/* * FreeModbus Libary: A portable Modbus implementation for Modbus ASCII/RTU. * Copyright (c) 2016, 2017 Nucleron R&D LLC * Copyright (c) 2006 Christian Walter * 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: mbfunccoils.c, v 1.8 2007/02/18 23:47:16 wolti Exp $ */ #include #include #include "mb_slave.h" /* ----------------------- Defines ------------------------------------------*/ #define MB_PDU_FUNC_READ_ADDR_OFF (MB_PDU_DATA_OFF) #define MB_PDU_FUNC_READ_COILCNT_OFF (MB_PDU_DATA_OFF + 2) #define MB_PDU_FUNC_READ_SIZE (4) #define MB_PDU_FUNC_READ_COILCNT_MAX (0x07D0) #define MB_PDU_FUNC_WRITE_ADDR_OFF (MB_PDU_DATA_OFF) #define MB_PDU_FUNC_WRITE_VALUE_OFF (MB_PDU_DATA_OFF + 2) #define MB_PDU_FUNC_WRITE_SIZE (4) #define MB_PDU_FUNC_WRITE_MUL_ADDR_OFF (MB_PDU_DATA_OFF) #define MB_PDU_FUNC_WRITE_MUL_COILCNT_OFF (MB_PDU_DATA_OFF + 2) #define MB_PDU_FUNC_WRITE_MUL_BYTECNT_OFF (MB_PDU_DATA_OFF + 4) #define MB_PDU_FUNC_WRITE_MUL_VALUES_OFF (MB_PDU_DATA_OFF + 5) #define MB_PDU_FUNC_WRITE_MUL_SIZE_MIN (5) #define MB_PDU_FUNC_WRITE_MUL_COILCNT_MAX (0x07B0) /* ----------------------- Static functions ---------------------------------*/ mb_exception_t mb_error_to_exception(mb_err_enum_t error_code); /* ----------------------- Start implementation -----------------------------*/ #if MB_FUNC_READ_COILS_ENABLED > 0 mb_exception_t mbs_fn_read_coils(mb_base_t *inst, uint8_t *frame_ptr, uint16_t *len_buf) { uint16_t reg_addr; uint16_t coil_cnt; uint8_t byte_num; uint8_t *frame_cur; mb_exception_t status = MB_EX_NONE; mb_err_enum_t reg_status = MB_EILLFUNC; if (*len_buf == (MB_PDU_FUNC_READ_SIZE + MB_PDU_SIZE_MIN)) { reg_addr = (uint16_t)(frame_ptr[MB_PDU_FUNC_READ_ADDR_OFF] << 8); reg_addr |= (uint16_t)(frame_ptr[MB_PDU_FUNC_READ_ADDR_OFF + 1]); reg_addr++; coil_cnt = (uint16_t)(frame_ptr[MB_PDU_FUNC_READ_COILCNT_OFF] << 8); coil_cnt |= (uint16_t)(frame_ptr[MB_PDU_FUNC_READ_COILCNT_OFF + 1]); /* Check if the number of registers to read is valid. If not * return Modbus illegal data value exception. */ if ((coil_cnt >= 1) && (coil_cnt < MB_PDU_FUNC_READ_COILCNT_MAX)) { /* Set the current PDU data pointer to the beginning. */ frame_cur = &frame_ptr[MB_PDU_FUNC_OFF]; *len_buf = MB_PDU_FUNC_OFF; /* First byte contains the function code. */ *frame_cur++ = MB_FUNC_READ_COILS; *len_buf += 1; /* Test if the quantity of coils is a multiple of 8. If not last * byte is only partially field with unused coils set to zero. */ if ((coil_cnt & 0x0007) != 0) { byte_num = (uint8_t)(coil_cnt / 8 + 1); } else { byte_num = (uint8_t)(coil_cnt / 8); } *frame_cur++ = byte_num; *len_buf += 1; if (inst->rw_cbs.reg_coils_cb) { reg_status = inst->rw_cbs.reg_coils_cb(inst, frame_cur, reg_addr, coil_cnt, MB_REG_READ); } /* If an error occured convert it into a Modbus exception. */ if (reg_status != MB_ENOERR) { status = mb_error_to_exception(reg_status); } else { /* The response contains the function code, the starting address * and the quantity of registers. We reuse the old values in the * buffer because they are still valid. */ *len_buf += byte_num;; } } else { status = MB_EX_ILLEGAL_DATA_VALUE; } } else { /* Can't be a valid read coil register request because the length * is incorrect. */ status = MB_EX_ILLEGAL_DATA_VALUE; } return status; } #if MB_FUNC_WRITE_COIL_ENABLED > 0 mb_exception_t mbs_fn_write_coil(mb_base_t *inst, uint8_t *frame_ptr, uint16_t *len_buf) { uint16_t reg_addr; uint8_t buf[2]; mb_exception_t status = MB_EX_NONE; mb_err_enum_t reg_status = MB_EILLFUNC; if (*len_buf == (MB_PDU_FUNC_WRITE_SIZE + MB_PDU_SIZE_MIN)) { reg_addr = (uint16_t)(frame_ptr[MB_PDU_FUNC_WRITE_ADDR_OFF] << 8); reg_addr |= (uint16_t)(frame_ptr[MB_PDU_FUNC_WRITE_ADDR_OFF + 1]); reg_addr++; if ((frame_ptr[MB_PDU_FUNC_WRITE_VALUE_OFF + 1] == 0x00) && ((frame_ptr[MB_PDU_FUNC_WRITE_VALUE_OFF] == 0xFF) || (frame_ptr[MB_PDU_FUNC_WRITE_VALUE_OFF] == 0x00))) { buf[1] = 0; if (frame_ptr[MB_PDU_FUNC_WRITE_VALUE_OFF] == 0xFF) { buf[0] = 1; } else { buf[0] = 0; } if (inst->rw_cbs.reg_coils_cb) { reg_status = inst->rw_cbs.reg_coils_cb(inst, &buf[0], reg_addr, 1, MB_REG_WRITE); } /* If an error occured convert it into a Modbus exception. */ if (reg_status != MB_ENOERR) { status = mb_error_to_exception(reg_status); } } else { status = MB_EX_ILLEGAL_DATA_VALUE; } } else { /* Can't be a valid write coil register request because the length * is incorrect. */ status = MB_EX_ILLEGAL_DATA_VALUE; } return status; } #endif #if MB_FUNC_WRITE_MULTIPLE_COILS_ENABLED > 0 mb_exception_t mbs_fn_write_multi_coils(mb_base_t *inst, uint8_t *frame_ptr, uint16_t *len_buf) { uint16_t reg_addr; uint16_t coil_cnt; uint8_t byte_cnt; uint8_t byte_cnt_verify; mb_exception_t status = MB_EX_NONE; mb_err_enum_t reg_status = MB_EILLFUNC; if (*len_buf > (MB_PDU_FUNC_WRITE_SIZE + MB_PDU_SIZE_MIN)) { reg_addr = (uint16_t)(frame_ptr[MB_PDU_FUNC_WRITE_MUL_ADDR_OFF] << 8); reg_addr |= (uint16_t)(frame_ptr[MB_PDU_FUNC_WRITE_MUL_ADDR_OFF + 1]); reg_addr++; coil_cnt = (uint16_t)(frame_ptr[MB_PDU_FUNC_WRITE_MUL_COILCNT_OFF] << 8); coil_cnt |= (uint16_t)(frame_ptr[MB_PDU_FUNC_WRITE_MUL_COILCNT_OFF + 1]); byte_cnt = frame_ptr[MB_PDU_FUNC_WRITE_MUL_BYTECNT_OFF]; /* Compute the number of expected bytes in the request. */ if ((coil_cnt & 0x0007) != 0) { byte_cnt_verify = (uint8_t)(coil_cnt / 8 + 1); } else { byte_cnt_verify = (uint8_t)(coil_cnt / 8); } if ((coil_cnt >= 1) && (coil_cnt <= MB_PDU_FUNC_WRITE_MUL_COILCNT_MAX) && (byte_cnt_verify == byte_cnt)) { if (inst->rw_cbs.reg_coils_cb) { reg_status = inst->rw_cbs.reg_coils_cb(inst, &frame_ptr[MB_PDU_FUNC_WRITE_MUL_VALUES_OFF], reg_addr, coil_cnt, MB_REG_WRITE); } /* If an error occured convert it into a Modbus exception. */ if (reg_status != MB_ENOERR) { status = mb_error_to_exception(reg_status); } else { /* The response contains the function code, the starting address * and the quantity of registers. We reuse the old values in the * buffer because they are still valid. */ *len_buf = MB_PDU_FUNC_WRITE_MUL_BYTECNT_OFF; } } else { status = MB_EX_ILLEGAL_DATA_VALUE; } } else { /* Can't be a valid write coil register request because the length * is incorrect. */ status = MB_EX_ILLEGAL_DATA_VALUE; } return status; } #endif #endif