inputPin = Input(Vec(numberOfPins, UInt((1.W)))) // input pins
-    val outputPin = Output(Vec(numberOfPins, UInt((1.W)))) // output pins
+    val inputPin = Input(Vec(numberOfPins, UInt(1.W))) // input pins
+    val outputPin = Output(Vec(numberOfPins, UInt(1.W))) // output pins
 
     //
     // Interrupt signals (lines)
diff --git a/src/main/scala/top_test.scala b/src/main/scala/top_test.scala
index 8268d29..d2d9c5d 100644
--- a/src/main/scala/top_test.scala
+++ b/src/main/scala/top_test.scala
@@ -40,8 +40,8 @@ class DebuggerModuleTestingBRAM(
     //
     // Input/Output signals
     //
-    val inputPin = Input(Vec(numberOfPins, UInt((1.W)))) // input pins
-    val outputPin = Output(Vec(numberOfPins, UInt((1.W)))) // output pins
+    val inputPin = Input(Vec(numberOfPins, UInt(1.W))) // input pins
+    val outputPin = Output(Vec(numberOfPins, UInt(1.W))) // output pins
 
     //
     // Interrupt signals (lines)