diff --git a/usbserial/src/main/java/com/felhr/usbserial/FTDISerialDevice.java b/usbserial/src/main/java/com/felhr/usbserial/FTDISerialDevice.java
index f44c331..9aa824b 100644
--- a/usbserial/src/main/java/com/felhr/usbserial/FTDISerialDevice.java
+++ b/usbserial/src/main/java/com/felhr/usbserial/FTDISerialDevice.java
@@ -689,6 +689,63 @@ public class FTDISerialDevice extends UsbSerialDevice
         return readen;
     }
 
+    @Override
+    public int syncRead(byte[] buffer, int offset, int length, int timeout) {
+
+        long beginTime = System.currentTimeMillis();
+        long stopTime = beginTime + timeout;
+
+        if(asyncMode)
+        {
+            return -1;
+        }
+
+        if(buffer == null)
+        {
+            return 0;
+        }
+
+        int n = length / 62;
+        if(length % 62 != 0)
+        {
+            n++;
+        }
+
+        byte[] tempBuffer = new byte[length + n * 2];
+
+        int readen = 0;
+
+        do
+        {
+            int timeLeft = 0;
+            if(timeout > 0)
+            {
+                timeLeft = (int) (stopTime - System.currentTimeMillis());
+                if (timeLeft <= 0)
+                {
+                    break;
+                }
+            }
+
+            int numberBytes = connection.bulkTransfer(inEndpoint, tempBuffer, tempBuffer.length, timeLeft);
+
+            if(numberBytes > 2) // Data received
+            {
+                byte[] newBuffer = this.ftdiUtilities.adaptArray(tempBuffer);
+                System.arraycopy(newBuffer, 0, buffer, offset, length);
+
+                int p = numberBytes / 64;
+                if(numberBytes % 64 != 0)
+                {
+                    p++;
+                }
+                readen = numberBytes - p * 2;
+            }
+        }while(readen <= 0);
+
+        return readen;
+    }
+
     private static final byte[] skip = new byte[2];
 
     /**
diff --git a/usbserial/src/main/java/com/felhr/usbserial/SerialInputStream.java b/usbserial/src/main/java/com/felhr/usbserial/SerialInputStream.java
index afa8448..458e28e 100644
--- a/usbserial/src/main/java/com/felhr/usbserial/SerialInputStream.java
+++ b/usbserial/src/main/java/com/felhr/usbserial/SerialInputStream.java
@@ -54,6 +54,28 @@ public class SerialInputStream extends InputStream
         return device.syncRead(b, timeout);
     }
 
+    @Override
+    public int read(byte b[], int off, int len)
+    {
+        if(off < 0 ){
+            throw new IndexOutOfBoundsException("Offset must be >= 0");
+        }
+
+        if(len < 0){
+            throw new IndexOutOfBoundsException("Length must positive");
+        }
+
+        if(len > b.length - off) {
+            throw new IndexOutOfBoundsException("Length greater than b.length - off");
+        }
+
+        if (off == 0 && len == b.length) {
+            return read(b);
+        }
+
+        return device.syncRead(b, off, len, timeout);
+    }
+
     @Override
     public int available() throws IOException {
         if(bufferSize > 0)
diff --git a/usbserial/src/main/java/com/felhr/usbserial/SerialOutputStream.java b/usbserial/src/main/java/com/felhr/usbserial/SerialOutputStream.java
index 31b13cf..b1da2fd 100644
--- a/usbserial/src/main/java/com/felhr/usbserial/SerialOutputStream.java
+++ b/usbserial/src/main/java/com/felhr/usbserial/SerialOutputStream.java
@@ -25,6 +25,29 @@ public class SerialOutputStream extends OutputStream
         device.syncWrite(b, timeout);
     }
 
+    @Override
+    public void write(byte b[], int off, int len)
+    {
+        if(off < 0 ){
+            throw new IndexOutOfBoundsException("Offset must be >= 0");
+        }
+
+        if(len < 0){
+            throw new IndexOutOfBoundsException("Length must positive");
+        }
+
+        if(off + len > b.length) {
+            throw new IndexOutOfBoundsException("off + length greater than buffer length");
+        }
+
+        if (off == 0 && len == b.length) {
+            write(b);
+            return;
+        }
+
+        device.syncWrite(b, off, len, timeout);
+    }
+
     public void setTimeout(int timeout) {
         this.timeout = timeout;
     }
diff --git a/usbserial/src/main/java/com/felhr/usbserial/UsbSerialDevice.java b/usbserial/src/main/java/com/felhr/usbserial/UsbSerialDevice.java
index 5be2083..fe24aa4 100644
--- a/usbserial/src/main/java/com/felhr/usbserial/UsbSerialDevice.java
+++ b/usbserial/src/main/java/com/felhr/usbserial/UsbSerialDevice.java
@@ -5,6 +5,7 @@ import com.felhr.deviceids.CP210xIds;
 import com.felhr.deviceids.FTDISioIds;
 import com.felhr.deviceids.PL2303Ids;
 
+import android.annotation.TargetApi;
 import android.hardware.usb.UsbConstants;
 import android.hardware.usb.UsbDevice;
 import android.hardware.usb.UsbDeviceConnection;
@@ -216,6 +217,35 @@ public abstract class UsbSerialDevice implements UsbSerialInterface
         return connection.bulkTransfer(inEndpoint, buffer, buffer.length, timeout);
     }
 
+    @TargetApi(18)
+    @Override
+    public int syncWrite(byte[] buffer, int offset, int length, int timeout) {
+        if(!asyncMode)
+        {
+            if(buffer == null)
+                return 0;
+
+            return connection.bulkTransfer(outEndpoint, buffer, offset, length, timeout);
+        }else
+        {
+            return -1;
+        }
+    }
+
+    @TargetApi(18)
+    @Override
+    public int syncRead(byte[] buffer, int offset, int length, int timeout) {
+        if(asyncMode)
+        {
+            return -1;
+        }
+
+        if (buffer == null)
+            return 0;
+
+        return connection.bulkTransfer(inEndpoint, buffer, offset, length, timeout);
+    }
+
     // Serial port configuration
     @Override
     public abstract void setBaudRate(int baudRate);
diff --git a/usbserial/src/main/java/com/felhr/usbserial/UsbSerialInterface.java b/usbserial/src/main/java/com/felhr/usbserial/UsbSerialInterface.java
index 952b184..ffcbb34 100644
--- a/usbserial/src/main/java/com/felhr/usbserial/UsbSerialInterface.java
+++ b/usbserial/src/main/java/com/felhr/usbserial/UsbSerialInterface.java
@@ -38,6 +38,8 @@ public interface UsbSerialInterface
     boolean syncOpen();
     int syncWrite(byte[] buffer, int timeout);
     int syncRead(byte[] buffer, int timeout);
+    int syncWrite(byte[] buffer, int offset, int length, int timeout);
+    int syncRead(byte[] buffer, int offset, int length, int timeout);
     void syncClose();
 
     // Serial port configuration