/** * NEURON IIoT System for Industry 4.0 * Copyright (C) 2020-2022 EMQ Technologies Co., Ltd All rights reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 3 of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this program; if not, write to the Free Software Foundation, * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. **/ #include #include #include #include "modbus.h" static uint16_t calcrc(uint8_t *buf, int len) { const uint16_t table[256] = { 0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241, 0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440, 0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40, 0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841, 0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40, 0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41, 0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641, 0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040, 0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240, 0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441, 0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41, 0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840, 0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41, 0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40, 0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640, 0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041, 0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240, 0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441, 0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41, 0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840, 0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41, 0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40, 0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640, 0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041, 0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241, 0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440, 0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40, 0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841, 0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40, 0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41, 0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641, 0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040 }; uint16_t crc = 0xffff; for (int i = 0; i < len; i++) { crc = (crc >> 8) ^ table[(crc ^ buf[i]) & 0xFF]; } return crc; } void modbus_header_wrap(neu_protocol_pack_buf_t *buf, uint16_t seq) { assert(neu_protocol_pack_buf_unused_size(buf) >= sizeof(struct modbus_header)); struct modbus_header *header = (struct modbus_header *) neu_protocol_pack_buf( buf, sizeof(struct modbus_header)); header->seq = htons(seq); header->protocol = 0x0; header->len = htons(neu_protocol_pack_buf_used_size(buf) - sizeof(struct modbus_header)); } int modbus_header_unwrap(neu_protocol_unpack_buf_t *buf, struct modbus_header * out_header) { struct modbus_header *header = (struct modbus_header *) neu_protocol_unpack_buf( buf, sizeof(struct modbus_header)); if (header == NULL || ntohs(header->len) > neu_protocol_unpack_buf_unused_size(buf)) { return 0; } if (header->protocol != 0x0) { return -1; } *out_header = *header; out_header->len = ntohs(out_header->len); out_header->seq = ntohs(out_header->seq); return sizeof(struct modbus_header); } void modbus_code_wrap(neu_protocol_pack_buf_t *buf, uint8_t slave_id, uint8_t function) { assert(neu_protocol_pack_buf_unused_size(buf) >= sizeof(struct modbus_code)); struct modbus_code *code = (struct modbus_code *) neu_protocol_pack_buf( buf, sizeof(struct modbus_code)); code->slave_id = slave_id; code->function = function; } int modbus_code_unwrap(neu_protocol_unpack_buf_t *buf, struct modbus_code * out_code) { struct modbus_code *code = (struct modbus_code *) neu_protocol_unpack_buf( buf, sizeof(struct modbus_code)); if (code == NULL) { return 0; } *out_code = *code; return sizeof(struct modbus_code); } void modbus_address_wrap(neu_protocol_pack_buf_t *buf, uint16_t start, uint16_t n_register, enum modbus_action action) { if (action == MODBUS_ACTION_HOLD_REG_WRITE && n_register == 1) { assert(neu_protocol_pack_buf_unused_size(buf) >= sizeof(start)); uint16_t *address = (uint16_t *) neu_protocol_pack_buf(buf, sizeof(start)); *address = htons(start); } else { assert(neu_protocol_pack_buf_unused_size(buf) >= sizeof(struct modbus_address)); struct modbus_address *address = (struct modbus_address *) neu_protocol_pack_buf( buf, sizeof(struct modbus_address)); address->start_address = htons(start); address->n_reg = htons(n_register); } } int modbus_address_unwrap(neu_protocol_unpack_buf_t *buf, struct modbus_address * out_address) { struct modbus_address *address = (struct modbus_address *) neu_protocol_unpack_buf( buf, sizeof(struct modbus_address)); if (address == NULL) { return 0; } *out_address = *address; out_address->start_address = ntohs(out_address->start_address); out_address->n_reg = ntohs(out_address->n_reg); return sizeof(struct modbus_address); } void modbus_data_wrap(neu_protocol_pack_buf_t *buf, uint8_t n_byte, uint8_t *bytes, enum modbus_action action) { assert(neu_protocol_pack_buf_unused_size(buf) >= sizeof(struct modbus_data) + n_byte); uint8_t *data = neu_protocol_pack_buf(buf, n_byte); memcpy(data, bytes, n_byte); if (action == MODBUS_ACTION_DEFAULT || n_byte > 2) { struct modbus_data *mdata = (struct modbus_data *) neu_protocol_pack_buf( buf, sizeof(struct modbus_data)); mdata->n_byte = n_byte; } } int modbus_data_unwrap(neu_protocol_unpack_buf_t *buf, struct modbus_data * out_data) { struct modbus_data *mdata = (struct modbus_data *) neu_protocol_unpack_buf( buf, sizeof(struct modbus_data)); if (mdata == NULL || mdata->n_byte > neu_protocol_unpack_buf_unused_size(buf)) { return 0; } *out_data = *mdata; return sizeof(struct modbus_data); } void modbus_crc_set(neu_protocol_pack_buf_t *buf) { uint16_t crc = calcrc(neu_protocol_pack_buf_get(buf), neu_protocol_pack_buf_used_size(buf) - 2); uint16_t *p_crc = (uint16_t *) neu_protocol_pack_buf_set( buf, neu_protocol_pack_buf_used_size(buf) - 2, 2); *p_crc = crc; } void modbus_crc_wrap(neu_protocol_pack_buf_t *buf) { assert(neu_protocol_pack_buf_unused_size(buf) >= sizeof(struct modbus_crc)); struct modbus_crc *crc = (struct modbus_crc *) neu_protocol_pack_buf( buf, sizeof(struct modbus_crc)); crc->crc = 0; } int modbus_crc_unwrap(neu_protocol_unpack_buf_t *buf, struct modbus_crc * out_crc) { struct modbus_crc *crc = (struct modbus_crc *) neu_protocol_unpack_buf( buf, sizeof(struct modbus_crc)); if (crc == NULL) { return 0; } *out_crc = *crc; return sizeof(struct modbus_crc); } const char *modbus_area_to_str(modbus_area_e area) { switch (area) { case MODBUS_AREA_COIL: return "coil"; case MODBUS_AREA_INPUT: return "input"; case MODBUS_AREA_INPUT_REGISTER: return "input register"; case MODBUS_AREA_HOLD_REGISTER: return "hold register"; default: return "unknown area"; } }