Tooltron

/* 

 * FreeModbus Libary: A portable Modbus implementation for Modbus ASCII/RTU.

 * Copyright (c) 2006 Christian Walter <wolti@sil.at>

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 3. The name of the author may not be used to endorse or promote products

 *    derived from this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR

 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES

 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.

 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,

 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF

 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 *

 * File: $Id: mbutils.h,v 1.5 2006/12/07 22:10:34 wolti Exp $

 */

#ifndef _MB_UTILS_H

#define _MB_UTILS_H

#ifdef __cplusplus

PR_BEGIN_EXTERN_C

#endif

/*! \defgroup modbus_utils Utilities

 *

 * This module contains some utility functions which can be used by

 * the application. It includes some special functions for working with

 * bitfields backed by a character array buffer.

 *

 */

/*! \addtogroup modbus_utils

 *  @{

 */

/*! \brief Function to set bits in a byte buffer.

 *

 * This function allows the efficient use of an array to implement bitfields.

 * The array used for storing the bits must always be a multiple of two

 * bytes. Up to eight bits can be set or cleared in one operation.

 *

 * \param ucByteBuf A buffer where the bit values are stored. Must be a

 *   multiple of 2 bytes. No length checking is performed and if

 *   usBitOffset / 8 is greater than the size of the buffer memory contents

 *   is overwritten.

 * \param usBitOffset The starting address of the bits to set. The first

 *   bit has the offset 0.

 * \param ucNBits Number of bits to modify. The value must always be smaller

 *   than 8.

 * \param ucValues Thew new values for the bits. The value for the first bit

 *   starting at <code>usBitOffset</code> is the LSB of the value

 *   <code>ucValues</code>

 *

 * \code

 * ucBits[2] = {0, 0};

 *

 * // Set bit 4 to 1 (read: set 1 bit starting at bit offset 4 to value 1)

 * xMBUtilSetBits( ucBits, 4, 1, 1 );

 *

 * // Set bit 7 to 1 and bit 8 to 0.

 * xMBUtilSetBits( ucBits, 7, 2, 0x01 );

 *

 * // Set bits 8 - 11 to 0x05 and bits 12 - 15 to 0x0A;

 * xMBUtilSetBits( ucBits, 8, 8, 0x5A);

 * \endcode

 */

void            xMBUtilSetBits( UCHAR * ucByteBuf, USHORT usBitOffset,

                                UCHAR ucNBits, UCHAR ucValues );

/*! \brief Function to read bits in a byte buffer.

 *

 * This function is used to extract up bit values from an array. Up to eight

 * bit values can be extracted in one step.

 *

 * \param ucByteBuf A buffer where the bit values are stored.

 * \param usBitOffset The starting address of the bits to set. The first

 *   bit has the offset 0.

 * \param ucNBits Number of bits to modify. The value must always be smaller

 *   than 8.

 *

 * \code

 * UCHAR ucBits[2] = {0, 0};

 * UCHAR ucResult;

 *

 * // Extract the bits 3 - 10.

 * ucResult = xMBUtilGetBits( ucBits, 3, 8 );

 * \endcode

 */

UCHAR           xMBUtilGetBits( UCHAR * ucByteBuf, USHORT usBitOffset,

                                UCHAR ucNBits );

/*! @} */

#ifdef __cplusplus

PR_END_EXTERN_C

#endif

#endif