diff --git a/app/build.gradle b/app/build.gradle
index bdf287e..4ac8e6d 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -1,13 +1,13 @@
 apply plugin: 'com.android.application'
 
 android {
-    compileSdkVersion 30
+    compileSdkVersion 31
     defaultConfig {
         applicationId "com.csl.cs108ademoapp"
         minSdkVersion 19
-        targetSdkVersion 30
+        targetSdkVersion 31
         versionCode 34
-        versionName "2.3.0"
+        versionName "2.3.4"
     }
 }
 
diff --git a/app/release/cs108ademo-20220224-v2.3.4-app-release.zip b/app/release/cs108ademo-20220224-v2.3.4-app-release.zip
new file mode 100644
index 0000000..8391ec3
Binary files /dev/null and b/app/release/cs108ademo-20220224-v2.3.4-app-release.zip differ
diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 813f986..9a9ab10 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -18,6 +18,7 @@
 
         <service android:name=".CustomIME"
             android:label="@string/app_ime"
+            android:exported="true"
             android:permission="android.permission.BIND_INPUT_METHOD">
             <intent-filter>
                 <action android:name="android.view.InputMethod" />
@@ -27,6 +28,7 @@
 
         <activity
             android:name=".MainActivity"
+            android:exported="true"
             android:screenOrientation="portrait">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
diff --git a/app/src/main/java/com/csl/cs108ademoapp/InventoryRfidTask.java b/app/src/main/java/com/csl/cs108ademoapp/InventoryRfidTask.java
index 9b5e646..2f7e955 100644
--- a/app/src/main/java/com/csl/cs108ademoapp/InventoryRfidTask.java
+++ b/app/src/main/java/com/csl/cs108ademoapp/InventoryRfidTask.java
@@ -425,7 +425,7 @@ else if (strTidCompared.matches("E2806894") && MainActivity.mDid.matches("E28068
 
                     double rssiGeiger = rssi;
                     if (MainActivity.mCs108Library4a.getRssiDisplaySetting() != 0)
-                        rssiGeiger -= 106.98;
+                        rssiGeiger -= MainActivity.mCs108Library4a.dBuV_dBm_constant;
                     if (geigerTagRssiView != null)
                         geigerTagRssiView.setText(String.format("%.1f", rssiGeiger));
                     if (geigerTagGotView != null) geigerTagGotView.setText(strEpc);
diff --git a/app/src/main/java/com/csl/cs108ademoapp/MainActivity.java b/app/src/main/java/com/csl/cs108ademoapp/MainActivity.java
index db01f08..71452b6 100644
--- a/app/src/main/java/com/csl/cs108ademoapp/MainActivity.java
+++ b/app/src/main/java/com/csl/cs108ademoapp/MainActivity.java
@@ -5,10 +5,8 @@
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.net.Uri;
-import android.nfc.NdefMessage;
-import android.nfc.NfcAdapter;
 import android.os.Handler;
-import android.os.Parcelable;
+
 import androidx.fragment.app.Fragment;
 import androidx.fragment.app.FragmentManager;
 import androidx.drawerlayout.widget.DrawerLayout;
@@ -16,8 +14,6 @@
 import androidx.appcompat.app.AppCompatActivity;
 import android.util.Log;
 import android.view.View;
-import android.view.inputmethod.InputMethodInfo;
-import android.view.inputmethod.InputMethodManager;
 import android.widget.AdapterView;
 import android.widget.ListView;
 import android.widget.TextView;
@@ -29,9 +25,6 @@
 import com.csl.cs108library4a.Cs108Library4A;
 import com.csl.cs108library4a.ReaderDevice;
 
-import java.io.UnsupportedEncodingException;
-import java.util.List;
-
 public class MainActivity extends AppCompatActivity {
     final boolean DEBUG = false; final String TAG = "Hello";
     public static boolean activityActive = false;
@@ -52,7 +45,6 @@ public class MainActivity extends AppCompatActivity {
     public static ReaderDevice tagSelected;
     Handler mHandler = new Handler();
 
-    public static NfcAdapter nfcAdapter = null;
     PendingIntent mPendingIntent;
     IntentFilter writeTagFilters[];
     String[][] techList;
@@ -85,28 +77,6 @@ protected void onCreate(Bundle savedInstanceState) {
         mCs108Library4a = new Cs108Library4A(mContext, mLogView);
         mSensorConnector = new SensorConnector(mContext);
 
-        InputMethodManager imeManager = (InputMethodManager) getApplicationContext().getSystemService(INPUT_METHOD_SERVICE);
-        List<InputMethodInfo> lst = imeManager.getInputMethodList();
-        for (InputMethodInfo info : lst) {
-//            MainActivity.mCs108Library4a.appendToLog(info.getId() + " " + info.loadLabel(getPackageManager()).toString());
-        }
-//        Intent intent = new Intent(MainActivity.this, CustomIME.class);
- //       startService(intent);
-//        savedInstanceState = null;
-
-        nfcAdapter = NfcAdapter.getDefaultAdapter(this);
-        if (nfcAdapter == null) MainActivity.mCs108Library4a.appendToLog("onNewIntent !!! This device doesn't support NFC");
-        else if (nfcAdapter.isEnabled() == false) MainActivity.mCs108Library4a.appendToLog("onNewIntent !!! This device doesn't enable NFC");
-        else {
-            readFromIntent(getIntent());
-
-            mPendingIntent = PendingIntent.getActivity(this, 0, new Intent(this, getClass()).addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP), 0);
-            IntentFilter tagDetected = new IntentFilter(NfcAdapter.ACTION_TAG_DISCOVERED);
-            tagDetected.addCategory(Intent.CATEGORY_DEFAULT);
-            writeTagFilters = new IntentFilter[] { tagDetected };
-            techList = new String[][]{{android.nfc.tech.Ndef.class.getName()}, {android.nfc.tech.NdefFormatable.class.getName()}};
-        }
-
         super.onCreate(savedInstanceState);
         if (savedInstanceState == null) selectItem(DrawerPositions.MAIN);
         Log.i(TAG, "MainActivity.onCreate.onCreate: END");
@@ -128,7 +98,6 @@ protected void onStart() {
     @Override
     protected void onResume() {
         super.onResume();
-        if (nfcAdapter != null && nfcAdapter.isEnabled()) nfcAdapter.enableForegroundDispatch(this, mPendingIntent, writeTagFilters, techList);
         activityActive = true; wedged = false;
         if (DEBUG) mCs108Library4a.appendToLog("MainActivity.onResume()");
     }
@@ -136,7 +105,6 @@ protected void onResume() {
     @Override
     protected void onPause() {
         if (DEBUG) mCs108Library4a.appendToLog("MainActivity.onPause()");
-        if (nfcAdapter != null) nfcAdapter.disableForegroundDispatch(this);
         activityActive = false;
         super.onPause();
     }
@@ -290,7 +258,9 @@ public void onBackPressed() {
     public static boolean permissionRequesting;
     @Override
     public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
-        MainActivity.mCs108Library4a.appendToLog("onRequestPermissionsResult ====");
+        MainActivity.mCs108Library4a.appendToLog("permissionRequesting: requestCode = " + requestCode + ", permissions is " + (permissions == null ? "null" : "valid") + ", grantResults is " + (grantResults == null ? "null" : "valid") );
+        MainActivity.mCs108Library4a.appendToLog("permissionRequesting: permissions[" + permissions.length + "] = " + (permissions != null && permissions.length > 0 ? permissions[0] : ""));
+        MainActivity.mCs108Library4a.appendToLog("permissionRequesting: grantResults[" + grantResults.length + "] = " + (grantResults != null && grantResults.length > 0 ? grantResults[0] : "") );
         super.onRequestPermissionsResult(requestCode, permissions, grantResults);
         permissionRequesting = false;
     }
@@ -414,58 +384,9 @@ protected void onNewIntent(Intent intent) {
         super.onNewIntent(intent);
         mCs108Library4a.appendToLog("onNewIntent !!! intent.getAction = " + intent.getAction());
         readFromIntent(intent);
-//        if (NfcAdapter.ACTION_NDEF_DISCOVERED.equals(intent.getAction())) {
-//        }
     }
     private void readFromIntent(Intent intent) {
         mCs108Library4a.appendToLog("onNewIntent !!! readFromIntent entry");
         String action = intent.getAction();
-        if (NfcAdapter.ACTION_TAG_DISCOVERED.equals(action)
-                || NfcAdapter.ACTION_TECH_DISCOVERED.equals(action)
-                || NfcAdapter.ACTION_NDEF_DISCOVERED.equals(action)) {
-            mCs108Library4a.appendToLog("onNewIntent !!! readFromIntent getAction = " + action);
-            Parcelable[] rawMsgs = intent.getParcelableArrayExtra(NfcAdapter.EXTRA_NDEF_MESSAGES);
-            mCs108Library4a.appendToLog("onNewIntent !!! readFromIntent rawMsgs.length = " + rawMsgs.length);
-            mCs108Library4a.appendToLog("onNewIntent !!! readFromIntent rawMsgs[0].toString = " + rawMsgs[0].toString());
-            NdefMessage[] msgs = null;
-            if (rawMsgs != null) {
-                msgs = new NdefMessage[rawMsgs.length];
-                for (int i = 0; i < rawMsgs.length; i++) {
-                    msgs[i] = (NdefMessage) rawMsgs[i];
-                }
-            }
-            buildTagViews(msgs);
-        }
-    }
-
-    private void buildTagViews(NdefMessage[] msgs) {
-        if (msgs == null || msgs.length == 0) return;
-        mCs108Library4a.appendToLog("onNewIntent !!! buildTagViews msgs.length = " + msgs.length + ", msgs[0].getRecords().size = " + msgs[0].getRecords().length);
-
-        String text = "";
-        for (int x = 0; x < msgs.length; x++) {
-        for (int y = 0; y < msgs[0].getRecords().length; y++) {
-            mCs108Library4a.appendToLog("onNewIntent !!! buildTagViews msgs[" + x + "][" + y + "].Inf = " + msgs[x].getRecords()[y].getTnf());
-            mCs108Library4a.appendToLog("onNewIntent !!! buildTagViews msgs[" + x + "][" + y + "].Type = " + mCs108Library4a.byteArrayToString(msgs[x].getRecords()[y].getType()));
-            mCs108Library4a.appendToLog("onNewIntent !!! buildTagViews msgs[" + x + "][" + y + "].Id = " + mCs108Library4a.byteArrayToString(msgs[x].getRecords()[y].getId()));
-            mCs108Library4a.appendToLog("onNewIntent !!! buildTagViews msgs[" + x + "][" + y + "].Payload = " + mCs108Library4a.byteArrayToString(msgs[x].getRecords()[y].getPayload()));
-            mCs108Library4a.appendToLog("onNewIntent !!! buildTagViews msgs[" + x + "][" + y + "].Class = " + msgs[x].getRecords()[y].getClass().toString());
-        }}
-
-        byte[] payload = msgs[0].getRecords()[0].getPayload();
-        mCs108Library4a.appendToLog("onNewIntent !!! buildTagViews payload.length = " + payload.length + ", with payload[0] = " + payload[0]);
-        mCs108Library4a.appendToLog("onNewIntent !!! buildTagViews payload = " + mCs108Library4a.byteArrayToString(payload));
-        String textEncoding = ((payload[0] & 128) == 0) ? "UTF-8" : "UTF-16"; // Get the Text Encoding
-        int languageCodeLength = payload[0] & 0063; // Get the Language Code, e.g. "en"
-        // String languageCode = new String(payload, 1, languageCodeLength, "US-ASCII");
-        try {
-            // Get the Text
-            text = new String(payload, languageCodeLength + 1, payload.length - languageCodeLength - 1, textEncoding);
-            mCs108Library4a.appendToLog("onNewIntent !!! buildTagViews text = " + text);
-        } catch (UnsupportedEncodingException e) {
-            mCs108Library4a.appendToLog("onNewIntent !!! buildTagViews UnsupportedEncoding" + e.toString());
-            Log.e("UnsupportedEncoding", e.toString());
-        }
-        //tvNFCContent.setText("NFC Content: " + text);
     }
 }
diff --git a/app/src/main/java/com/csl/cs108ademoapp/SaveList2ExternalTask.java b/app/src/main/java/com/csl/cs108ademoapp/SaveList2ExternalTask.java
index 46e7a9f..db4812c 100644
--- a/app/src/main/java/com/csl/cs108ademoapp/SaveList2ExternalTask.java
+++ b/app/src/main/java/com/csl/cs108ademoapp/SaveList2ExternalTask.java
@@ -11,8 +11,6 @@
 import android.os.Environment;
 import android.provider.Settings;
 
-import androidx.core.app.ActivityCompat;
-
 import com.csl.cs108library4a.Cs108Library4A;
 import com.csl.cs108library4a.ReaderDevice;
 
@@ -379,8 +377,11 @@ public String save2File(String messageStr, boolean requestPermission) {
             if (mContext.checkSelfPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
                 mCs108Library4a.appendToLog("WRITE_EXTERNAL_STORAGE Permission is required !!!");
                 writeExtPermission = false;
-                if (requestPermission) { MainActivity.permissionRequesting = true; requestPermissions((Activity) mContext, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1);
-                return null; }
+                if (requestPermission) {
+                    mCs108Library4a.appendToLog("requestPermissions WRITE_EXTERNAL_STORAGE 1");
+                    MainActivity.permissionRequesting = true; requestPermissions((Activity) mContext, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1);
+                    return null;
+                }
             } else mCs108Library4a.appendToLog("WRITE_EXTERNAL_STORAGE Permission is GRANTED !!!");
         }
 
diff --git a/app/src/main/java/com/csl/cs108ademoapp/adapters/FilterAdapter.java b/app/src/main/java/com/csl/cs108ademoapp/adapters/FilterAdapter.java
index 35a8fdb..13c7436 100644
--- a/app/src/main/java/com/csl/cs108ademoapp/adapters/FilterAdapter.java
+++ b/app/src/main/java/com/csl/cs108ademoapp/adapters/FilterAdapter.java
@@ -7,10 +7,11 @@
 
 import com.csl.cs108ademoapp.fragments.SettingFilterPostFragment;
 import com.csl.cs108ademoapp.fragments.SettingFilterPreFragment;
+import com.csl.cs108ademoapp.fragments.SettingFilterRssiFragment;
 
 public class FilterAdapter extends FragmentStatePagerAdapter {
-    private final int NO_OF_TABS = 2;
-    public Fragment fragment0, fragment1;
+    private final int NO_OF_TABS = 3;
+    public Fragment fragment0, fragment1, fragment2;
 
     @Override
     public Fragment getItem(int position) {
@@ -24,6 +25,10 @@ public Fragment getItem(int position) {
                 fragment = new SettingFilterPostFragment();
                 fragment1 = fragment;
                 break;
+            case 2:
+                fragment = new SettingFilterRssiFragment();
+                fragment2 = fragment;
+                break;
             default:
                 fragment = null;
                 break;
diff --git a/app/src/main/java/com/csl/cs108ademoapp/adapters/ReaderListAdapter.java b/app/src/main/java/com/csl/cs108ademoapp/adapters/ReaderListAdapter.java
index 078ba75..94915e6 100644
--- a/app/src/main/java/com/csl/cs108ademoapp/adapters/ReaderListAdapter.java
+++ b/app/src/main/java/com/csl/cs108ademoapp/adapters/ReaderListAdapter.java
@@ -86,7 +86,7 @@ public View getView(int position, View convertView, ViewGroup parent) {
             rssiTextView.setVisibility(View.VISIBLE);
             double rssiValue = reader.getRssi();
             if (MainActivity.mCs108Library4a.getRssiDisplaySetting() != 0 && rssiValue > 0)
-                rssiValue -= 106.98;
+                rssiValue -= MainActivity.mCs108Library4a.dBuV_dBm_constant;
             rssiTextView.setText(String.format("%.1f", rssiValue));
         }
 
diff --git a/app/src/main/java/com/csl/cs108ademoapp/fragments/AccessEm4325PassiveFragment.java b/app/src/main/java/com/csl/cs108ademoapp/fragments/AccessEm4325PassiveFragment.java
index 38305de..ab02d18 100644
--- a/app/src/main/java/com/csl/cs108ademoapp/fragments/AccessEm4325PassiveFragment.java
+++ b/app/src/main/java/com/csl/cs108ademoapp/fragments/AccessEm4325PassiveFragment.java
@@ -5,13 +5,8 @@
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
-import android.widget.AdapterView;
-import android.widget.ArrayAdapter;
 import android.widget.Button;
-import android.widget.CheckBox;
 import android.widget.EditText;
-import android.widget.LinearLayout;
-import android.widget.Spinner;
 import android.widget.TextView;
 import android.widget.Toast;
 
diff --git a/app/src/main/java/com/csl/cs108ademoapp/fragments/ConnectionFragment.java b/app/src/main/java/com/csl/cs108ademoapp/fragments/ConnectionFragment.java
index bc99563..d7f71fc 100644
--- a/app/src/main/java/com/csl/cs108ademoapp/fragments/ConnectionFragment.java
+++ b/app/src/main/java/com/csl/cs108ademoapp/fragments/ConnectionFragment.java
@@ -167,7 +167,6 @@ public void run() {
 
     private class DeviceScanTask extends AsyncTask<Void, String, String> {
         private long timeMillisUpdate = System.currentTimeMillis();
-        boolean usbDeviceFound = false;
         ArrayList<ReaderDevice> readersListOld = new ArrayList<ReaderDevice>();
         boolean wait4process = false; boolean scanning = false;
 
diff --git a/app/src/main/java/com/csl/cs108ademoapp/fragments/InventoryRfidSearchFragment.java b/app/src/main/java/com/csl/cs108ademoapp/fragments/InventoryRfidSearchFragment.java
index 815a0b2..60a0055 100644
--- a/app/src/main/java/com/csl/cs108ademoapp/fragments/InventoryRfidSearchFragment.java
+++ b/app/src/main/java/com/csl/cs108ademoapp/fragments/InventoryRfidSearchFragment.java
@@ -31,7 +31,7 @@
 import com.csl.cs108library4a.ReaderDevice;
 
 public class InventoryRfidSearchFragment extends CommonFragment {
-    final double dBuV_dBm_constant = 106.98;
+    double dBuV_dBm_constant = MainActivity.mCs108Library4a.dBuV_dBm_constant;
     final int labelMin = -90;
     final int labelMax = -10;
 
diff --git a/app/src/main/java/com/csl/cs108ademoapp/fragments/InventoryRfidiMultiFragment.java b/app/src/main/java/com/csl/cs108ademoapp/fragments/InventoryRfidiMultiFragment.java
index 45278f7..f3414c7 100644
--- a/app/src/main/java/com/csl/cs108ademoapp/fragments/InventoryRfidiMultiFragment.java
+++ b/app/src/main/java/com/csl/cs108ademoapp/fragments/InventoryRfidiMultiFragment.java
@@ -217,7 +217,7 @@ public void onItemClick(AdapterView<?> parent, View view, int position, long id)
         rfidRunTime = (TextView) getActivity().findViewById(R.id.inventoryRfidRunTime1);
         rfidVoltageLevel = (TextView) getActivity().findViewById(R.id.inventoryRfidVoltageLevel1);
         TextView rfidFilterOn = (TextView) getActivity().findViewById(R.id.inventoryRfidFilterOn1);
-        if (mDid != null || (MainActivity.mCs108Library4a.getSelectEnable() == false && MainActivity.mCs108Library4a.getInvMatchEnable() == false))
+        if (mDid != null || (MainActivity.mCs108Library4a.getSelectEnable() == false && MainActivity.mCs108Library4a.getInvMatchEnable() == false && MainActivity.mCs108Library4a.getRssiFilterEnable() == false))
             rfidFilterOn.setVisibility(View.INVISIBLE);
 
         rfidYieldView = (TextView) getActivity().findViewById(R.id.inventoryRfidYield1);
diff --git a/app/src/main/java/com/csl/cs108ademoapp/fragments/SettingAdminFragment.java b/app/src/main/java/com/csl/cs108ademoapp/fragments/SettingAdminFragment.java
index bf4da4b..7e2146d 100644
--- a/app/src/main/java/com/csl/cs108ademoapp/fragments/SettingAdminFragment.java
+++ b/app/src/main/java/com/csl/cs108ademoapp/fragments/SettingAdminFragment.java
@@ -1,6 +1,5 @@
 package com.csl.cs108ademoapp.fragments;
 
-import android.inputmethodservice.Keyboard;
 import android.os.Bundle;
 import android.os.Handler;
 import android.text.InputFilter;
diff --git a/app/src/main/java/com/csl/cs108ademoapp/fragments/SettingFilterFragment.java b/app/src/main/java/com/csl/cs108ademoapp/fragments/SettingFilterFragment.java
index 4c2ebd8..cc8bc88 100644
--- a/app/src/main/java/com/csl/cs108ademoapp/fragments/SettingFilterFragment.java
+++ b/app/src/main/java/com/csl/cs108ademoapp/fragments/SettingFilterFragment.java
@@ -18,7 +18,7 @@ public class SettingFilterFragment extends CommonFragment {
     private ViewPager viewPager;
     FilterAdapter mAdapter;
 
-    private String[] tabs = {"Pre-filter", "Post-filter"};
+    private String[] tabs = {"Pre-filter", "Post-filter", "Rssi-filter"};
 
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
diff --git a/app/src/main/java/com/csl/cs108ademoapp/fragments/SettingFilterRssiFragment.java b/app/src/main/java/com/csl/cs108ademoapp/fragments/SettingFilterRssiFragment.java
new file mode 100644
index 0000000..34cb547
--- /dev/null
+++ b/app/src/main/java/com/csl/cs108ademoapp/fragments/SettingFilterRssiFragment.java
@@ -0,0 +1,197 @@
+package com.csl.cs108ademoapp.fragments;
+
+import android.os.Bundle;
+import android.os.Handler;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.ArrayAdapter;
+import android.widget.Button;
+import android.widget.CheckBox;
+import android.widget.EditText;
+import android.widget.Spinner;
+import android.widget.TextView;
+import android.widget.Toast;
+
+import com.csl.cs108ademoapp.MainActivity;
+import com.csl.cs108ademoapp.R;
+import com.csl.cs108ademoapp.SettingTask;
+
+public class SettingFilterRssiFragment extends CommonFragment {
+    private CheckBox checkBoxEnable;
+    private Spinner spinnerFilterType, spinnerFilterOption;
+    private EditText editTextFilterThreshold1, editTextFilterThreshold2, editTextFilterCount;
+    private Button button;
+
+    final boolean sameCheck = false;
+    Handler mHandler = new Handler();
+
+    boolean invSelectEnable;
+    int invSelectFilterType = -1, invSelectFilterOption = -1;
+    double invSelectFilterThreshold1 = -1, invSelectFilterThreshold2 = -1;
+    long invSelectFilterCount = -1;
+
+    private SettingTask settingTask;
+
+    @Override
+    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
+        super.onCreateView(inflater, container, savedInstanceState, false);
+        return inflater.inflate(R.layout.fragment_filterrssi_content, container, false);
+    }
+
+    @Override
+    public void onActivityCreated(Bundle savedInstanceState) {
+        super.onActivityCreated(savedInstanceState);
+
+        checkBoxEnable = (CheckBox) getActivity().findViewById(R.id.filterRssiCheck);
+
+        spinnerFilterType = (Spinner) getActivity().findViewById(R.id.filterRssiFilterType);
+        ArrayAdapter<CharSequence> filterTypeAdapter = ArrayAdapter.createFromResource(getActivity(), R.array.filterType_options, R.layout.custom_spinner_layout);
+        filterTypeAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
+        spinnerFilterType.setAdapter(filterTypeAdapter);
+        spinnerFilterType.setEnabled(false);
+
+        spinnerFilterOption = (Spinner) getActivity().findViewById(R.id.filterRssiFilterOption);
+        ArrayAdapter<CharSequence> filterOptionAdapter = ArrayAdapter.createFromResource(getActivity(), R.array.filter_options1, R.layout.custom_spinner_layout);
+        filterOptionAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
+        spinnerFilterOption.setAdapter(filterOptionAdapter);
+
+        String strUnit = MainActivity.mCs108Library4a.getRssiDisplaySetting() > 0 ? "(dBm)" : "(dBuV)";
+        TextView textViewThreshold1 = (TextView) getActivity().findViewById(R.id.filterRssiThreshold1Label);
+        textViewThreshold1.setText(textViewThreshold1.getText().toString() + strUnit);
+        TextView textViewThreshold2 = (TextView) getActivity().findViewById(R.id.filterRssiThreshold2Label);
+        textViewThreshold2.setText(textViewThreshold2.getText().toString() + strUnit);
+
+        editTextFilterThreshold1 = (EditText) getActivity().findViewById(R.id.filterRssiThreshold1);
+        editTextFilterThreshold2 = (EditText) getActivity().findViewById(R.id.filterRssiThreshold2);
+        editTextFilterCount = (EditText) getActivity().findViewById(R.id.filterRssiCount);
+
+        button = (Button) getActivity().findViewById(R.id.filterRssiSaveButton);
+        button.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                boolean validValue = false;
+                if (MainActivity.mCs108Library4a.isBleConnected() == false) {
+                    Toast.makeText(MainActivity.mContext, R.string.toast_ble_not_connected, Toast.LENGTH_SHORT).show();
+                    return;
+                } else if (MainActivity.mCs108Library4a.isRfidFailure()) {
+                    Toast.makeText(MainActivity.mContext, "Rfid is disabled", Toast.LENGTH_SHORT).show();
+                    return;
+                } else {
+                    boolean bValid = false;
+                    try {
+                        invSelectEnable = checkBoxEnable.isChecked();
+                        invSelectFilterType = spinnerFilterType.getSelectedItemPosition();
+                        invSelectFilterOption = spinnerFilterOption.getSelectedItemPosition();
+                        invSelectFilterThreshold1 = Float.parseFloat(editTextFilterThreshold1.getText().toString());
+                        if (MainActivity.mCs108Library4a.getRssiDisplaySetting() > 0) invSelectFilterThreshold1 += MainActivity.mCs108Library4a.dBuV_dBm_constant;
+                        invSelectFilterThreshold2 = Float.parseFloat(editTextFilterThreshold2.getText().toString());
+                        if (MainActivity.mCs108Library4a.getRssiDisplaySetting() > 0) invSelectFilterThreshold2 += MainActivity.mCs108Library4a.dBuV_dBm_constant;
+                        invSelectFilterCount = Integer.parseInt(editTextFilterCount.getText().toString());
+                        bValid = true;
+                    } catch (Exception ex) {
+                        Toast.makeText(MainActivity.mContext, R.string.toast_invalid_range, Toast.LENGTH_SHORT).show();
+                    }
+                    if (bValid) settingUpdate();
+                }
+            }
+        });
+
+        if (sameCheck == false) MainActivity.mCs108Library4a.setSameCheck(false);
+        mHandler.post(updateRunnable);
+    }
+
+    @Override
+    public void onDestroy() {
+        if (settingTask != null) settingTask.cancel(true);
+        MainActivity.mCs108Library4a.setSameCheck(true);
+        mHandler.removeCallbacks(updateRunnable);
+        super.onDestroy();
+    }
+
+    public SettingFilterRssiFragment() {
+        super("SettingFilterRssiFragment");
+    }
+
+    private final Runnable updateRunnable = new Runnable() {
+        @Override
+        public void run() {
+            int iValue;
+            long lValue;
+            String updating = null;
+
+            if (MainActivity.mCs108Library4a.mrfidToWriteSize() != 0)   updating = "waiting empty buffer";
+            else {
+                if (updating == null) {
+                    boolean bValue = MainActivity.mCs108Library4a.getRssiFilterEnable();
+                    MainActivity.mCs108Library4a.appendToLog("updateRunnable getSelectEnable = " + bValue);
+                    checkBoxEnable.setChecked(bValue);
+                }
+                if (updating == null) {
+                    int iValue1 = MainActivity.mCs108Library4a.getRssiFilterType();
+                    MainActivity.mCs108Library4a.appendToLog("updateRunnable getSelectAction = " + iValue1);
+                    if (iValue1 < 0) updating = "getting filter type";
+                    else spinnerFilterType.setSelection(iValue1);
+                }
+                if (updating == null) {
+                    int iValue1 = MainActivity.mCs108Library4a.getRssiFilterOption();
+                    MainActivity.mCs108Library4a.appendToLog("updateRunnable getSelectAction = " + iValue1);
+                    if (iValue1 < 0) updating = "getting filter option";
+                    else spinnerFilterOption.setSelection(iValue1);
+                }
+                if (updating == null) {
+                    double dValue = MainActivity.mCs108Library4a.getRssiFilterThreshold1();
+                    if (dValue < 0) updating = "updating threshold 1";
+                    else editTextFilterThreshold1.setText(String.format("%.1f", (MainActivity.mCs108Library4a.getRssiDisplaySetting() > 0 ? dValue -= MainActivity.mCs108Library4a.dBuV_dBm_constant : dValue)));
+                }
+                if (updating == null) {
+                    double dValue = MainActivity.mCs108Library4a.getRssiFilterThreshold2();
+                    if (dValue < 0) updating = "updating threshold 2";
+                    else editTextFilterThreshold2.setText(String.format("%.1f", (MainActivity.mCs108Library4a.getRssiDisplaySetting() > 0 ? dValue -= MainActivity.mCs108Library4a.dBuV_dBm_constant : dValue)));
+                }
+                if (updating == null) {
+                    long lValue1 = MainActivity.mCs108Library4a.getRssiFilterCount();
+                    if (lValue1 < 0) updating = "updating count";
+                    else editTextFilterCount.setText(String.valueOf(lValue1));
+                }
+            }
+            if (updating != null) {
+                mHandler.postDelayed(updateRunnable, 1000);
+                MainActivity.mCs108Library4a.appendToLog("Updating in " + updating);
+            }
+        }
+    };
+
+    void settingUpdate() {
+        boolean sameSetting = true;
+        String invalidRequest = null;
+
+        if (sameSetting == true && invalidRequest == null) {
+            if (MainActivity.mCs108Library4a.getRssiFilterEnable() != invSelectEnable
+                    || MainActivity.mCs108Library4a.getRssiFilterType() != invSelectFilterType
+                    || MainActivity.mCs108Library4a.getRssiFilterOption() != invSelectFilterOption) {
+                sameSetting = false;
+                if (MainActivity.mCs108Library4a.setRssiFilterConfig(invSelectEnable, invSelectFilterType, invSelectFilterOption) == false) invalidRequest = "setting filter type";
+            }
+            if (MainActivity.mCs108Library4a.getRssiFilterThreshold1() != invSelectFilterThreshold1 || MainActivity.mCs108Library4a.getRssiFilterThreshold2() != invSelectFilterThreshold2) {
+                sameSetting = false;
+                if (MainActivity.mCs108Library4a.setRssiFilterThreshold(invSelectFilterThreshold1, invSelectFilterThreshold2) == false) invalidRequest = "setting filter threshold";
+            }
+            if (MainActivity.mCs108Library4a.getRssiFilterCount() != invSelectFilterCount) {
+                sameSetting = false;
+                MainActivity.mCs108Library4a.appendToLog("rssiFilterCount = " + invSelectFilterCount);
+                if (MainActivity.mCs108Library4a.setRssiFilterCount(invSelectFilterCount) == false) invalidRequest = "setting filter count";
+            }
+        }
+
+        if (invalidRequest != null) {
+            String strValue = "Invalid " + invalidRequest + ". Operation is cancelled.";
+            Toast.makeText(MainActivity.mContext, strValue, Toast.LENGTH_SHORT).show();
+
+        } else {
+            settingTask = new SettingTask(button, sameSetting, false);
+            settingTask.execute();
+            MainActivity.mCs108Library4a.saveSetting2File();
+        }
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/res/layout/fragment_filterrssi_content.xml b/app/src/main/res/layout/fragment_filterrssi_content.xml
new file mode 100644
index 0000000..b4d3d35
--- /dev/null
+++ b/app/src/main/res/layout/fragment_filterrssi_content.xml
@@ -0,0 +1,150 @@
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    style="@style/base_layout_style"
+    android:paddingLeft="0dp"
+    android:paddingRight="0dp"
+    android:orientation="vertical">
+
+    <TableRow
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="@dimen/default_top_margin"
+        android:paddingLeft="10dp">
+
+        <TextView
+            android:layout_width="0dp"
+            android:layout_weight="1"
+            style="@style/style_normal_font"
+            android:text="Filter type" />
+
+        <Spinner
+            android:id="@+id/filterRssiFilterType"
+            android:layout_width="0dp"
+            android:layout_weight="2"
+            android:background="@drawable/my_edittext_background"
+            style="@style/style_default_spinner" />
+    </TableRow>
+
+    <TableRow
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:paddingLeft="10dp">
+
+        <TextView
+            android:layout_width="0dp"
+            android:layout_weight="1"
+            style="@style/style_normal_font"
+            android:text="Filter option" />
+
+        <Spinner
+            android:id="@+id/filterRssiFilterOption"
+            android:layout_width="0dp"
+            android:layout_weight="3"
+            android:background="@drawable/my_edittext_background"
+            style="@style/style_default_spinner" />
+    </TableRow>
+
+    <TableRow
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="@dimen/default_top_margin"
+        android:paddingLeft="10dp">
+
+        <TextView
+            android:id="@+id/filterRssiThreshold1Label"
+            android:layout_width="0dp"
+            android:layout_weight="1"
+            android:layout_marginTop="5dp"
+            android:gravity="left"
+            style="@style/style_normal_font"
+            android:text="Filter threshold 1" />
+
+        <EditText
+            android:id="@+id/filterRssiThreshold1"
+            android:layout_width="0dp"
+            android:layout_weight="1"
+            android:gravity="center"
+            android:inputType="numberDecimal|numberSigned"
+            style="@style/style_normal_font" />
+    </TableRow>
+
+    <TableRow
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="@dimen/default_top_margin"
+        android:paddingLeft="10dp"
+        android:visibility="gone">
+
+        <TextView
+            android:id="@+id/filterRssiThreshold2Label"
+            android:layout_width="0dp"
+            android:layout_weight="1"
+            android:layout_marginTop="5dp"
+            android:gravity="left"
+            style="@style/style_normal_font"
+            android:text="Filter threshold 2" />
+
+        <EditText
+            android:id="@+id/filterRssiThreshold2"
+            android:layout_width="0dp"
+            android:layout_weight="1"
+            android:gravity="center"
+            android:inputType="numberDecimal|numberSigned"
+            style="@style/style_normal_font" />
+    </TableRow>
+
+    <TableRow
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="@dimen/default_top_margin"
+        android:paddingLeft="10dp"
+        android:visibility="gone">
+
+        <TextView
+            android:layout_width="0dp"
+            android:layout_weight="1"
+            android:layout_marginTop="5dp"
+            android:gravity="left"
+            style="@style/style_normal_font"
+            android:text="Filter count" />
+
+        <EditText
+            android:id="@+id/filterRssiCount"
+            android:layout_width="0dp"
+            android:layout_weight="1"
+            android:gravity="center"
+            android:inputType="numberDecimal"
+            style="@style/style_normal_font" />
+    </TableRow>
+
+    <TableRow
+        android:layout_width="match_parent"
+        android:layout_height="0dp"
+        android:layout_weight="25"
+        android:layout_marginTop="@dimen/default_top_margin"
+        android:paddingLeft="10dp">
+
+        <TextView
+            android:layout_width="0dp"
+            android:layout_weight="1"
+            android:layout_marginTop="5dp"
+            android:gravity="left"
+            style="@style/style_normal_font"
+            android:text="@string/enable_filter" />
+
+        <CheckBox
+            android:id="@+id/filterRssiCheck"
+            android:layout_width="0dp"
+            android:layout_weight="1"
+            android:text="" />
+    </TableRow>
+
+    <Button
+        android:id="@+id/filterRssiSaveButton"
+        android:layout_width="match_parent"
+        android:layout_height="50dp"
+        android:gravity="center"
+        style="@style/style_button_font"
+        android:text="@string/save_title" />
+
+</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 878b280..7822ba6 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -88,6 +88,24 @@
         <item>Bit</item>
     </string-array>
 
+    <string-array name="filterType_options">
+        <item>NB_RSSI value filtering</item>
+        <item>RSSI value filtering</item>
+    </string-array>
+
+    <string-array name="filter_options">
+        <item>NB_RSSI/RSSI "&lt;"= threshold 1</item>
+        <item>NB_RSSI/RSSI >= threshold 1</item>
+        <item>NB_RSSI/RSSI == threshold 1</item>
+        <item>NB_RSSI/RSSI "&lt;"= threshold 2 and >= threshold 1</item>
+        <item>NB_RSSI/RSSI "&lt;"= threshold 1 and >= threshold 2</item>
+    </string-array>
+
+    <string-array name="filter_options1">
+        <item>NB_RSSI/RSSI "&lt;"= threshold 1</item>
+        <item>NB_RSSI/RSSI >= threshold 1</item>
+    </string-array>
+
     <string-array name="write_memoryBank_options">
         <item>EPC</item>
         <item>User</item>
diff --git a/cs108library4a/build.gradle b/cs108library4a/build.gradle
index ec928b1..bf733a0 100644
--- a/cs108library4a/build.gradle
+++ b/cs108library4a/build.gradle
@@ -1,13 +1,13 @@
 apply plugin: 'com.android.library'
 
 android {
-    compileSdkVersion 30
+    compileSdkVersion 31
     defaultConfig {
         minSdkVersion 19
-        targetSdkVersion 30
+        targetSdkVersion 31
         versionCode 34
-        versionName "2.3.0"
-        buildConfigField 'String', 'VERSION_NAME', "\"2.3.0\""
+        versionName "2.3.4"
+        buildConfigField 'String', 'VERSION_NAME', "\"2.3.4\""
 
         testInstrumentationRunner 'androidx.test.runner.AndroidJUnitRunner'
     }
diff --git a/cs108library4a/src/main/AndroidManifest.xml b/cs108library4a/src/main/AndroidManifest.xml
index 354d4ce..be3fde8 100644
--- a/cs108library4a/src/main/AndroidManifest.xml
+++ b/cs108library4a/src/main/AndroidManifest.xml
@@ -2,11 +2,11 @@
     package="com.csl.cs108library4a">
 
     <uses-feature android:name="android.hardware.bluetooth_le" />
-    <uses-feature android:name="android.hardware.usb.host" android:required="false" />
 
-    <uses-permission android:name="android.permission.USB_PERMISSION" />
     <uses-permission android:name="android.permission.BLUETOOTH" />
     <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
+    <uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
+    <uses-permission android:name="android.permission.BLUETOOTH_SCAN" />
     <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
     <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
     <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
diff --git a/cs108library4a/src/main/java/com/csl/cs108library4a/BleConnector.java b/cs108library4a/src/main/java/com/csl/cs108library4a/BleConnector.java
index b92e36b..eb5c18e 100644
--- a/cs108library4a/src/main/java/com/csl/cs108library4a/BleConnector.java
+++ b/cs108library4a/src/main/java/com/csl/cs108library4a/BleConnector.java
@@ -125,6 +125,7 @@ public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState
             switch (newState) {
                 case BluetoothProfile.STATE_DISCONNECTED:
                     if (DEBUG) appendToLog("abcc state=Disconnected with status = " + status);
+                    if (disconnectRunning == false) disconnect();
                     break;
 
                 case BluetoothProfile.STATE_CONNECTED:
@@ -358,7 +359,7 @@ boolean writeBleStreamOut(byte[] value) {
             if (bValue == false) writeBleFailure++;
             else {
                 writeBleFailure = 0;
-                if (DEBUG_BTDATA0) appendToLog(byteArrayToString(value));
+                if (DEBUG_BTDATA0) appendToLog("BtData: " + byteArrayToString(value));
                 _writeCharacteristic_in_progress = true;
                 mStreamWriteCountOld = mStreamWriteCount;
                 mStreamWriteCount += value.length;
@@ -412,7 +413,7 @@ public void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteris
                     streamInBytesMissing += v.length;
                 } else {
                     utility.writeDebug2File("A, " + System.currentTimeMillis());
-                    if (DEBUG_BTDATA0) Log.i(TAG, ".Hello: StreamIn = " + byteArrayToString(v));
+                    if (DEBUG_BTDATA0) Log.i(TAG, ".Hello: BtData = " + byteArrayToString(v));
                     if (isStreamInBufferRing) {
                         streamInBufferPush(v, 0, v.length);
                     } else {
@@ -538,6 +539,10 @@ boolean scanLeDevice(boolean enable, BluetoothAdapter.LeScanCallback mLeScanCall
         if (enable && Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
             appendToLog("Checking permission and grant !!!");
             LocationManager locationManager = (LocationManager) mContext.getSystemService(LOCATION_SERVICE);
+            appendToLog("locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER) = " + locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER));
+            appendToLog("locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER) = " + locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER));
+            appendToLog("ActivityCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_FINE_LOCATION) = " + ActivityCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_FINE_LOCATION));
+            appendToLog("ActivityCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_COARSE_LOCATION)  = " + ActivityCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_COARSE_LOCATION));
             if (false && locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER) == false && locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER) == false) {
                 boolean isShowing = false;
                 if (popupWindow != null) isShowing = popupWindow.isShowing();
@@ -569,8 +574,10 @@ public void onClick(View v) {
                     bAlerting = true;
                     popupAlert();
                     return false;
-                } else
-                requestPermissions(activity, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 123);
+                } else {
+                    appendToLog("requestPermissions ACCESS_FINE_LOCATION 123");
+                    requestPermissions(activity, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 123);
+                }
             }
         }
 
@@ -606,8 +613,12 @@ public void onClick(View v) {
                 mScanning = false; result = true;
             } else {
                 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
-                    if (DEBUG) appendToLog("scanLeDevice(" + enable + "): START with mleScanner");
-                    mleScanner.startScan(mScanCallBack);
+                    if (DEBUG) appendToLog("scanLeDevice(" + enable + "): START with mleScanner. ActivityCompat.checkSelfPermission(activity, Manifest.permission.BLUETOOTH_SCAN) = " + ActivityCompat.checkSelfPermission(mContext, Manifest.permission.BLUETOOTH_SCAN));
+                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S && ActivityCompat.checkSelfPermission(mContext, Manifest.permission.BLUETOOTH_SCAN) != PackageManager.PERMISSION_GRANTED) {
+                        appendToLog("requestPermissions BLUETOOTH_SCAN 123");
+                        requestPermissions(activity, new String[]{Manifest.permission.BLUETOOTH_SCAN}, 123);
+                        return false;
+                    } else mleScanner.startScan(mScanCallBack);
                 } else {
                     if (DEBUG) appendToLog("scanLeDevice(" + enable + "): START with mBluetoothAdapter");
                     mBluetoothAdapter.startLeScan(mLeScanCallback);
@@ -636,7 +647,7 @@ public void run() {
                         isLocationAccepted = true;
                         appendToLog("StreamOut: This from FALSE proc");
                         if (ActivityCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(activity, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
-                            appendToLog("StreamOut: request ACCESS_FINE_LOCATION");
+                            appendToLog("requestPermissions ACCESS_FINE_LOCATION 123");
                             requestPermissions(activity, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 123);
                         }
                         {
diff --git a/cs108library4a/src/main/java/com/csl/cs108library4a/Cs108Connector.java b/cs108library4a/src/main/java/com/csl/cs108library4a/Cs108Connector.java
index ecf98e8..8cccf22 100644
--- a/cs108library4a/src/main/java/com/csl/cs108library4a/Cs108Connector.java
+++ b/cs108library4a/src/main/java/com/csl/cs108library4a/Cs108Connector.java
@@ -377,15 +377,10 @@ void cs108ConnectorDataInit() {
         mBluetoothConnector = new BluetoothConnector(context, mLogView);
     }
 
-    private enum CS108Connection {
-        BLUETOOTH, USB, OTHER
-    }
-
     enum Cs108ConnectedDevices {
         RFID, BARCODE, NOTIFICATION, SILICON_LAB, BLUETOOTH, OTHER
     }
     class Cs108ReadData {
-        CS108Connection cs108Connection;
         Cs108ConnectedDevices cs108ConnectedDevices;
         byte[] dataValues;
         boolean invalidSequence;
@@ -401,7 +396,6 @@ class Cs108ReadData {
     Context context; TextView mLogView;
     Cs108Connector(Context context, TextView mLogView) {
         super(context, mLogView);
-//        mUsbConnector = new UsbConnector(context, mLogView, 33896, 4292);
 
         this.context = context;
         this.mLogView = mLogView;
@@ -626,7 +620,7 @@ class RfidDevice {
 
         boolean inventoring = false;
         boolean isInventoring() { return  inventoring; }
-        void setInventoring(boolean enable) { inventoring = enable; debugFileEnable(enable); }
+        void setInventoring(boolean enable) { inventoring = enable; debugFileEnable(false); }
 
         RfidReaderChip mRfidReaderChip = new RfidReaderChip();
 
@@ -1630,7 +1624,7 @@ enum HostRegRequests {
         //HST_OEM_ADDR, HST_OEM_DATA,
         HST_ANT_CYCLES, HST_ANT_DESC_SEL, HST_ANT_DESC_CFG, MAC_ANT_DESC_STAT, HST_ANT_DESC_PORTDEF, HST_ANT_DESC_DWELL, HST_ANT_DESC_RFPOWER, HST_ANT_DESC_INV_CNT,
         HST_TAGMSK_DESC_SEL, HST_TAGMSK_DESC_CFG, HST_TAGMSK_BANK, HST_TAGMSK_PTR, HST_TAGMSK_LEN, HST_TAGMSK_0_3,
-        HST_QUERY_CFG, HST_INV_CFG, HST_INV_SEL, HST_INV_ALG_PARM_0, HST_INV_ALG_PARM_1, HST_INV_ALG_PARM_2, HST_INV_ALG_PARM_3, HST_INV_EPC_MATCH_CFG, HST_INV_EPCDAT_0_3,
+        HST_QUERY_CFG, HST_INV_CFG, HST_INV_SEL, HST_INV_ALG_PARM_0, HST_INV_ALG_PARM_1, HST_INV_ALG_PARM_2, HST_INV_ALG_PARM_3, HST_INV_RSSI_FILTERING_CONFIG, HST_INV_RSSI_FILTERING_THRESHOLD, HST_INV_RSSI_FILTERING_COUNT, HST_INV_EPC_MATCH_CFG, HST_INV_EPCDAT_0_3,
         HST_TAGACC_DESC_CFG, HST_TAGACC_BANK, HST_TAGACC_PTR, HST_TAGACC_CNT, HST_TAGACC_LOCKCFG, HST_TAGACC_ACCPWD, HST_TAGACC_KILLPWD, HST_TAGWRDAT_SEL, HST_TAGWRDAT_0,
         HST_RFTC_CURRENT_PROFILE,
         HST_RFTC_FRQCH_SEL, HST_RFTC_FRQCH_CFG, HST_RFTC_FRQCH_DESC_PLLDIVMULT, HST_RFTC_FRQCH_DESC_PLLDACCTL, HST_RFTC_FRQCH_CMDSTART,
@@ -1730,6 +1724,12 @@ class Rx000Setting {
             }
 
             if (set_default_setting) {
+                rssiFilterType = mDefault.rssiFilterType;
+                rssiFilterOption = mDefault.rssiFilterOption;
+                rssiFilterThreshold1 = mDefault.rssiFilterThreshold;
+                rssiFilterThreshold2 = mDefault.rssiFilterThreshold;
+                rssiFilterCount = mDefault.rssiFilterCount;
+
                 matchEnable = mDefault.matchEnable;
                 matchType = mDefault.matchType;
                 matchLength = mDefault.matchLength;
@@ -1790,6 +1790,11 @@ class Rx000Setting_default {
             int brandid = 0;
             int algoSelect = 3;
 
+            int rssiFilterType = 0;
+            int rssiFilterOption = 0;
+            int rssiFilterThreshold = 0;
+            long rssiFilterCount = 0;
+
             int matchEnable = 0;
             int matchType = 0;
             int matchLength = 0;
@@ -2788,6 +2793,101 @@ boolean setAlgoRunTilZero(int algoRunTilZero) {
             return algoSelectedData[algoSelect].setAlgoRunTilZero(algoRunTilZero);
         }
 
+        int rssiFilterConfig = -1;
+        final int RSSIFILTERTYPE_INVALID = -1, RSSIFILTERTYPE_MIN = 0, RSSIFILTERTYPE_MAX = 2;
+        int rssiFilterType = RSSIFILTERTYPE_INVALID;
+        final int RSSIFILTEROPTION_INVALID = -1, RSSIFILTEROPTION_MIN = 0, RSSIFILTEROPTION_MAX = 4;
+        int rssiFilterOption = RSSIFILTEROPTION_INVALID;
+        int getRssiFilterType() {
+            if (rssiFilterType < 0) getHST_INV_RSSI_FILTERING_CONFIG();
+            return rssiFilterType;
+        }
+        int getRssiFilterOption() {
+            if (rssiFilterOption < 0) getHST_INV_RSSI_FILTERING_CONFIG();
+            return rssiFilterOption;
+        }
+        private boolean getHST_INV_RSSI_FILTERING_CONFIG() {
+            byte[] msgBuffer = new byte[]{(byte) 0x70, 0, 7, 9, 0, 0, 0, 0};
+            return mRfidDevice.mRfidReaderChip.sendHostRegRequest(HostRegRequests.HST_INV_RSSI_FILTERING_CONFIG, false, msgBuffer);
+        }
+        boolean setHST_INV_RSSI_FILTERING_CONFIG(int rssiFilterType, int rssiFilterOption) {
+            byte[] msgBuffer = new byte[]{(byte) 0x70, 1, 7, 9, 0, 0, 0, 0};
+            if (rssiFilterType < RSSIFILTERTYPE_MIN || rssiFilterType > RSSIFILTERTYPE_MAX)
+                rssiFilterType = mDefault.rssiFilterType;
+            if (rssiFilterOption < RSSIFILTEROPTION_MIN || matchType > RSSIFILTEROPTION_MAX)
+                rssiFilterOption = mDefault.rssiFilterOption;
+            if (this.rssiFilterType == rssiFilterType && this.rssiFilterOption == rssiFilterOption && sameCheck) return true;
+            msgBuffer[4] |= (byte) (rssiFilterType & 0xF);
+            msgBuffer[4] |= (byte) ((rssiFilterOption & 0xF) << 4);
+            this.rssiFilterType = rssiFilterType;
+            this.rssiFilterOption = rssiFilterOption;
+            boolean bValue = mRfidDevice.mRfidReaderChip.sendHostRegRequest(HostRegRequests.HST_INV_RSSI_FILTERING_CONFIG, true, msgBuffer);
+            if (false) getHST_INV_RSSI_FILTERING_CONFIG();
+            return bValue;
+        }
+
+        final int RSSIFILTERTHRESHOLD_INVALID = -1, RSSIFILTERTHRESHOLD_MIN = 0, RSSIFILTERTHRESHOLD_MAX = 0xFFFF;
+        int rssiFilterThreshold1 = RSSIFILTERTHRESHOLD_INVALID;
+        int getRssiFilterThreshold1() {
+            if (rssiFilterThreshold1 < 0) getHST_INV_RSSI_FILTERING_THRESHOLD();
+            return rssiFilterThreshold1;
+        }
+        int rssiFilterThreshold2 = RSSIFILTERTHRESHOLD_INVALID;
+        int getRssiFilterThreshold2() {
+            if (rssiFilterThreshold2 < 0) getHST_INV_RSSI_FILTERING_THRESHOLD();
+            return rssiFilterThreshold2;
+        }
+        private boolean getHST_INV_RSSI_FILTERING_THRESHOLD() {
+            byte[] msgBuffer = new byte[]{(byte) 0x70, 0, 8, 9, 0, 0, 0, 0};
+            return mRfidDevice.mRfidReaderChip.sendHostRegRequest(HostRegRequests.HST_INV_RSSI_FILTERING_THRESHOLD, false, msgBuffer);
+        }
+        boolean setHST_INV_RSSI_FILTERING_THRESHOLD(int rssiFilterThreshold1, int rssiFilterThreshold2) {
+            byte[] msgBuffer = new byte[]{(byte) 0x70, 1, 8, 9, 0, 0, 0, 0};
+            if (rssiFilterThreshold1 < RSSIFILTERTHRESHOLD_MIN || rssiFilterThreshold1 > RSSIFILTERTHRESHOLD_MAX)
+                rssiFilterThreshold1 = mDefault.rssiFilterThreshold;
+            if (rssiFilterThreshold2 < RSSIFILTERTHRESHOLD_MIN || rssiFilterThreshold2 > RSSIFILTERTHRESHOLD_MAX)
+                rssiFilterThreshold2 = mDefault.rssiFilterThreshold;
+            if (this.rssiFilterThreshold1 == rssiFilterThreshold1 && this.rssiFilterThreshold2 == rssiFilterThreshold2 && sameCheck) return true;
+            msgBuffer[4] |= (byte) (rssiFilterThreshold1 & 0xFF);
+            msgBuffer[5] |= (byte) ((rssiFilterThreshold1 >> 8) & 0xFF);
+            msgBuffer[6] |= (byte) (rssiFilterThreshold2 & 0xFF);
+            msgBuffer[7] |= (byte) ((rssiFilterThreshold2 >> 8) & 0xFF);
+            this.rssiFilterThreshold1 = rssiFilterThreshold1;
+            this.rssiFilterThreshold2 = rssiFilterThreshold2;
+            boolean bValue = mRfidDevice.mRfidReaderChip.sendHostRegRequest(HostRegRequests.HST_INV_RSSI_FILTERING_THRESHOLD, true, msgBuffer);
+            if (false) getHST_INV_RSSI_FILTERING_THRESHOLD();
+            return bValue;
+        }
+
+        final long RSSIFILTERCOUNT_INVALID = -1, RSSIFILTERCOUNT_MIN = 0, RSSIFILTERCOUNT_MAX = 1000000;
+        long rssiFilterCount = RSSIFILTERCOUNT_INVALID;
+        long getRssiFilterCount() {
+            if (rssiFilterCount < 0) getHST_INV_RSSI_FILTERING_COUNT();
+            return rssiFilterCount;
+        }
+        private boolean getHST_INV_RSSI_FILTERING_COUNT() {
+            byte[] msgBuffer = new byte[]{(byte) 0x70, 0, 9, 9, 0, 0, 0, 0};
+            return mRfidDevice.mRfidReaderChip.sendHostRegRequest(HostRegRequests.HST_INV_RSSI_FILTERING_THRESHOLD, false, msgBuffer);
+        }
+        boolean setHST_INV_RSSI_FILTERING_COUNT(long rssiFilterCount) {
+            appendToLog("entry: rssiFilterCount = " + rssiFilterCount + ", this.rssiFilterCount = " + this.rssiFilterCount);
+            byte[] msgBuffer = new byte[]{(byte) 0x70, 1, 9, 9, 0, 0, 0, 0};
+            if (rssiFilterCount < RSSIFILTERCOUNT_MIN || rssiFilterCount > RSSIFILTERCOUNT_MAX)
+                rssiFilterCount = mDefault.rssiFilterCount;
+            appendToLog("rssiFilterCount 1 = " + rssiFilterCount + ", this.rssiFilterCount = " + this.rssiFilterCount);
+            if (this.rssiFilterCount == rssiFilterCount && sameCheck) return true;
+            appendToLog("rssiFilterCount 2 = " + rssiFilterCount + ", this.rssiFilterCount = " + this.rssiFilterCount);
+            msgBuffer[4] |= (byte) (rssiFilterCount & 0xFF);
+            msgBuffer[5] |= (byte) ((rssiFilterCount >> 8) & 0xFF);
+            msgBuffer[6] |= (byte) ((rssiFilterCount >> 16) & 0xFF);
+            msgBuffer[7] |= (byte) ((rssiFilterCount >> 24) & 0xFF);
+            this.rssiFilterCount = rssiFilterCount;
+            appendToLog("entering to sendHostRegRequest: rssiFilterCount = " + rssiFilterCount);
+            boolean bValue = mRfidDevice.mRfidReaderChip.sendHostRegRequest(HostRegRequests.HST_INV_RSSI_FILTERING_COUNT, true, msgBuffer);
+            appendToLog("after sendHostRegRequest: rssiFilterCount = " + rssiFilterCount);
+            return bValue;
+        }
+
         final int MATCHENABLE_INVALID = -1; final int MATCHENABLE_MIN = 0; final int MATCHENABLE_MAX = 1;
         int matchEnable = MATCHENABLE_INVALID;
         int getInvMatchEnable() {
@@ -4330,14 +4430,30 @@ public class RfidReaderChip {
         private boolean clearTempDataIn_request = false;
         boolean commandOperating;
 
-        double decodeWideBandRSSI(byte byteRSSI) {
+        double decodeNarrowBandRSSI(byte byteRSSI) {
             byte mantissa = byteRSSI;
             mantissa &= 0x07;
             byte exponent = byteRSSI;
             exponent >>= 3;
             double dValue = 20 * log10(pow(2, exponent) * (1 + (mantissa / pow(2, 3))));
+            if (false) appendToLog("byteRSSI = " + String.format("%X", byteRSSI) + ", mantissa = " + mantissa + ", exponent = " + exponent + "dValue = " + dValue);
             return dValue;
         }
+        int encodeNarrowBandRSSI(double dRSSI) {
+            double dValue = dRSSI / 20;
+            dValue = pow(10, dValue);
+            int exponent = 0;
+            if (false) appendToLog("exponent = " + exponent + ", dValue = " + dValue);
+            while ((dValue + 0.5) >= 2) {
+                dValue /= 2; exponent++;
+                if (false) appendToLog("exponent = " + exponent + ", dValue = " + dValue);
+            }
+            dValue--;
+            int mantissa = (int)((dValue * 8) + 0.5);
+            int iValue = ((exponent & 0x1F) << 3) | (mantissa & 0x7);
+            if (false) appendToLog("dRssi = " + dRSSI + ", exponent = " + exponent + ", mantissa = " + mantissa + ", iValue = " + String.format("%X", iValue));
+            return iValue;
+        }
 
         long firmware_ontime_ms = 0; long date_time_ms = 0; boolean bRx000ToReading = false;
         void mRx000UplinkHandler() {
@@ -4739,6 +4855,22 @@ else if ((mRfidToReading[startIndex + 0] == (byte) 0x00 || mRfidToReading[startI
                                                     }
                                                     break;
                                                 }
+                                                case 0x0907:
+                                                    mRx000Setting.rssiFilterType = dataIn[startIndex + 4] & 0xF;
+                                                    mRx000Setting.rssiFilterOption = (dataIn[startIndex + 4] >> 4) & 0xF;
+                                                    break;
+                                                case 0x0908:
+                                                    mRx000Setting.rssiFilterThreshold1 = dataIn[startIndex + 4];
+                                                    mRx000Setting.rssiFilterThreshold1 += (dataIn[startIndex + 5] << 8);
+                                                    mRx000Setting.rssiFilterThreshold2 = dataIn[startIndex + 6];
+                                                    mRx000Setting.rssiFilterThreshold2 += (dataIn[startIndex + 7] << 8);
+                                                    break;
+                                                case 0x0909:
+                                                    mRx000Setting.rssiFilterCount = dataIn[startIndex + 4];
+                                                    mRx000Setting.rssiFilterCount += (dataIn[startIndex + 5] << 8);
+                                                    mRx000Setting.rssiFilterCount += (dataIn[startIndex + 6] << 16);
+                                                    mRx000Setting.rssiFilterCount += (dataIn[startIndex + 7] << 24);
+                                                    break;
                                                 case 0x0911:
                                                     mRx000Setting.matchEnable = dataIn[startIndex + 4] & 0x01;
                                                     mRx000Setting.matchType = ((dataIn[startIndex + 4] & 0x02) >> 1);
@@ -4983,7 +5115,6 @@ else if ((mRfidToReading[startIndex + 0] == (byte) 0x00 || mRfidToReading[startI
                                                             date_time_ms = date_time;
                                                             if (true)
                                                                 appendToLog("command COMMAND_BEGIN is found with packageLength=" + packageLengthRead + ", with firmware count=" + lValue + ", date_time=" + date_time + ", expected firmware count=" + expected_firmware_ontime_ms);
-                                                            //if (mUsbConnector != null) mUsbConnector.inventorRunning = true;
                                                         }
                                                     }
                                                 }
@@ -5036,17 +5167,7 @@ else if ((mRfidToReading[startIndex + 0] == (byte) 0x00 || mRfidToReading[startI
                                                                     time1 = time1 = time1 << 8;
                                                                     time1 |= dataA.dataValues[0] & 0x00FF;
                                                                     dataA.decodedTime = time1;
-
-                                                                    if (true)
-                                                                        dataA.decodedRssi = decodeWideBandRSSI(dataA.dataValues[13 - 8]);
-                                                                    else {
-                                                                        byte nbRssi = dataA.dataValues[13 - 8];
-                                                                        byte mantissa = nbRssi;
-                                                                        mantissa &= 0x07;
-                                                                        byte exponent = nbRssi;
-                                                                        exponent >>= 3;
-                                                                        dataA.decodedRssi = 20 * log10(pow(2, exponent) * (1 + (mantissa / pow(2, 3))));
-                                                                    }
+                                                                    dataA.decodedRssi = decodeNarrowBandRSSI(dataA.dataValues[13 - 8]);
 
                                                                     byte bValue = dataA.dataValues[14 - 8];
                                                                     bValue &= 0x7F;
@@ -5119,16 +5240,7 @@ else if ((mRfidToReading[startIndex + 0] == (byte) 0x00 || mRfidToReading[startI
                                                                         index += epcLength;
                                                                     }
                                                                     if (dataValuesFull.length >= index + 1) {
-                                                                        if (true)
-                                                                            dataA.decodedRssi = decodeWideBandRSSI(dataValuesFull[index]);
-                                                                        else {
-                                                                            byte nbRssi = dataValuesFull[index];
-                                                                            byte mantissa = nbRssi;
-                                                                            mantissa &= 0x07;
-                                                                            byte exponent = nbRssi;
-                                                                            exponent >>= 3;
-                                                                            dataA.decodedRssi = 20 * log10(pow(2, exponent) * (1 + (mantissa / pow(2, 3))));
-                                                                        }
+                                                                        dataA.decodedRssi = decodeNarrowBandRSSI(dataValuesFull[index]);
                                                                         index++;
                                                                     }
                                                                     if (false)
@@ -5731,27 +5843,9 @@ boolean sendHostRegRequest(HostRegRequests hostRegRequests, boolean writeOperati
             boolean validRequest = false;
 
             if (isBleConnected() == false) return false;
-            if (false && bifMacAccessHistoryData(msgBuffer)) {
-                if (findMacAccessHistory(msgBuffer) >= 0) {
-                    appendToLog("setAlgoRetry: No sending as same data = " + byteArrayToString(msgBuffer));
-                    return true;
-                }
-            }
             addMacAccessHistory(msgBuffer);
             switch (hostRegRequests) {
                 case MAC_OPERATION:
-//                case MAC_VER:
-//                case MAC_LAST_COMMAND_DURATION:
-                    //needResponse = true;
-//                    validRequest = true;
-//                    break;
-//                case HST_CMNDIAGS:
-//                case HST_MBP_ADDR:
-//                case HST_MBP_DATA:
-//                case HST_OEM_ADDR:
-//                case HST_OEM_DATA:
-//                    validRequest = true;
-//                    break;
                 case HST_ANT_CYCLES:
                 case HST_ANT_DESC_SEL:
                 case HST_ANT_DESC_CFG:
@@ -5777,8 +5871,9 @@ boolean sendHostRegRequest(HostRegRequests hostRegRequests, boolean writeOperati
                 case HST_INV_ALG_PARM_1:
                 case HST_INV_ALG_PARM_2:
                 case HST_INV_ALG_PARM_3:
-//                    validRequest = true;
-//                    break;
+                case HST_INV_RSSI_FILTERING_CONFIG:
+                case HST_INV_RSSI_FILTERING_THRESHOLD:
+                case HST_INV_RSSI_FILTERING_COUNT:
                 case HST_INV_EPC_MATCH_CFG:
                 case HST_INV_EPCDAT_0_3:
                     validRequest = true;
diff --git a/cs108library4a/src/main/java/com/csl/cs108library4a/Cs108Library4A.java b/cs108library4a/src/main/java/com/csl/cs108library4a/Cs108Library4A.java
index 901a73b..3fd59c7 100644
--- a/cs108library4a/src/main/java/com/csl/cs108library4a/Cs108Library4A.java
+++ b/cs108library4a/src/main/java/com/csl/cs108library4a/Cs108Library4A.java
@@ -1,5 +1,9 @@
 package com.csl.cs108library4a;
 
+import static androidx.core.app.ActivityCompat.requestPermissions;
+
+import android.Manifest;
+import android.app.Activity;
 import android.bluetooth.BluetoothAdapter;
 import android.bluetooth.BluetoothDevice;
 import android.bluetooth.BluetoothProfile;
@@ -11,6 +15,7 @@
 import android.os.Build;
 import android.os.Handler;
 import androidx.annotation.Keep;
+import androidx.core.app.ActivityCompat;
 
 import android.widget.TextView;
 
@@ -89,7 +94,6 @@ public void onLeScan(final BluetoothDevice device, final int rssi, final byte[]
                 if (f.name != null) {
                     boolean matched = false;
                     if (f.name.contains("bluetooth_le")) matched = true;
-                    else if (f.name.contains("usb.host")) matched = true;
                     if (matched) appendToLogView("feature = " + f.name);
                 }
             }
@@ -178,6 +182,11 @@ boolean check9800(Cs108Library4A.Cs108ScanData scanResultA) {
         int iNewADLength = 0;
         byte[] newAD = new byte[0];
         int iNewADIndex = 0;
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S && ActivityCompat.checkSelfPermission(context, Manifest.permission.BLUETOOTH_CONNECT) != PackageManager.PERMISSION_GRANTED) {
+            appendToLog("requestPermissions BLUETOOTH_CONNECT 123");
+            requestPermissions((Activity) context, new String[]{Manifest.permission.BLUETOOTH_CONNECT}, 123);
+            return false;
+        }
         String strTemp = scanResultA.getDevice().getName();
         if (strTemp != null) appendToLog("Found name = " + strTemp + ", length = " + String.valueOf(strTemp.length()));
         for (byte bdata : scanResultA.getScanRecord()) {
@@ -279,8 +288,13 @@ public void run() {
                 appendToLog("abcc connectRunnable: still scanning. Stop scanning first");
                 scanLeDevice(false);
             } else if (bNeedReconnect) {
-                if (readerDeviceConnect == null) return;
-                else if (mBluetoothGatt == null) {
+                if (mBluetoothGatt != null) {
+                    appendToLog("abcc connectRunnable: mBluetoothGatt is null before connect. disconnect first");
+                    disconnect();
+                } else if (readerDeviceConnect == null) {
+                    appendToLog("abcc connectRunnable: exit with null readerDeviceConnect");
+                    return;
+                } else if (mBluetoothGatt == null) {
                     appendToLog("abcc connectRunnable: connect1 again");
                     connect1(null);
                     bNeedReconnect = false;
@@ -298,26 +312,15 @@ else if (mBluetoothGatt == null) {
         }
     };
     ReaderDevice readerDeviceConnect;
-    @Keep public boolean connect(ReaderDevice readerDevice) {
-        if (isBleConnected()) return true;
+    @Keep public void connect(ReaderDevice readerDevice) {
+        if (isBleConnected()) return;
         if (mBluetoothGatt != null) disconnect();
         if (readerDevice != null) readerDeviceConnect = readerDevice;
-        if (false) {
-            mHandler.removeCallbacks(runnableToggleConnection);
-            mHandler.post(runnableToggleConnection);
-            return true;
-        } else {
-            mHandler.removeCallbacks(connectRunnable);
-            mHandler.postDelayed(connectRunnable, 500);
-            return connect1(readerDevice);
-        }
+        mHandler.removeCallbacks(connectRunnable);
+        bNeedReconnect = true; mHandler.post(connectRunnable);
 	}
     boolean connect1(ReaderDevice readerDevice) {
         appendToLog("Connect with NULLreaderDevice = " + (readerDevice == null) + ", NULLreaderDeviceConnect = " + (readerDeviceConnect == null));
-        if (isBleScanning()) {
-            appendToLog("abcc still scanning. Stop scanning first");
-            scanLeDevice(false);
-        }
         if (readerDevice == null && readerDeviceConnect != null)    readerDevice = readerDeviceConnect;
         boolean result = false;
         if (readerDevice != null) {
@@ -364,9 +367,9 @@ public String checkVersion() {
         String macVersion = getMacVer();
         String hostVersion = hostProcessorICGetFirmwareVersion();
         String bluetoothVersion = getBluetoothICFirmwareVersion();
-        String strVersionRFID = "2.6.43"; String[] strRFIDVersions = strVersionRFID.split("\\.");
-        String strVersionBT = "1.0.14"; String[] strBTVersions = strVersionBT.split("\\.");
-        String strVersionHost = "1.0.15"; String[] strHostVersions = strVersionHost.split("\\.");
+        String strVersionRFID = "2.6.44"; String[] strRFIDVersions = strVersionRFID.split("\\.");
+        String strVersionBT = "1.0.16"; String[] strBTVersions = strVersionBT.split("\\.");
+        String strVersionHost = "1.0.17"; String[] strHostVersions = strVersionHost.split("\\.");
         String stringPopup = "";
         int icsModel = getcsModel();
 
@@ -401,7 +404,7 @@ public long getTagRate() {
         appendToLog("PowerLevel");
         setPowerLevel(300);
         setTagGroup(0, 0, 2);
-        setPopulation(30);
+        setPopulation(60);
         setInvAlgoNoSave(true);
         setCurrentLinkProfile(1);
     }
@@ -882,7 +885,7 @@ public String getEnvironmentalRSSI() {
         int iValue =  mRfidDevice.mRfidReaderChip.mRx000EngSetting.getwideRSSI();
         if (iValue < 0) return null;
         if (iValue > 255) return "Invalid data";
-        double dValue = mRfidDevice.mRfidReaderChip.decodeWideBandRSSI((byte)iValue);
+        double dValue = mRfidDevice.mRfidReaderChip.decodeNarrowBandRSSI((byte)iValue);
         return String.format("%.2f dB", dValue);
     }
 
@@ -2550,6 +2553,59 @@ public boolean setSelectCriteria(int index, boolean enable, int target, int acti
         return result;
     }
 
+    @Keep public boolean getRssiFilterEnable() {
+        int iValue = mRfidDevice.mRfidReaderChip.mRx000Setting.getRssiFilterType();
+        if (iValue < 0) return false;
+        iValue &= 0xF;
+        return (iValue > 0 ? true : false);
+    }
+    @Keep public int getRssiFilterType() {
+        int iValue = mRfidDevice.mRfidReaderChip.mRx000Setting.getRssiFilterType();
+        if (iValue < 0) return 0;
+        iValue &= 0xF;
+        if (iValue < 2) return 0;
+        return iValue - 1;
+    }
+    @Keep public int getRssiFilterOption() {
+        int iValue = mRfidDevice.mRfidReaderChip.mRx000Setting.getRssiFilterOption();
+        if (iValue < 0) return 0;
+        iValue &= 0xF;
+        return iValue;
+    }
+    @Keep public boolean setRssiFilterConfig(boolean enable, int rssiFilterType, int rssiFilterOption) {
+        int iValue = 0;
+        if (enable == false) iValue = 0;
+        else iValue = rssiFilterType + 1;
+        return mRfidDevice.mRfidReaderChip.mRx000Setting.setHST_INV_RSSI_FILTERING_CONFIG(iValue, rssiFilterOption);
+    }
+    @Keep public double getRssiFilterThreshold1() {
+        int iValue = mRfidDevice.mRfidReaderChip.mRx000Setting.getRssiFilterThreshold1();
+        appendToLog("iValue = " + iValue);
+        byte byteValue = (byte)(iValue & 0xFF);
+        appendToLog("byteValue = " + byteValue);
+        double dValue = mRfidDevice.mRfidReaderChip.decodeNarrowBandRSSI(byteValue);
+        appendToLog("dValue = " + dValue);
+        return dValue;
+    }
+    @Keep public double getRssiFilterThreshold2() {
+        int iValue = mRfidDevice.mRfidReaderChip.mRx000Setting.getRssiFilterThreshold2();
+        appendToLog("iValue = " + iValue);
+        byte byteValue = (byte)(iValue & 0xFF);
+        double dValue = mRfidDevice.mRfidReaderChip.decodeNarrowBandRSSI(byteValue);
+        return dValue;
+    }
+    @Keep public boolean setRssiFilterThreshold(double rssiFilterThreshold1, double rssiFilterThreshold2) {
+        appendToLog("rssiFilterThreshold = " + rssiFilterThreshold1 + ", " + rssiFilterThreshold2);
+        return mRfidDevice.mRfidReaderChip.mRx000Setting.setHST_INV_RSSI_FILTERING_THRESHOLD(mRfidDevice.mRfidReaderChip.encodeNarrowBandRSSI(rssiFilterThreshold1), mRfidDevice.mRfidReaderChip.encodeNarrowBandRSSI(rssiFilterThreshold2));
+    }
+    @Keep public long getRssiFilterCount() {
+        return mRfidDevice.mRfidReaderChip.mRx000Setting.getRssiFilterCount();
+    }
+    @Keep public boolean setRssiFilterCount(long rssiFilterCount) {
+        appendToLog("rssiFilterCount = " + rssiFilterCount);
+        return mRfidDevice.mRfidReaderChip.mRx000Setting.setHST_INV_RSSI_FILTERING_COUNT(rssiFilterCount);
+    }
+
     @Keep public boolean getInvMatchEnable() {
         return mRfidDevice.mRfidReaderChip.mRx000Setting.getInvMatchEnable() > 0 ? true : false;
     }
@@ -2981,7 +3037,7 @@ public void run() {
             if (isBleConnected() == false)  toggledConnection = true;
             if (toggledConnection) {
                 if (isBleConnected() == false) {
-                    if (connect1(readerDeviceConnect) == false) return;
+                    if (connect1(null) == false) return;
                 } else return;
             } else { disconnect(); appendToLog("done"); }
             mHandler.postDelayed(runnableToggleConnection, 500);
@@ -3746,6 +3802,7 @@ else if (mRfidDevice.isInventoring()) {
         return true;
     }
 
+    public final double dBuV_dBm_constant = 106.98;
     int rssiDisplaySelect = 1;
     @Keep public int getRssiDisplaySetting() { return rssiDisplaySelect; }
     @Keep public boolean setRssiDisplaySetting(int rssiDisplaySelect) {
@@ -3796,14 +3853,6 @@ public boolean setCsvColumnSelectSetting(int csvColumnSelect) {
             Cs108ScanData cs108ScanData = mScanResultList.get(0); mScanResultList.remove(0);
             return cs108ScanData;
         } else return null;
-/*        if (false) return mScanResultList;
-        ArrayList<UsbDevice> usbDevicesList = mUsbConnector.getUsbDeviceList();
-        ArrayList<Cs108ScanData> cs108SScanDataList = new ArrayList<Cs108ScanData>();
-        for (UsbDevice usbDevice: usbDevicesList) {
-            Cs108ScanData cs108RfidData = new Cs108ScanData(usbDevice.getDeviceName(), "CS108 USB DEVICE", 0, null);
-            cs108SScanDataList.add(cs108RfidData);
-        }
-        return cs108SScanDataList; */
     }
 
     @Keep public Rx000pkgData onRFIDEvent() {
diff --git a/cs108library4a/src/main/java/com/csl/cs108library4a/Utility.java b/cs108library4a/src/main/java/com/csl/cs108library4a/Utility.java
index c9f60e3..b87e001 100644
--- a/cs108library4a/src/main/java/com/csl/cs108library4a/Utility.java
+++ b/cs108library4a/src/main/java/com/csl/cs108library4a/Utility.java
@@ -102,6 +102,7 @@ void debugFileSetup() {
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
             if (mContext.checkSelfPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
                 writeExtPermission = false;
+                appendToLog("requestPermissions WRITE_EXTERNAL_STORAGE 1");
                 requestPermissions((Activity) mContext, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1);
                 return;
             }
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 35131ba..f566025 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
-#Fri Nov 13 10:39:40 CST 2020
+#Tue Dec 14 11:20:36 CST 2021
 distributionBase=GRADLE_USER_HOME
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.0.2-bin.zip
 distributionPath=wrapper/dists
-zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-all.zip
+zipStoreBase=GRADLE_USER_HOME