diff --git a/mcu/interface/service/stacklib/bitstream.h b/mcu/interface/service/stacklib/bitstream.h
new file mode 100644
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+++ b/mcu/interface/service/stacklib/bitstream.h
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+/*****************************************************************************
+*  Copyright Statement:
+*  --------------------
+*  This software is protected by Copyright and the information contained
+*  herein is confidential. The software may not be copied and the information
+*  contained herein may not be used or disclosed except with the written
+*  permission of MediaTek Inc. (C) 2005
+*
+*  BY OPENING THIS FILE, BUYER HEREBY UNEQUIVOCALLY ACKNOWLEDGES AND AGREES
+*  THAT THE SOFTWARE/FIRMWARE AND ITS DOCUMENTATIONS ("MEDIATEK SOFTWARE")
+*  RECEIVED FROM MEDIATEK AND/OR ITS REPRESENTATIVES ARE PROVIDED TO BUYER ON
+*  AN "AS-IS" BASIS ONLY. MEDIATEK EXPRESSLY DISCLAIMS ANY AND ALL WARRANTIES,
+*  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF
+*  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NONINFRINGEMENT.
+*  NEITHER DOES MEDIATEK PROVIDE ANY WARRANTY WHATSOEVER WITH RESPECT TO THE
+*  SOFTWARE OF ANY THIRD PARTY WHICH MAY BE USED BY, INCORPORATED IN, OR
+*  SUPPLIED WITH THE MEDIATEK SOFTWARE, AND BUYER AGREES TO LOOK ONLY TO SUCH
+*  THIRD PARTY FOR ANY WARRANTY CLAIM RELATING THERETO. MEDIATEK SHALL ALSO
+*  NOT BE RESPONSIBLE FOR ANY MEDIATEK SOFTWARE RELEASES MADE TO BUYER'S
+*  SPECIFICATION OR TO CONFORM TO A PARTICULAR STANDARD OR OPEN FORUM.
+*
+*  BUYER'S SOLE AND EXCLUSIVE REMEDY AND MEDIATEK'S ENTIRE AND CUMULATIVE
+*  LIABILITY WITH RESPECT TO THE MEDIATEK SOFTWARE RELEASED HEREUNDER WILL BE,
+*  AT MEDIATEK'S OPTION, TO REVISE OR REPLACE THE MEDIATEK SOFTWARE AT ISSUE,
+*  OR REFUND ANY SOFTWARE LICENSE FEES OR SERVICE CHARGE PAID BY BUYER TO
+*  MEDIATEK FOR SUCH MEDIATEK SOFTWARE AT ISSUE. 
+*
+*  THE TRANSACTION CONTEMPLATED HEREUNDER SHALL BE CONSTRUED IN ACCORDANCE
+*  WITH THE LAWS OF THE STATE OF CALIFORNIA, USA, EXCLUDING ITS CONFLICT OF
+*  LAWS PRINCIPLES.  ANY DISPUTES, CONTROVERSIES OR CLAIMS ARISING THEREOF AND
+*  RELATED THERETO SHALL BE SETTLED BY ARBITRATION IN SAN FRANCISCO, CA, UNDER
+*  THE RULES OF THE INTERNATIONAL CHAMBER OF COMMERCE (ICC).
+*
+*****************************************************************************/
+
+/*****************************************************************************
+ *
+ * Filename:
+ * ---------
+ *   bitstream.h
+ *
+ * Project:
+ * --------
+ *   Maui_Software
+ *
+ * Description:
+ * ------------
+ *   BitStream allows sequential reading and writing of bit fields.
+ *
+ * Author:
+ * -------
+ * -------
+ *
+ *============================================================================
+ *             HISTORY
+ * Below this line, this part is controlled by PVCS VM. DO NOT MODIFY!!
+ *------------------------------------------------------------------------------
+ * removed!
+ * removed!
+ * removed!
+ *
+ * removed!
+ * removed!
+ * removed!
+ *
+ * removed!
+ * removed!
+ * removed!
+ *
+ * removed!
+ * removed!
+ * removed!
+ * removed!
+ * removed!
+ * removed!
+ * removed!
+ * removed!
+ * removed!
+ * removed!
+ *------------------------------------------------------------------------------
+ * Upper this line, this part is controlled by PVCS VM. DO NOT MODIFY!!
+ *============================================================================
+ ****************************************************************************/
+
+/*********************************************************************
+   (C) _____ (year of first publication) Sasken communication
+   Technologies Limited, All rights reserved.
+*   This file provides a template for .c files. This space
+*   should be used to describe the file contents
+*   Component-specific prefix : xxxx
+*********************************************************************/
+ 
+#ifndef _BITSTREAM_H
+#define _BITSTREAM_H
+/*RHR*/
+#include "kal_general_types.h"
+/*RHR*/
+/* BitStream
+ *
+ *      A bit stream allows bit fields to be read and written to,
+ *      just like an byte stream allows byte to be read and written
+ *      to. Reading and writing of bit fields is done to an underlying
+ *      byte stream, in network byte order.
+ *
+ *      bit_stream_init sets the underlying byte stream and the
+ *      current read/write position within the byte stream. Can also
+ *      be called when a seek to a new position is desired.
+
+ *      The values which are read by bit_stream_read are returned as
+ *      native unsigned integers.
+ *
+ *      Similarly the values which are passed to bit_stream_write for
+ *      writing should be passed as native unsigned integers.
+ *
+ *      Both bit_stream_read and bit_stream_write, increment the
+ *      current position,to facilitate sequential operation.
+ *      bit_stream_cur_pos returns the number of bytes, the underlying
+ *      byte pointer has been moved since bit_stream_init.
+ *
+ */
+
+typedef struct bit_stream {
+    kal_uint8    *byte_stream; /* Pointer to underlying byte stream. */
+    kal_uint8    *byte_stream_start;
+    kal_uint8    offset;    /* Offset in bits from MSB of byte_stream */
+} bit_stream;
+
+/* Initialise Bit stream operations
+ *
+ *                                offset
+ *                                |
+ *                                V
+ *               /-------------------------------\
+ * byte_stream-->|   |   |   |   |   |   |   |   |
+ *               |---|---|---|---|---|---|---|---|
+ *               |   |   |   |   |   |   |   |   |
+ *               |---|---|---|---|---|---|---|---|
+ *               |   |   |   |   |   |   |   |   |
+ *               |---|---|---|---|---|---|---|---|
+ *               | . | . | . | . | . | . | . | . |
+ *                 .   .   .   .   .   .   .   .
+ *                 .   .   .   .   .   .   .   .
+ *
+ *  If offset is more than eight then, byte_stream is incremented by
+ *  offset/8 and offset is taken to be offset modulo 8.
+ */
+extern void bit_stream_init(
+                            bit_stream      *bs,
+                            kal_uint8       *byte_stream,
+                            unsigned int    offset);
+
+/* Read specified number of bits from current position and return it as
+ *  an unsigned integer.
+ *
+ *                                        offset (before)
+ *                                        |
+ *                                        V
+ *                       /-------------------------------\
+ * byte_stream (before)->|   |   |   |   | 1 | 0 | 0 | 0 |
+ *                       |---|---|---|---|---|---|---|---|
+ * byte_stream (after) ->| 1 | 0 |   |   |   |   |   |   |
+ *                       |---|---|---|---|---|---|---|---|
+ *                       | . | . | ^ | . | . | . | . | . |
+ *                                 |
+ *                                 offset (after)
+ *
+ *      On the above stream bit_stream_read(bs, 6) will return 34
+ */
+extern unsigned int bit_stream_read(
+                                    bit_stream      *bs,
+                                    unsigned int    width);
+
+
+/* Write specified number of bits from current position into the
+ * underlying byte stream.
+ *
+ *              bit_stream_write(bs, 6)
+ *
+ *                                        offset (before)
+ *                                        |
+ *                                        V
+ *                       /-------------------------------\
+ * byte_stream (before)->|   |   |   |   | 1 | 0 | 0 | 0 |
+ *                       |---|---|---|---|---|---|---|---|
+ * byte_stream (after) ->| 1 | 0 |   |   |   |   |   |   |
+ *                       |---|---|---|---|---|---|---|---|
+ *                       | . | . | ^ | . | . | . | . | . |
+ *                                 |
+ *                                 offset (after)
+ *
+ */
+extern void bit_stream_write(
+                             bit_stream      *bs,
+                             unsigned int    width,
+                             unsigned int    value );
+
+/* Return the number of bits the internal pointer has moved since
+ * bit_stream_init */
+extern unsigned int bit_stream_cur_pos(bit_stream    *bs);
+
+/* Move pointer back by given number of bits */
+extern void bit_stream_move_back(
+                                 bit_stream      *bs,
+                                 unsigned int    bits);
+
+/* Copy bits from one byte stream to another.
+ * Byte stream is incremented as read operation
+ * is done */
+
+extern void byte_stream_bit_copy(
+                                 kal_uint8      *s,
+                                 unsigned int   s_offset,
+                                 unsigned int   length,
+                                 kal_uint8      *d,
+                                 unsigned int   d_offset);
+
+
+/* Read specified number of bits from the bitstream, starting
+ * from a position, width bits before the current position.
+
+ *
+ *                                        offset (after)
+ *                                        |
+ *                                        V
+ *                       /-------------------------------\
+ * byte_stream (after)-> |   |   |   |   | 1 | 0 | 0 | 0 |
+ *                       |---|---|---|---|---|---|---|---|
+ * byte_stream (before)->| 1 | 0 |   |   |   |   |   |   |
+ *                       |---|---|---|---|---|---|---|---|
+ *                       | . | . | ^ | . | . | . | . | . |
+ *                                 |
+ *                                 offset (before)
+ *
+ *      On the above stream ,
+ *         bit_stream_read_back(bs, 6) will return 34
+ */
+
+extern unsigned int bit_stream_read_back(
+                                         bit_stream    *bs,
+                                         unsigned int  width);
+
+
+
+/* Write specified number of bits to the bitstream starting
+ * from a position width bits before the current position.
+ *
+ *     bit_stream_write_back(bs, 6, 34) will return
+ *
+ *
+ *                                        offset (after)
+ *                                        |
+ *                                        V
+ *                       /-------------------------------\
+ * byte_stream (after) ->|   |   |   |   | 1 | 0 | 0 | 0 |
+ *                       |---|---|---|---|---|---|---|---|
+ * byte_stream (before)->| 1 | 0 |   |   |   |   |   |   |
+ *                       |---|---|---|---|---|---|---|---|
+ *                       | . | . | ^ | . | . | . | . | . |
+ *                                 |
+ *                                 offset (before)
+ *
+ */
+extern void bit_stream_write_back(
+                                  bit_stream      *bs,
+                                  unsigned int    width,
+                                  unsigned int    value );
+#endif /* _BITSTREAM_H */
+