diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index c44fcf96..ca222124 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -85,7 +85,7 @@
 
         tools:targetApi="28">
         <activity
-            android:name=".CertActivity"
+            android:name=".BridgeActivity"
             android:exported="true" />
         <activity
             android:name=".video.VideoActivity"
diff --git a/app/src/main/cpp/MicroPhoto.cpp b/app/src/main/cpp/MicroPhoto.cpp
index 1f256ce0..daa72e5a 100644
--- a/app/src/main/cpp/MicroPhoto.cpp
+++ b/app/src/main/cpp/MicroPhoto.cpp
@@ -806,6 +806,14 @@ Java_com_xypower_mpapp_MicroPhotoService_importPublicKey(
 #endif
 }
 
+extern "C" JNIEXPORT jint JNICALL
+Java_com_xypower_mpapp_MicroPhotoService_getGpioInt(
+        JNIEnv* env,
+        jclass cls, jint cmd) {
+
+    return GpioControl::getInt(cmd);
+}
+
 extern "C" JNIEXPORT jboolean JNICALL
 Java_com_xypower_mpapp_MicroPhotoService_genKeys(
         JNIEnv* env,
diff --git a/app/src/main/java/com/xypower/mpapp/BridgeActivity.java b/app/src/main/java/com/xypower/mpapp/BridgeActivity.java
new file mode 100644
index 00000000..9a79b9f9
--- /dev/null
+++ b/app/src/main/java/com/xypower/mpapp/BridgeActivity.java
@@ -0,0 +1,156 @@
+package com.xypower.mpapp;
+
+import androidx.appcompat.app.AppCompatActivity;
+
+import android.app.Activity;
+import android.content.Intent;
+import android.os.Bundle;
+import android.os.Handler;
+import android.text.TextUtils;
+import android.util.Base64;
+
+import com.xypower.common.FileUtils;
+import com.xypower.mpapp.v2.Camera2VideoActivity;
+
+import java.io.File;
+import java.nio.charset.StandardCharsets;
+
+public class BridgeActivity extends AppCompatActivity {
+
+    private final static String ACTION_IMP_PUBKEY = "imp_pubkey";
+    private final static String ACTION_GEN_KEYS = "gen_keys";
+    private final static String ACTION_CERT_REQ = "cert_req";
+    private final static String ACTION_BATTERY_VOLTAGE = "query_bv";
+    private final static String ACTION_RECORDING = "recording";
+
+    private final static int REQUEST_CODE_RECORDING = Camera2VideoActivity.REQUEST_CODE_RECORDING;
+
+    private Handler mHandler = null;
+    private boolean m3V3TurnedOn = false;
+    private boolean mAutoClose = true;
+
+    private String mVideoFilePath = null;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_cert);
+
+        mHandler = new Handler();
+
+        Intent intent = getIntent();
+        final String action = intent.getStringExtra("action");
+        if (!TextUtils.isEmpty(action)) {
+            if (TextUtils.equals(action, ACTION_IMP_PUBKEY)) {
+                String cert = intent.getStringExtra("cert");
+                String path = intent.getStringExtra("path");
+                int index = intent.getIntExtra("index", 1);
+
+                if (!TextUtils.isEmpty(cert)) {
+                    // Import
+                    // String cert = intent.getStringExtra("md5");
+                    byte[] content = Base64.decode(cert, Base64.DEFAULT);
+                    if (content != null) {
+                        MicroPhotoService.importPublicKey(index, content);
+                    }
+                } else if (TextUtils.isEmpty(path)) {
+                    String md5 = intent.getStringExtra("md5");
+                    File file = new File(path);
+                    if (file.exists() && file.isFile()) {
+                        MicroPhotoService.importPublicKeyFile(index, path, md5);
+                    }
+                }
+            } else if (TextUtils.equals(action, ACTION_GEN_KEYS)) {
+                int index = intent.getIntExtra("index", 0);
+                boolean res = MicroPhotoService.genKeys(index);
+                String path = intent.getStringExtra("path");
+                if (!TextUtils.isEmpty(path)) {
+                    FileUtils.ensureParentDirectoryExisted(path);
+                    FileUtils.writeTextFile(path, res ? "1" : "0");
+                }
+            } else if (TextUtils.equals(action, ACTION_CERT_REQ)) {
+                int index = intent.getIntExtra("index", 0);
+                int type = intent.getIntExtra("type", 0);
+                String subject = intent.getStringExtra("subject");
+                String path = intent.getStringExtra("path");
+                MicroPhotoService.genCertRequest(index, type, subject, path);
+            } else if (TextUtils.equals(action, ACTION_BATTERY_VOLTAGE)) {
+                String path = intent.getStringExtra("path");
+                // #define CMD_GET_CHARGING_BUS_VOLTAGE_STATE      112
+                // #define CMD_GET_BAT_VOL_STATE                   115
+                // #define CMD_GET_BAT_BUS_VOLTAGE_STATE           117
+                int bv = MicroPhotoService.getGpioInt(117);
+                int bcv = MicroPhotoService.getGpioInt(112);
+                if (!TextUtils.isEmpty(path)) {
+                    FileUtils.ensureParentDirectoryExisted(path);
+                    FileUtils.writeTextFile(path + ".tmp", Integer.toString(bv) + " " + Integer.toString(bcv));
+                    File file = new File(path + ".tmp");
+                    file.renameTo(new File(path));
+                }
+            }  else if (TextUtils.equals(action, ACTION_RECORDING)) {
+                String path = intent.getStringExtra("path");
+                int channel = intent.getIntExtra("channel", 1);
+                int cameraId = intent.getIntExtra("cameraId", -1);
+                int quality = intent.getIntExtra("quality", 0);
+                int width = intent.getIntExtra("width", 1280);
+                int height = intent.getIntExtra("height", 720);
+                int duration = intent.getIntExtra("duration", 15);
+                int orientation = intent.getIntExtra("orientation", 0);
+                long videoId = System.currentTimeMillis() / 1000;
+
+                String leftTopOsd = intent.getStringExtra("leftTopOsd");
+                String rightTopOsd = intent.getStringExtra("rightTopOsd");
+                String rightBottomOsd = intent.getStringExtra("rightBottomOsd");
+                String leftBottomOsd = intent.getStringExtra("leftBottomOsd");
+
+                if (cameraId == -1) {
+                    cameraId = channel - 1;
+                }
+
+                Intent recordingIntent = MicroPhotoService.makeRecordingIntent(getApplicationContext(),
+                        cameraId, videoId, duration, width, height, quality, orientation,
+                        leftTopOsd, rightTopOsd, rightBottomOsd, leftBottomOsd);
+
+                mVideoFilePath = path;
+                mAutoClose = false;
+
+                recordingIntent.putExtra("ActivityResult", true);
+                startActivityForResult(recordingIntent, REQUEST_CODE_RECORDING);
+            }
+        }
+
+        final Activity activity = this;
+        mHandler.postDelayed(new Runnable() {
+            @Override
+            public void run() {
+                activity.finish();
+            }
+        }, 2000);
+    }
+
+    @Override
+    protected void onDestroy() {
+        super.onDestroy();
+
+        if (m3V3TurnedOn) {
+            MicroPhotoService.setCam3V3Enable(false);
+        }
+    }
+
+    @Override
+    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
+        super.onActivityResult(requestCode, resultCode, data);
+
+        if (requestCode == REQUEST_CODE_RECORDING) {
+            if (mVideoFilePath != null) {
+                String path = data.getStringExtra("path");
+                if (path != null) {
+                    File file = new File(path);
+                    file.renameTo(new File(mVideoFilePath));
+                }
+            }
+            this.finish();
+        }
+    }
+
+}
\ No newline at end of file
diff --git a/app/src/main/java/com/xypower/mpapp/CertActivity.java b/app/src/main/java/com/xypower/mpapp/CertActivity.java
deleted file mode 100644
index 3887988d..00000000
--- a/app/src/main/java/com/xypower/mpapp/CertActivity.java
+++ /dev/null
@@ -1,79 +0,0 @@
-package com.xypower.mpapp;
-
-import androidx.appcompat.app.AppCompatActivity;
-
-import android.app.Activity;
-import android.content.Intent;
-import android.os.Bundle;
-import android.os.Handler;
-import android.text.TextUtils;
-import android.util.Base64;
-
-import com.xypower.common.FileUtils;
-
-import java.io.File;
-import java.nio.charset.StandardCharsets;
-
-public class CertActivity extends AppCompatActivity {
-
-    private final static String ACTION_IMP_PUBKEY = "imp_pubkey";
-    private final static String ACTION_GEN_KEYS = "gen_keys";
-    private final static String ACTION_CERT_REQ = "cert_req";
-
-    private Handler mHandler = null;
-
-    @Override
-    protected void onCreate(Bundle savedInstanceState) {
-        super.onCreate(savedInstanceState);
-        setContentView(R.layout.activity_cert);
-
-        mHandler = new Handler();
-
-        Intent intent = getIntent();
-        final String action = intent.getStringExtra("action");
-        if (!TextUtils.isEmpty(action)) {
-            if (TextUtils.equals(action, ACTION_IMP_PUBKEY)) {
-                String cert = intent.getStringExtra("cert");
-                String path = intent.getStringExtra("path");
-                int index = intent.getIntExtra("index", 1);
-
-                if (!TextUtils.isEmpty(cert)) {
-                    // Import
-                    // String cert = intent.getStringExtra("md5");
-                    byte[] content = Base64.decode(cert, Base64.DEFAULT);
-                    if (content != null) {
-                        MicroPhotoService.importPublicKey(index, content);
-                    }
-                } else if (TextUtils.isEmpty(path)) {
-                    String md5 = intent.getStringExtra("md5");
-                    File file = new File(path);
-                    if (file.exists() && file.isFile()) {
-                        MicroPhotoService.importPublicKeyFile(index, path, md5);
-                    }
-                }
-            } else if (TextUtils.equals(action, ACTION_GEN_KEYS)) {
-                int index = intent.getIntExtra("index", 0);
-                boolean res = MicroPhotoService.genKeys(index);
-                String path = intent.getStringExtra("path");
-                if (!TextUtils.isEmpty(path)) {
-                    FileUtils.ensureParentDirectoryExisted(path);
-                    FileUtils.writeTextFile(path, res ? "1" : "0");
-                }
-            } else if (TextUtils.equals(action, ACTION_CERT_REQ)) {
-                int index = intent.getIntExtra("index", 0);
-                int type = intent.getIntExtra("type", 0);
-                String subject = intent.getStringExtra("subject");
-                String path = intent.getStringExtra("path");
-                MicroPhotoService.genCertRequest(index, type, subject, path);
-            }
-        }
-
-        final Activity activity = this;
-        mHandler.postDelayed(new Runnable() {
-            @Override
-            public void run() {
-                activity.finish();
-            }
-        }, 2000);
-    }
-}
\ No newline at end of file
diff --git a/app/src/main/java/com/xypower/mpapp/MicroPhotoService.java b/app/src/main/java/com/xypower/mpapp/MicroPhotoService.java
index cd9d9539..3af905cb 100644
--- a/app/src/main/java/com/xypower/mpapp/MicroPhotoService.java
+++ b/app/src/main/java/com/xypower/mpapp/MicroPhotoService.java
@@ -481,7 +481,15 @@ public class MicroPhotoService extends Service {
     public void startRecording(int cameraId, long videoId, int duration, int width, int height, int quality, int orientation, String leftTopOsd, String rightTopOsd, String rightBottomOsd, String leftBottomOsd) {
         Context context = getApplicationContext();
         // Intent intent = new Intent(this, VideoActivity.class);
-        Intent intent = new Intent(this, Camera2VideoActivity.class);
+        Intent intent = makeRecordingIntent(context, cameraId, videoId, duration, width, height, quality, orientation,
+                leftTopOsd, rightTopOsd, rightBottomOsd, leftBottomOsd);
+
+        context.startActivity(intent);
+    }
+
+    public static Intent makeRecordingIntent(Context context, int cameraId, long videoId, int duration, int width, int height, int quality, int orientation, String leftTopOsd, String rightTopOsd, String rightBottomOsd, String leftBottomOsd) {
+        // Intent intent = new Intent(this, VideoActivity.class);
+        Intent intent = new Intent(context, Camera2VideoActivity.class);
 
         intent.putExtra("cameraId", cameraId);
         intent.putExtra("videoId", videoId);
@@ -496,7 +504,8 @@ public class MicroPhotoService extends Service {
         intent.putExtra("leftBottomOsd", leftBottomOsd);
 
         intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
-        startActivity(intent);
+
+        return intent;
     }
 
     protected boolean updateCaptureSchedule(long startTime) {
@@ -1157,6 +1166,8 @@ cellSignalStrengthGsm.getDbm();
     public static native boolean importPublicKey(int index, byte cert[]);
     public static native boolean genKeys(int index);
 
+    public native static int getGpioInt(int cmd);
+
     public static native String querySecVersion();
     public static native boolean genCertRequest(int index, int type, String subject, String outputPath);
     public static native boolean importPrivateKeyFile(int index, String outputPath, String md5);
diff --git a/app/src/main/java/com/xypower/mpapp/v2/Camera2VideoActivity.java b/app/src/main/java/com/xypower/mpapp/v2/Camera2VideoActivity.java
index ea8c82bc..1b349240 100644
--- a/app/src/main/java/com/xypower/mpapp/v2/Camera2VideoActivity.java
+++ b/app/src/main/java/com/xypower/mpapp/v2/Camera2VideoActivity.java
@@ -60,6 +60,8 @@ public class Camera2VideoActivity extends AppCompatActivity {
     public static final String ACTION_FINISH = "com.xypower.mvapp.ACT_FINISH";
     public static final String ACTION_MP_VIDEO_FINISHED = "com.xypower.mpapp.ACT_V_FINISHED";
 
+    public final static int REQUEST_CODE_RECORDING = 2;
+
     private static final int DEFAULT_FONT_SIZE = 32;
     private static final float DEFAULT_STROKE_WIDTH = 0.8f;
     private AutoFitGLView mPreviewView;
@@ -102,6 +104,8 @@ public class Camera2VideoActivity extends AppCompatActivity {
     private int mTimeMask = 0;
     private int mStatusBarHeight = -1;
 
+    private boolean mActivityResult = false;
+
     private static class OSD_ITEM
     {
         String text;
@@ -253,6 +257,8 @@ public class Camera2VideoActivity extends AppCompatActivity {
         mOSDRightTop = intent.getStringExtra("rightTopOsd");
         mOSDMargin = intent.getIntExtra("margin", 12);
 
+        mActivityResult = intent.getBooleanExtra("ActivityResult", false);
+
         mCameraWidth = mVideoWidth;
         mCameraHeight = mVideoHeight;
 
@@ -838,11 +844,15 @@ public class Camera2VideoActivity extends AppCompatActivity {
 
         // intent.setComponent(new ComponentName(packageName, receiverName));
 
-        // Log.i(TAG, "Notify recording videoId=" + Long.toString(mVideoId) + " " + path);
-        LocalBroadcastManager localBroadcastManager = LocalBroadcastManager.getInstance(getApplicationContext());
-        localBroadcastManager.sendBroadcast(intent);
+        if (mActivityResult) {
+            setResult(REQUEST_CODE_RECORDING, intent);
+        } else {
+            // Log.i(TAG, "Notify recording videoId=" + Long.toString(mVideoId) + " " + path);
+            LocalBroadcastManager localBroadcastManager = LocalBroadcastManager.getInstance(getApplicationContext());
+            localBroadcastManager.sendBroadcast(intent);
 
-        context.sendBroadcast(intent);
+            context.sendBroadcast(intent);
+        }
     }
 
     private String getVideoFilePath(Context context) {
diff --git a/app/src/main/res/layout/activity_cert.xml b/app/src/main/res/layout/activity_cert.xml
index 52f1a7d9..1e87b80c 100644
--- a/app/src/main/res/layout/activity_cert.xml
+++ b/app/src/main/res/layout/activity_cert.xml
@@ -4,6 +4,6 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    tools:context=".CertActivity">
+    tools:context=".BridgeActivity">
 
 </androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file
diff --git a/common/build.gradle b/common/build.gradle
index a488f0fa..04de2f89 100644
--- a/common/build.gradle
+++ b/common/build.gradle
@@ -6,7 +6,7 @@ android {
     compileSdk 33
 
     defaultConfig {
-        minSdk 25
+        minSdk 24
         targetSdk 28
 
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
diff --git a/common/src/main/java/com/xypower/common/FileUtils.java b/common/src/main/java/com/xypower/common/FileUtils.java
index c39dab4f..0456b01d 100644
--- a/common/src/main/java/com/xypower/common/FileUtils.java
+++ b/common/src/main/java/com/xypower/common/FileUtils.java
@@ -1,7 +1,15 @@
 package com.xypower.common;
 
+import android.text.TextUtils;
+
+import org.w3c.dom.Text;
+
+import java.io.BufferedReader;
 import java.io.File;
+import java.io.FileInputStream;
 import java.io.FileOutputStream;
+import java.io.InputStreamReader;
+import java.io.UnsupportedEncodingException;
 import java.util.ArrayList;
 import java.util.Date;
 import java.util.List;
@@ -111,4 +119,59 @@ public class FileUtils {
         }
     }
 
+    public static String readTextFile(String path) {
+        FileInputStream fis = null;
+        InputStreamReader inputStreamReader = null;
+        BufferedReader bufferedReader = null;
+        StringBuilder stringBuilder = null;
+        try {
+            File appCfgFile = new File(path);
+            if (appCfgFile.exists()) {
+                fis = new FileInputStream(appCfgFile);
+                inputStreamReader = new InputStreamReader(fis, "UTF-8");
+                bufferedReader = new BufferedReader(inputStreamReader);
+                stringBuilder = new StringBuilder();
+                String line;
+                while ((line = bufferedReader.readLine()) != null) {
+                    stringBuilder.append(line);
+                }
+            }
+        } catch (UnsupportedEncodingException e) {
+            e.printStackTrace();
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            if (bufferedReader != null) {
+                try {
+                    bufferedReader.close();
+                } catch (Exception ex) {
+                    ex.printStackTrace();
+                }
+            }
+            if (inputStreamReader != null) {
+                try {
+                    inputStreamReader.close();
+                } catch (Exception ex) {
+                    ex.printStackTrace();
+                }
+            }
+            if (fis != null) {
+                try {
+                    fis.close();
+                } catch (Exception ex) {
+                    ex.printStackTrace();
+                }
+            }
+        }
+
+        return stringBuilder == null ? null : stringBuilder.toString();
+    }
+
+    public static String[] splitLines(String output) {
+        output = output.replaceAll("\r\n", "\n");
+        output = output.replaceAll("\n\r", "\n");
+        output = output.replaceAll("\r", "\n");
+
+        return TextUtils.split(output,"\n");
+    }
 }
diff --git a/common/src/main/java/com/xypower/common/MicroPhotoContext.java b/common/src/main/java/com/xypower/common/MicroPhotoContext.java
index 44255f45..715162b2 100644
--- a/common/src/main/java/com/xypower/common/MicroPhotoContext.java
+++ b/common/src/main/java/com/xypower/common/MicroPhotoContext.java
@@ -4,8 +4,6 @@ import android.app.ActivityManager;
 import android.content.Context;
 import android.content.Intent;
 import android.content.pm.PackageManager;
-import android.net.ConnectivityManager;
-import android.net.Network;
 import android.os.Environment;
 import android.os.storage.StorageManager;
 import android.text.TextUtils;
@@ -16,14 +14,10 @@ import org.json.JSONArray;
 import org.json.JSONException;
 import org.json.JSONObject;
 
-import java.io.BufferedReader;
 import java.io.File;
-import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
-import java.io.InputStreamReader;
 import java.io.OutputStreamWriter;
-import java.io.UnsupportedEncodingException;
 import java.lang.reflect.Method;
 import java.util.List;
 
@@ -76,54 +70,6 @@ public class MicroPhotoContext {
         }
     }
 
-    public static String readTextFile(String path) {
-        FileInputStream fis = null;
-        InputStreamReader inputStreamReader = null;
-        BufferedReader bufferedReader = null;
-        StringBuilder stringBuilder = null;
-        try {
-            File appCfgFile = new File(path);
-            if (appCfgFile.exists()) {
-                fis = new FileInputStream(appCfgFile);
-                inputStreamReader = new InputStreamReader(fis, "UTF-8");
-                bufferedReader = new BufferedReader(inputStreamReader);
-                stringBuilder = new StringBuilder();
-                String line;
-                while ((line = bufferedReader.readLine()) != null) {
-                    stringBuilder.append(line);
-                }
-            }
-        } catch (UnsupportedEncodingException e) {
-            e.printStackTrace();
-        } catch (Exception e) {
-            e.printStackTrace();
-        } finally {
-            if (bufferedReader != null) {
-                try {
-                    bufferedReader.close();
-                } catch (Exception ex) {
-                    ex.printStackTrace();
-                }
-            }
-            if (inputStreamReader != null) {
-                try {
-                    inputStreamReader.close();
-                } catch (Exception ex) {
-                    ex.printStackTrace();
-                }
-            }
-            if (fis != null) {
-                try {
-                    fis.close();
-                } catch (Exception ex) {
-                    ex.printStackTrace();
-                }
-            }
-        }
-
-        return stringBuilder == null ? null : stringBuilder.toString();
-    }
-
     // 获取主存储卡路径
     public static String getPrimaryStoragePath(Context context) {
         try {
@@ -256,12 +202,17 @@ public class MicroPhotoContext {
 
     public static AppConfig getMpAppConfig(Context context) {
 
-        AppConfig appConfig = new AppConfig();
-
         String appPath = buildMpAppDir(context);
 
+        return getMpAppConfig(context, appPath + "data/App.json");
+    }
+
+    public static AppConfig getMpAppConfig(Context context, String path) {
+
+        AppConfig appConfig = new AppConfig();
+
         try {
-            String content = readTextFile(appPath + "data/App.json");
+            String content = FileUtils.readTextFile(path);
 
             JSONObject jsonObject = TextUtils.isEmpty(content) ? new JSONObject() : new JSONObject(content);
             appConfig.cmdid = jsonObject.optString(jsonObject.has("cmdid") ? "cmdid" : "CMDID", "");
@@ -291,7 +242,7 @@ public class MicroPhotoContext {
         String appPath = buildMasterAppDir(context);
 
         try {
-            String content = readTextFile(appPath + "data/Master.json");
+            String content = FileUtils.readTextFile(appPath + "data/Master.json");
 
             JSONObject jsonObject = TextUtils.isEmpty(content) ? new JSONObject() : new JSONObject(content);
             masterConfig.server = jsonObject.optString("server", "");
@@ -343,7 +294,7 @@ public class MicroPhotoContext {
 
             String path = appPath + "data/Master.json";
 
-            String content = readTextFile(path);
+            String content = FileUtils.readTextFile(path);
 
             JSONObject jsonObject = TextUtils.isEmpty(content) ? new JSONObject() : new JSONObject(content);
             jsonObject.put("server", masterConfig.server);
@@ -456,7 +407,7 @@ public class MicroPhotoContext {
                 dataPath.mkdirs();
             }
 
-            String content = readTextFile(path + "data/App.json");
+            String content = FileUtils.readTextFile(path + "data/App.json");
 
             JSONObject jsonObject = TextUtils.isEmpty(content) ? new JSONObject() : new JSONObject(content);
             jsonObject.put("CMDID", appConfig.cmdid);