diff --git a/app/src/main/java/com/shuwei/intelligent/shelves/serial/SerialPortManager.kt b/app/src/main/java/com/shuwei/intelligent/shelves/serial/SerialPortManager.kt
index 4e9b041..bdeaa23 100644
--- a/app/src/main/java/com/shuwei/intelligent/shelves/serial/SerialPortManager.kt
+++ b/app/src/main/java/com/shuwei/intelligent/shelves/serial/SerialPortManager.kt
@@ -13,8 +13,9 @@ import java.nio.charset.Charset
 import java.util.Locale
 
 object SerialPortManager {
-    private const val portName: String = "/dev/ttyS1"
-    private const val baudRate: Int = 115200
+
+    private const val PORT_NAME: String = "/dev/ttyS1"
+    private const val BAUD_RATE: Int = 115200
     private var serialPort: AndroidSerialPort? = null
 
     //    private var serialPort: SerialPort? = null
@@ -25,8 +26,8 @@ object SerialPortManager {
         return try {
             serialPort = SerialPortFactory.create().apply {
                 open(
-                    portName = portName,
-                    baudRate = baudRate,
+                    portName = PORT_NAME,
+                    baudRate = BAUD_RATE,
                     dataBits = 8,
                     stopBits = 1,
                     parity = SerialPort.PARITY_NONE