diff --git a/usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/CommonUsbSerialPort.java b/usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/CommonUsbSerialPort.java
index 89ea337..a86cc79 100644
--- a/usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/CommonUsbSerialPort.java
+++ b/usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/CommonUsbSerialPort.java
@@ -221,6 +221,10 @@ public abstract class CommonUsbSerialPort implements UsbSerialPort {
         return offset;
     }
 
+    @Override
+    public boolean isOpen() {
+        return mConnection != null;
+    }
 
     @Override
     public abstract void setParameters(int baudRate, int dataBits, int stopBits, int parity) throws IOException;
diff --git a/usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/UsbSerialPort.java b/usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/UsbSerialPort.java
index 1774853..2e481e2 100644
--- a/usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/UsbSerialPort.java
+++ b/usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/driver/UsbSerialPort.java
@@ -226,4 +226,9 @@ public interface UsbSerialPort extends Closeable {
      */
     public boolean purgeHwBuffers(boolean purgeWriteBuffers, boolean purgeReadBuffers) throws IOException;
 
+    /**
+     * @return the current state of the connection
+     */
+    public boolean isOpen();
+
 }