Add code that makes the board enter remote mode

src/net/hkzlab/dupal/App.java

@@ -1,9 +1,17 @@
 package net.hkzlab.dupal;
 
-import net.hkzlab.dupal.dupalproto.DuPALProto;
+import net.hkzlab.dupal.boardio.DuPALManager;
 
 public class App {
     public static void main(String[] args) throws Exception {
+        DuPALManager dpm = new DuPALManager("/dev/ttyUSB0");
 
+        try {
+            System.out.println(dpm.enterRemoteMode());
+
+        } finally {
+            dpm.cleanup();
+        }
+        
     }
 }

src/net/hkzlab/dupal/boardio/DuPALManager.java

@@ -0,0 +1,104 @@
+package net.hkzlab.dupal.boardio;
+
+import static jssc.SerialPort.*;
+
+import jssc.SerialPort;
+import jssc.SerialPortException;
+import jssc.SerialPortTimeoutException;
+
+public class DuPALManager {
+    private SerialPort serport = null;
+
+
+    private final static String REMOTE_MODE_STRING = "REMOTE_CONTROL_ENABLED";
+
+    public DuPALManager(final String serPort) {
+        serport = new SerialPort(serPort);
+
+        try {
+            serport.openPort();
+        } catch (final SerialPortException e) {
+            e.printStackTrace();
+            serport = null;
+        }
+
+        if (serport != null) {
+            try {
+                serport.setParams(BAUDRATE_19200, DATABITS_8, STOPBITS_1, PARITY_NONE);
+            } catch (final SerialPortException e) {
+                e.printStackTrace();
+                try {
+                    serport.closePort();
+                    serport = null;
+                } catch (final SerialPortException e1) { ; }
+            }
+        }
+    }
+
+    private void resetBoard() {
+        if (serport != null && serport.isOpened()) {
+            try {
+                serport.setDTR(true);
+                try {
+                    Thread.sleep(1000);
+                } catch (final InterruptedException e) {
+                }
+                ;
+                serport.setDTR(false);
+            } catch (final SerialPortException e) {
+                e.printStackTrace();
+            }
+        }
+    }
+
+    private void purgeRX() {
+        if(serport != null && serport.isOpened()) {
+            while(true) {
+                try { serport.readString(10, 100); }
+                catch (SerialPortTimeoutException | SerialPortException e) { break; }
+            }
+        }
+    }
+
+    public boolean enterRemoteMode() {
+        if (serport != null && serport.isOpened()) {
+            resetBoard();
+            try {
+                Thread.sleep(6000);
+            } catch (final InterruptedException e) {}
+            
+            // Wait for it to boot
+            try {
+                serport.purgePort(PURGE_RXABORT | PURGE_TXCLEAR);
+                purgeRX();
+
+                serport.writeByte((byte) 0x78); // 'x' in ascii
+                try { Thread.sleep(100); } catch(InterruptedException e) {};
+                final String response = serport.readString();
+
+                if ((response != null)) {
+                    if (response.trim().equals(REMOTE_MODE_STRING))
+                        return true;
+                    else
+                        return false;
+                } else
+                    return false;
+
+            } catch (SerialPortException e) {
+                e.printStackTrace();
+                return false;
+            }
+        }
+
+        return false;
+    }
+
+    public void cleanup() {
+        try {
+            if ((serport != null) && serport.isOpened())
+                serport.closePort();
+        } catch (final SerialPortException e) {
+            e.printStackTrace();
+        }
+    }
+}