Files
esp-modbus/modbus/mb_objects/functions/mbutils.c
2023-12-10 15:30:06 +01:00

129 lines
4.5 KiB
C

/*
* FreeModbus Libary: A portable Modbus implementation for Modbus ASCII/RTU.
* Copyright (c) 2016, 2017 Nucleron R&D LLC <main@nucleron.ru>
* 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.c, v 1.6 2007/02/18 23:49:07 wolti Exp $
*/
#include <mb_common.h>
#include <mb_proto.h>
/* ----------------------- Defines ------------------------------------------*/
#define BITS_uint8_t 8U
/* ----------------------- Start implementation -----------------------------*/
void mb_util_set_bits(uint8_t *byte_buf, uint16_t bit_offset, uint8_t but_num, uint8_t value)
{
uint16_t word_buf;
uint16_t msk;
uint16_t byte_offset;
uint16_t pre_bits_num;
uint16_t us_val = value;
assert(but_num <= 8);
assert((size_t)BITS_uint8_t == sizeof(uint8_t) * 8);
/* Calculate byte offset for first byte containing the bit values starting
* at bit_offset. */
byte_offset = (uint16_t)((bit_offset) / BITS_uint8_t);
/* How many bits precede our bits to set. */
pre_bits_num = (uint16_t)(bit_offset - byte_offset * BITS_uint8_t);
/* Move bit field into position over bits to set */
us_val <<= pre_bits_num;
/* Prepare a mask for setting the new bits. */
msk = (uint16_t)((1 << (uint16_t) but_num) - 1);
msk <<= bit_offset - byte_offset * BITS_uint8_t;
/* copy bits into temporary storage. */
word_buf = byte_buf[byte_offset];
word_buf |= byte_buf[byte_offset + 1] << BITS_uint8_t;
/* Zero out bit field bits and then or value bits into them. */
word_buf = (uint16_t)((word_buf & (~msk)) | us_val);
/* move bits back into storage */
byte_buf[byte_offset] = (uint8_t)(word_buf & 0xFF);
byte_buf[byte_offset + 1] = (uint8_t)(word_buf >> BITS_uint8_t);
}
uint8_t mb_util_get_bits(uint8_t *byte_buf, uint16_t bit_offset, uint8_t but_num)
{
uint16_t word_buf;
uint16_t msk;
uint16_t byte_offset;
uint16_t pre_bits_num;
/* Calculate byte offset for first byte containing the bit values starting
* at bit_offset. */
byte_offset = (uint16_t)((bit_offset) / BITS_uint8_t);
/* How many bits precede our bits to set. */
pre_bits_num = (uint16_t)(bit_offset - byte_offset * BITS_uint8_t);
/* Prepare a mask for setting the new bits. */
msk = (uint16_t)((1 << (uint16_t) but_num) - 1);
/* copy bits into temporary storage. */
word_buf = byte_buf[byte_offset];
word_buf |= byte_buf[byte_offset + 1] << BITS_uint8_t;
/* throw away unneeded bits. */
word_buf >>= pre_bits_num;
/* mask away bits above the requested bitfield. */
word_buf &= msk;
return (uint8_t) word_buf;
}
mb_exception_t mb_error_to_exception(mb_err_enum_t error_code)
{
mb_exception_t status;
switch (error_code) {
case MB_ENOERR:
status = MB_EX_NONE;
break;
case MB_ENOREG:
status = MB_EX_ILLEGAL_DATA_ADDRESS;
break;
case MB_ETIMEDOUT:
status = MB_EX_SLAVE_BUSY;
break;
default:
status = MB_EX_SLAVE_DEVICE_FAILURE;
break;
}
return status;
}