00001 /* 00002 * Copyright (c) 2005, Swedish Institute of Computer Science 00003 * All rights reserved. 00004 * 00005 * Redistribution and use in source and binary forms, with or without 00006 * modification, are permitted provided that the following conditions 00007 * are met: 00008 * 1. Redistributions of source code must retain the above copyright 00009 * notice, this list of conditions and the following disclaimer. 00010 * 2. Redistributions in binary form must reproduce the above copyright 00011 * notice, this list of conditions and the following disclaimer in the 00012 * documentation and/or other materials provided with the distribution. 00013 * 3. Neither the name of the Institute nor the names of its contributors 00014 * may be used to endorse or promote products derived from this software 00015 * without specific prior written permission. 00016 * 00017 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 00018 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 00019 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 00020 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 00021 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 00022 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 00023 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 00024 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 00025 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 00026 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 00027 * SUCH DAMAGE. 00028 * 00029 * This file is part of the Contiki operating system. 00030 * 00031 * @(#)$Id: me.h,v 1.1 2006/06/17 22:41:18 adamdunkels Exp $ 00032 */ 00033 00034 /** \addtogroup lib 00035 @{ */ 00036 00037 /** 00038 * \defgroup me Table-driven Manchester encoding and decoding 00039 * 00040 * Manchester encoding is a bit encoding scheme which translates each 00041 * bit into two bits: the original bit and the inverted bit. 00042 * 00043 * Manchester encoding is used for transmitting ones and zeroes 00044 * between two computers. The Manchester encoding reduces the receive 00045 * oscillator drift by making sure that no consecutive ones or zeroes 00046 * are ever transmitted. 00047 * 00048 * The table driven method of Manchester encoding and decoding uses 00049 * two tables with 256 entries. One table is a direct mapping of an 00050 * 8-bit byte into a 16-bit Manchester encoding of the byte. The 00051 * second table is a mapping of a Manchester encoded 8-bit byte to 4 00052 * decoded bits. 00053 * 00054 * @{ 00055 */ 00056 00057 /** 00058 * \file 00059 * Header file for the table-driven Manchester encoding and decoding 00060 * \author 00061 * Adam Dunkels <adam@sics.se> 00062 * 00063 */ 00064 00065 #ifndef __ME_H__ 00066 #define __ME_H__ 00067 00068 unsigned char me_valid(unsigned char m); 00069 unsigned short me_encode(unsigned char c); 00070 unsigned char me_decode16(unsigned short m); 00071 unsigned char me_decode8(unsigned char m); 00072 00073 #endif /* __ME_H__ */ 00074 00075 /** @} */ 00076 /** @} */