diff --git a/app/src/main/java/com/casic/detector/common/view/MainActivity.kt b/app/src/main/java/com/casic/detector/common/view/MainActivity.kt
index f949269..38b6d60 100644
--- a/app/src/main/java/com/casic/detector/common/view/MainActivity.kt
+++ b/app/src/main/java/com/casic/detector/common/view/MainActivity.kt
@@ -492,35 +492,36 @@
     private fun openSerialPort() {
         binding.stopFreeTaskButton.visibility = View.VISIBLE
         isFreeTask = true
+        searchMarkerTimer = Timer()
         serialPortService?.openSerialPort(object : OnSerialPortDataListener {
             override fun write(outStream: OutputStream) {
-                searchMarkerTimer = Timer()
-                searchMarkerTimer?.schedule(object : TimerTask() {
-                    override fun run() {
-                        outStream.write('2'.code)
-                        outStream.flush()
+                runOnUiThread {
+                    searchMarkerTimer?.schedule(object : TimerTask() {
+                        override fun run() {
+                            outStream.write('2'.code)
+                            outStream.flush()
 
-                        Thread.sleep(50)
+                            Thread.sleep(50)
 
-                        outStream.write('6'.code)
-                        outStream.flush()
-                    }
-                }, 0, 200)
+                            outStream.write('6'.code)
+                            outStream.flush()
+                        }
+                    }, 0, 200)
+                }
             }
 
             override fun onDataReceived(buffer: ByteArray) {
                 val hex = buffer.toHex()
+                //只响一次，因为探测频率高，所以依旧是连续的报警声
+                soundPool.play(soundResourceId, 1f, 1f, 0, 0, 1f)
                 if (hex.startsWith("4E")) {
-                    //只响一次，因为探测频率高，所以依旧是连续的报警声
-                    soundPool.play(soundResourceId, 1f, 1f, 0, 0, 1f)
-
                     try {
                         val energyResponse = hex.take(10).hexToString()
                         val energy = energyResponse.substring(1).toInt()
                         if (energy <= 1500 && detailDialog.isShowing) {
                             detailDialog.dismiss()
                         }
-                    }catch (e:NumberFormatException){
+                    } catch (e: NumberFormatException) {
                         e.printStackTrace()
                     }
                 }