java - 传输端点错误

Question

我正在尝试通过蓝牙从我的 android 发送文本以显示在 arduino 的串行监视器中。我有一个按钮，当我点击它时应该发送文本，但我一直收到此错误。有人知道问题出在哪里吗？

 01-12 01:53:10.849: E/BluetoothSocket(25004): java.io.IOException: Transport endpoint is not connected
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at android.bluetooth.BluetoothSocket.writeNative(Native Method)
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at android.bluetooth.BluetoothSocket.write(BluetoothSocket.java:372)
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at android.bluetooth.BluetoothOutputStream.write(BluetoothOutputStream.java:89)
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at java.io.OutputStream.write(OutputStream.java:80)
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at com.example.BluetoothExample.Send.stream(Send.java:120)
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at com.example.BluetoothExample.Send$2.onClick(Send.java:57)
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at android.view.View.performClick(View.java:2579)
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at android.view.View$PerformClick.run(View.java:9246)
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at android.os.Handler.handleCallback(Handler.java:587)
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at android.os.Handler.dispatchMessage(Handler.java:92)
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at    android.os.Looper.loop(Looper.java:130)
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at android.app.ActivityThread.main(ActivityThread.java:3735)
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at java.lang.reflect.Method.invokeNative(Native Method)
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at java.lang.reflect.Method.invoke(Method.java:507)
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:904)
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:662)
 01-12 01:53:10.849: E/BluetoothSocket(25004):  at dalvik.system.NativeStart.main(Native Method)

我有一个非常简单的 arduino 代码。

 int incomingByte;
 char val;

 void setup() {
   pinMode(2, OUTPUT);
   Serial.begin(9600);
 }

 void loop() {

   if (Serial.available() > 0) {
     val = Serial.read();
     Serial.println(val);
     }
     delay(100);
   }

Answer 1

您是否尝试过将 println() 更改为 write()？ 如下所示:

if (Serial.available() > 0) {
     val = Serial.read();
     Serial.write(val);
}