diff --git a/app/src/main/java/com/example/hpos/data/constant/Constants.kt b/app/src/main/java/com/example/hpos/data/constant/Constants.kt
index dd70cb8..f0ee6d6 100644
--- a/app/src/main/java/com/example/hpos/data/constant/Constants.kt
+++ b/app/src/main/java/com/example/hpos/data/constant/Constants.kt
@@ -5,6 +5,7 @@ object Constants {
 
     const val WRITE_TIMEOUT_MILLIS = 30000   // 30 sec
     const val READ_TIMEOUT_MILLIS = 60000   // 1 min
+    const val DELAY_BETWEEN_COMMANDS: Long = 1000
 
     const val TEST_RIGHT_TOTAL_PIXEL = 3694
 //    const val TEST_RIGHT_TOTAL_PIXEL = 12
diff --git a/app/src/main/java/com/example/hpos/presentation/testRight/TestRightExpReference.kt b/app/src/main/java/com/example/hpos/presentation/testRight/TestRightExpReference.kt
index 9a2713c..4bac324 100644
--- a/app/src/main/java/com/example/hpos/presentation/testRight/TestRightExpReference.kt
+++ b/app/src/main/java/com/example/hpos/presentation/testRight/TestRightExpReference.kt
@@ -12,6 +12,7 @@ import androidx.fragment.app.Fragment
 import androidx.fragment.app.activityViewModels
 import com.example.hpos.R
 import com.example.hpos.data.DataHolder
+import com.example.hpos.data.constant.Constants
 import com.example.hpos.data.constant.TestRightCommands
 import com.example.hpos.databinding.FragmentTestRightExpReferenceBinding
 import com.example.hpos.presentation.UsbServiceListener
@@ -46,7 +47,7 @@ class TestRightExpReference : Fragment() {
 
         if (DataHolder.deviceConstant == null) {
             viewModel.progressBar.postValue(true)
-            Handler(Looper.getMainLooper()).postDelayed({ sendCmdToFetchDeviceConstant() }, 1000)
+            Handler(Looper.getMainLooper()).postDelayed({ sendCmdToFetchDeviceConstant() }, Constants.DELAY_BETWEEN_COMMANDS)
         }
     }
 
@@ -149,32 +150,22 @@ class TestRightExpReference : Fragment() {
         (activity as TestRightActivity).mService.eventDrivenWrite(TestRightCommands.led2Set50,
             object : UsbServiceListener {
                 override fun onUsbRead(data: ByteArray?) {
-//                    requireActivity().runOnUiThread {
                     data?.let {
                         val stringData = String(it)
                         fullReadOutput.append(stringData)
 
                         if (stringData.contains("OK", true)) {
                             Log.d(TAG, "onUsbRead() called in sendCmdToSetLed()")
-//                            viewModel.progressBar.postValue(false)
-//                                requireActivity().runOnUiThread {
-//                                    Thread.sleep(2000)
-//                                    sendCmdToAutoset()
-//                                }
 
                             Handler(Looper.getMainLooper()).postDelayed(
                                 Runnable {
                                     viewModel.progressBar.postValue(false)
                                     sendCmdToAutoset()
                                 },
-                                2000
+                                Constants.DELAY_BETWEEN_COMMANDS
                             )
-
-
-//                                sendCmdToAutoset()
                         }
                     }
-//                    }
                 }
 
                 override fun onUsbError(e: Exception?) {
@@ -205,7 +196,7 @@ class TestRightExpReference : Fragment() {
                                     viewModel.progressBar.postValue(false)
                                     sendCmdToRun()
                                 },
-                                2000
+                                Constants.DELAY_BETWEEN_COMMANDS
                             )
 
                         }
@@ -221,6 +212,7 @@ class TestRightExpReference : Fragment() {
     }
 
     private fun sendCmdToRun() {
+        Log.d(TAG, "sendCmdToRun() called")
         viewModel.progressBar.postValue(true)
         val fullReadOutput = StringBuilder()
         (activity as TestRightActivity).mService.eventDrivenWrite(TestRightCommands.run,
@@ -241,7 +233,7 @@ class TestRightExpReference : Fragment() {
                                     viewModel.progressBar.postValue(false)
                                     sendCmdToFetchLightIntensities()
                                 },
-                                2000
+                                Constants.DELAY_BETWEEN_COMMANDS
                             )
                         }
                     }
@@ -256,6 +248,7 @@ class TestRightExpReference : Fragment() {
     }
 
     private fun sendCmdToFetchLightIntensities() {
+        Log.d(TAG, "sendCmdToFetchLightIntensities() called")
         viewModel.progressBar.postValue(true)
         val fullReadOutput = StringBuilder()
         (activity as TestRightActivity).mService.eventDrivenWrite(TestRightCommands.printAll,
@@ -277,7 +270,7 @@ class TestRightExpReference : Fragment() {
                                     viewModel.progressBar.postValue(false)
                                     moveToSamplePage()
                                 },
-                                2000
+                                Constants.DELAY_BETWEEN_COMMANDS
                             )
                         }
                     }
@@ -312,7 +305,7 @@ class TestRightExpReference : Fragment() {
 //                            Runnable {
 //                                sendCmdToFetchDeviceConstant()
 //                            },
-//                            2000
+//                            Constants.DELAY_BETWEEN_COMMANDS
 //                        )
 //                    }
 //                }
@@ -366,7 +359,7 @@ class TestRightExpReference : Fragment() {
 //        val handler = Handler()
 //        handler.postDelayed(Runnable { // Do something after 5s = 5000ms
 //            mService.read()
-//        }, 10000)
+//        }, Constants.DELAY_BETWEEN_COMMANDS)
 //
 //    }
 }
\ No newline at end of file
diff --git a/app/src/main/java/com/example/hpos/presentation/testRight/TestRightExpSample.kt b/app/src/main/java/com/example/hpos/presentation/testRight/TestRightExpSample.kt
index 5830e0a..1214b38 100644
--- a/app/src/main/java/com/example/hpos/presentation/testRight/TestRightExpSample.kt
+++ b/app/src/main/java/com/example/hpos/presentation/testRight/TestRightExpSample.kt
@@ -10,6 +10,7 @@ import android.view.ViewGroup
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.activityViewModels
 import com.example.hpos.R
+import com.example.hpos.data.constant.Constants
 import com.example.hpos.data.constant.TestRightCommands
 import com.example.hpos.data.model.PatientData
 import com.example.hpos.data.model.TestRightResultType
@@ -121,7 +122,7 @@ class TestRightExpSample : Fragment() {
                                     viewModel.progressBar.postValue(false)
                                     sendCmdToFetchLightIntensities()
                                 },
-                                2000
+                                Constants.DELAY_BETWEEN_COMMANDS
                             )
 
                         }