README with SerialInputOutputManager for read() and port for write()

test the usually not used read/write variants

README.md

@@ -33,66 +33,67 @@ dependencies {
 }
 ```
 
-**2.** Copy [device_filter.xml](https://github.com/mik3y/usb-serial-for-android/blob/master/usbSerialExamples/src/main/res/xml/device_filter.xml) to your project's `res/xml/` directory.
-
-**3.** Configure your `AndroidManifest.xml` to notify your app when a device is attached (see [Android USB Host documentation](http://developer.android.com/guide/topics/connectivity/usb/host.html#discovering-d) for help).
+**2.** If the app should be notified when a device is attached, add 
+[device_filter.xml](https://github.com/mik3y/usb-serial-for-android/blob/master/usbSerialExamples/src/main/res/xml/device_filter.xml) 
+to your project's `res/xml/` directory and configure in your `AndroidManifest.xml`.
 
 ```xml
 <activity
     android:name="..."
     ...>
-  <intent-filter>
-    <action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" />
-  </intent-filter>
-  <meta-data
-      android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED"
-      android:resource="@xml/device_filter" />
+    <intent-filter>
+        <action android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED" />
+    </intent-filter>
+    <meta-data
+        android:name="android.hardware.usb.action.USB_DEVICE_ATTACHED"
+        android:resource="@xml/device_filter" />
 </activity>
 ```
 
-**4.** Use it! Example code snippet:
+**3.** Use it! Example code snippet:
 
 ```java
-// Find all available drivers from attached devices.
-UsbManager manager = (UsbManager) getSystemService(Context.USB_SERVICE);
-List<UsbSerialDriver> availableDrivers = UsbSerialProber.getDefaultProber().findAllDrivers(manager);
-if (availableDrivers.isEmpty()) {
-  return;
-}
+    // Find all available drivers from attached devices.
+    UsbManager manager = (UsbManager) getSystemService(Context.USB_SERVICE);
+    List<UsbSerialDriver> availableDrivers = UsbSerialProber.getDefaultProber().findAllDrivers(manager);
+    if (availableDrivers.isEmpty()) {
+        return;
+    }
 
-// Open a connection to the first available driver.
-UsbSerialDriver driver = availableDrivers.get(0);
-UsbDeviceConnection connection = manager.openDevice(driver.getDevice());
-if (connection == null) {
-  // You probably need to call UsbManager.requestPermission(driver.getDevice(), ..)
-  return;
-}
+    // Open a connection to the first available driver.
+    UsbSerialDriver driver = availableDrivers.get(0);
+    UsbDeviceConnection connection = manager.openDevice(driver.getDevice());
+    if (connection == null) {
+        // add UsbManager.requestPermission(driver.getDevice(), ..) handling here
+        return;
+    }
 
-// Read some data! Most have just one port (port 0).
-UsbSerialPort port = driver.getPorts().get(0);
-try {
-  port.open(connection);
-  port.setParameters(115200, 8, UsbSerialPort.STOPBITS_1, UsbSerialPort.PARITY_NONE);
-
-  byte buffer[] = new byte[16];
-  int numBytesRead = port.read(buffer, 1000);
-  Log.d(TAG, "Read " + numBytesRead + " bytes.");
-} catch (IOException e) {
-  // Deal with error.
-} finally {
-  port.close();
+    UsbSerialPort port = driver.getPorts().get(0); // Most devices have just one port (port 0)
+    port.open(connection);
+    port.setParameters(115200, 8, UsbSerialPort.STOPBITS_1, UsbSerialPort.PARITY_NONE);
+    usbIoManager = new SerialInputOutputManager(usbSerialPort, this);
+    Executors.newSingleThreadExecutor().submit(usbIoManager);
+```
+```java
+    port.write("hello".getBytes(), WRITE_WAIT_MILLIS);
+```
+```java
+@Override
+public void onNewData(byte[] data) {
+    runOnUiThread(() -> { textView.append(new String(data)); });
 }
 ```
+```java
+    port.close();
+```
 
-For a simple example, see the
-[UsbSerialExamples project](https://github.com/mik3y/usb-serial-for-android/blob/master/usbSerialExamples)
-in git, which is a simple application for reading and showing serial data.
+
+For a simple example, see
+[UsbSerialExamples](https://github.com/mik3y/usb-serial-for-android/blob/master/usbSerialExamples)
+folder in this project.
 
 For a more complete example, see separate github project 
-[SimpleUsbTerminal](https://github.com/kai-morich/SimpleUsbTerminal)
-
-A [simple Arduino application](https://github.com/mik3y/usb-serial-for-android/blob/master/arduino)
-is also available which can be used for testing.
+[SimpleUsbTerminal](https://github.com/kai-morich/SimpleUsbTerminal).
 
 ## Probing for Unrecognized Devices
 

test/serial_test/serial_test.ino

@@ -1,43 +0,0 @@
-/* Copyright 2012 Google Inc.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
- * USA.
- *
- * Project home page: http://code.google.com/p/usb-serial-for-android/
- */
-
-// Sample Arduino sketch for use with usb-serial-for-android.
-// Prints an ever-increasing counter, and writes back anything
-// it receives.
-
-static int counter = 0;
-void setup() {
-  Serial.begin(115200);
-}
-
-void loop() {
-  Serial.print("Tick #");
-  Serial.print(counter++, DEC);
-  Serial.print("\n");
-
-  if (Serial.peek() != -1) {
-    Serial.print("Read: ");
-    do {
-      Serial.print((char) Serial.read());
-    } while (Serial.peek() != -1);
-    Serial.print("\n");
-  }
-  delay(1000);
-}

usbSerialForAndroid/src/androidTest/java/com/hoho/android/usbserial/DeviceTest.java

@@ -194,22 +194,7 @@ public class DeviceTest implements SerialInputOutputManager.Listener {
         try {
             telnetRead(0);
         } catch (Exception ignored) {}
-
-        try {
-            usbIoManager.setListener(null);
-            usbIoManager.stop();
-        } catch (Exception ignored) {}
-        try {
-            usbSerialPort.setDTR(false);
-            usbSerialPort.setRTS(false);
-            usbSerialPort.close();
-        } catch (Exception ignored) {}
-        try {
-            usbDeviceConnection.close();
-        } catch (Exception ignored) {}
-        usbIoManager = null;
-        usbSerialPort = null;
-        usbDeviceConnection = null;
+        usbClose();
         usbSerialDriver = null;
     }
 
@@ -261,10 +246,15 @@ public class DeviceTest implements SerialInputOutputManager.Listener {
 
     private void usbClose() {
         if (usbIoManager != null) {
+            usbIoManager.setListener(null);
             usbIoManager.stop();
-            usbIoManager = null;
         }
         if (usbSerialPort != null) {
+            try {
+                usbSerialPort.setDTR(false);
+                usbSerialPort.setRTS(false);
+            } catch (Exception ignored) {
+            }
             try {
                 usbSerialPort.close();
             } catch (IOException ignored) {
@@ -274,6 +264,18 @@ public class DeviceTest implements SerialInputOutputManager.Listener {
         if(usbDeviceConnection != null)
             usbDeviceConnection.close();
         usbDeviceConnection = null;
+        if(usbIoManager != null) {
+            for(int i=0; i<2000; i++) {
+                if(SerialInputOutputManager.State.STOPPED == usbIoManager.getState()) break;
+                try {
+                    Thread.sleep(1);
+                } catch (InterruptedException e) {
+                    e.printStackTrace();
+                }
+            }
+            assertEquals(SerialInputOutputManager.State.STOPPED, usbIoManager.getState());
+            usbIoManager = null;
+        }
     }
 
     private void usbOpen(boolean withIoManager) throws Exception {
@@ -520,6 +522,11 @@ public class DeviceTest implements SerialInputOutputManager.Listener {
             usbSerialPort.close();
         } catch (IOException ignored) {
         }
+
+        if (usbSerialDriver instanceof Cp21xxSerialDriver) { // why needed?
+            usbIoManager.stop();
+            usbIoManager = null;
+        }
         // full re-open supported
         usbClose();
         usbOpen(true);
@@ -640,8 +647,8 @@ public class DeviceTest implements SerialInputOutputManager.Listener {
                     assertNotEquals(data1, buf1);
                     assertNotEquals(data2, buf2);
                 }
-                assertThat("42000/8N1", data1, equalTo(buf1));
             } else {
+                assertThat("42000/8N1", data1, equalTo(buf1));
                 assertThat("42000/8N1", data2, equalTo(buf2));
             }
         }
@@ -1109,4 +1116,85 @@ public class DeviceTest implements SerialInputOutputManager.Listener {
 
         // todo: purge receive buffer
     }
+
+    @Test
+    // WriteAsync rarely makes sense, as data is not written until something is read
+    public void writeAsync() throws Exception {
+        if (usbSerialDriver instanceof FtdiSerialDriver)
+            return; // periodically sends status messages, so does not block here
+        usbParameters(19200, 8, 1, UsbSerialPort.PARITY_NONE);
+        telnetParameters(19200, 8, 1, UsbSerialPort.PARITY_NONE);
+
+        SerialInputOutputManager ioManager;
+        ioManager = new SerialInputOutputManager(null);
+        assertEquals(null, ioManager.getListener());
+        ioManager.setListener(this);
+        assertEquals(this, ioManager.getListener());
+        ioManager = new SerialInputOutputManager(null, this);
+        assertEquals(this, ioManager.getListener());
+
+        byte[] data, buf = new byte[]{1};
+        int len;
+        usbIoManager.writeAsync(buf);
+        usbIoManager.writeAsync(buf);
+        data = telnetRead(1);
+        assertEquals(0, data.length);
+        telnetWrite(buf);
+        data = usbRead(1);
+        assertEquals(1, data.length);
+        data = telnetRead(2);
+        assertEquals(2, data.length);
+    }
+
+    @Test
+    // Blocking read should be avoided in the UI thread, as it makes the app unresponsive.
+    // You better use the SerialInputOutputManager.
+    //
+    // With the change from bulkTransfer to queued requests, the read timeout has no effect
+    // and the call blocks until close() if no data is available!
+    // The change from bulkTransfer to queued requests was necessary to prevent data loss.
+    public void readSync() throws Exception {
+        if (usbSerialDriver instanceof FtdiSerialDriver)
+            return; // periodically sends status messages, so does not block here
+
+        Runnable closeThread = new Runnable() {
+            @Override
+            public void run() {
+                try {
+                    Thread.sleep(100);
+                } catch (InterruptedException e) {
+                    e.printStackTrace();
+                }
+                usbClose();
+            }
+        };
+
+        usbClose();
+        usbOpen(false);
+        usbParameters(19200, 8, 1, UsbSerialPort.PARITY_NONE);
+        telnetParameters(19200, 8, 1, UsbSerialPort.PARITY_NONE);
+
+        byte[] buf = new byte[]{1};
+        int len;
+        long time;
+        telnetWrite(buf);
+        len = usbSerialPort.read(buf, 0); // not blocking because data is available
+        assertEquals(1, len);
+
+        time = System.currentTimeMillis();
+        Executors.newSingleThreadExecutor().submit(closeThread);
+        len = usbSerialPort.read(buf, 0); // blocking until close()
+        assertEquals(0, len);
+        assertTrue(System.currentTimeMillis()-time >= 100);
+
+        usbOpen(false);
+        usbParameters(19200, 8, 1, UsbSerialPort.PARITY_NONE);
+        telnetParameters(19200, 8, 1, UsbSerialPort.PARITY_NONE);
+
+        time = System.currentTimeMillis();
+        Executors.newSingleThreadExecutor().submit(closeThread);
+        len = usbSerialPort.read(buf, 10); // timeout not used any more -> blocking until close()
+        assertEquals(0, len);
+        assertTrue(System.currentTimeMillis()-time >= 100);
+   }
 }

usbSerialForAndroid/src/main/java/com/hoho/android/usbserial/util/SerialInputOutputManager.java

@@ -50,7 +50,7 @@ public class SerialInputOutputManager implements Runnable {
     // Synchronized by 'mWriteBuffer'
     private final ByteBuffer mWriteBuffer = ByteBuffer.allocate(BUFSIZ);
 
-    private enum State {
+    public enum State {
         STOPPED,
         RUNNING,
         STOPPING
@@ -111,7 +111,7 @@ public class SerialInputOutputManager implements Runnable {
         }
     }
 
-    private synchronized State getState() {
+    public synchronized State getState() {
         return mState;
     }