1 | /* |
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2 | * Copyright © 2001-2008 Stéphane Raimbault <stephane.raimbault@gmail.com> |
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3 | * |
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4 | * This program is free software: you can redistribute it and/or modify |
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5 | * it under the terms of the GNU Lesser Public License as published by |
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6 | * the Free Software Foundation; either version 3 of the License, or |
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7 | * (at your option) any later version. |
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8 | * |
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9 | * This program is distributed in the hope that it will be useful, |
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10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
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11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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12 | * GNU Lesser Public License for more details. |
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13 | * |
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14 | * You should have received a copy of the GNU Lesser Public License |
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15 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
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16 | */ |
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17 | |
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18 | /* |
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19 | The library is designed to send and receive data from a device that |
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20 | communicate via the Modbus protocol. |
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21 | |
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22 | The function names used are inspired by the Modicon Modbus Protocol |
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23 | Reference Guide which can be obtained from Schneider at |
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24 | www.schneiderautomation.com. |
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25 | |
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26 | Documentation: |
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27 | http://www.easysw.com/~mike/serial/serial.html |
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28 | http://copyleft.free.fr/wordpress/index.php/libmodbus/ |
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29 | */ |
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30 | |
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31 | #include <stdio.h> |
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32 | #include <string.h> |
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33 | #include <stdlib.h> |
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34 | #include <stdint.h> |
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35 | #include <termios.h> |
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36 | #include <sys/time.h> |
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37 | #include <unistd.h> |
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38 | #include <errno.h> |
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39 | #include <limits.h> |
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40 | #include <fcntl.h> |
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41 | |
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42 | /* TCP */ |
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43 | #include <sys/types.h> |
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44 | #include <sys/socket.h> |
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45 | #include <sys/ioctl.h> |
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46 | #include <netinet/in.h> |
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47 | #include <netinet/ip.h> |
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48 | #include <netinet/tcp.h> |
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49 | #include <arpa/inet.h> |
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50 | |
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51 | #include "modbus.h" |
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52 | |
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53 | #define UNKNOWN_ERROR_MSG "Not defined in modbus specification" |
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54 | |
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55 | /* This structure reduces the number of params in functions and so |
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56 | * optimizes the speed of execution (~ 37%). */ |
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57 | typedef struct { |
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58 | int slave; |
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59 | int function; |
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60 | int t_id; |
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61 | } sft_t; |
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62 | |
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63 | static const uint8_t NB_TAB_ERROR_MSG = 12; |
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64 | static const char *TAB_ERROR_MSG[] = { |
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65 | /* 0x00 */ UNKNOWN_ERROR_MSG, |
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66 | /* 0x01 */ "Illegal function code", |
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67 | /* 0x02 */ "Illegal data address", |
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68 | /* 0x03 */ "Illegal data value", |
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69 | /* 0x04 */ "Slave device or server failure", |
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70 | /* 0x05 */ "Acknowledge", |
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71 | /* 0x06 */ "Slave device or server busy", |
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72 | /* 0x07 */ "Negative acknowledge", |
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73 | /* 0x08 */ "Memory parity error", |
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74 | /* 0x09 */ UNKNOWN_ERROR_MSG, |
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75 | /* 0x0A */ "Gateway path unavailable", |
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76 | /* 0x0B */ "Target device failed to respond" |
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77 | }; |
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78 | |
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79 | /* Table of CRC values for high-order byte */ |
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80 | static uint8_t table_crc_hi[] = { |
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81 | 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, |
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82 | 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, |
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83 | 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, |
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84 | 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, |
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85 | 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, |
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86 | 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, |
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87 | 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, |
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88 | 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, |
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89 | 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, |
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90 | 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, |
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91 | 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, |
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92 | 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, |
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93 | 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, |
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94 | 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, |
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95 | 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, |
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96 | 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, |
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97 | 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, |
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98 | 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, |
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99 | 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, |
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100 | 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, |
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101 | 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, |
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102 | 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, |
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103 | 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, |
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104 | 0x81, 0x40, 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, |
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105 | 0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41, 0x01, 0xC0, |
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106 | 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40 |
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107 | }; |
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108 | |
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109 | /* Table of CRC values for low-order byte */ |
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110 | static uint8_t table_crc_lo[] = { |
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111 | 0x00, 0xC0, 0xC1, 0x01, 0xC3, 0x03, 0x02, 0xC2, 0xC6, 0x06, |
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112 | 0x07, 0xC7, 0x05, 0xC5, 0xC4, 0x04, 0xCC, 0x0C, 0x0D, 0xCD, |
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113 | 0x0F, 0xCF, 0xCE, 0x0E, 0x0A, 0xCA, 0xCB, 0x0B, 0xC9, 0x09, |
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114 | 0x08, 0xC8, 0xD8, 0x18, 0x19, 0xD9, 0x1B, 0xDB, 0xDA, 0x1A, |
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115 | 0x1E, 0xDE, 0xDF, 0x1F, 0xDD, 0x1D, 0x1C, 0xDC, 0x14, 0xD4, |
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116 | 0xD5, 0x15, 0xD7, 0x17, 0x16, 0xD6, 0xD2, 0x12, 0x13, 0xD3, |
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117 | 0x11, 0xD1, 0xD0, 0x10, 0xF0, 0x30, 0x31, 0xF1, 0x33, 0xF3, |
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118 | 0xF2, 0x32, 0x36, 0xF6, 0xF7, 0x37, 0xF5, 0x35, 0x34, 0xF4, |
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119 | 0x3C, 0xFC, 0xFD, 0x3D, 0xFF, 0x3F, 0x3E, 0xFE, 0xFA, 0x3A, |
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120 | 0x3B, 0xFB, 0x39, 0xF9, 0xF8, 0x38, 0x28, 0xE8, 0xE9, 0x29, |
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121 | 0xEB, 0x2B, 0x2A, 0xEA, 0xEE, 0x2E, 0x2F, 0xEF, 0x2D, 0xED, |
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122 | 0xEC, 0x2C, 0xE4, 0x24, 0x25, 0xE5, 0x27, 0xE7, 0xE6, 0x26, |
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123 | 0x22, 0xE2, 0xE3, 0x23, 0xE1, 0x21, 0x20, 0xE0, 0xA0, 0x60, |
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124 | 0x61, 0xA1, 0x63, 0xA3, 0xA2, 0x62, 0x66, 0xA6, 0xA7, 0x67, |
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125 | 0xA5, 0x65, 0x64, 0xA4, 0x6C, 0xAC, 0xAD, 0x6D, 0xAF, 0x6F, |
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126 | 0x6E, 0xAE, 0xAA, 0x6A, 0x6B, 0xAB, 0x69, 0xA9, 0xA8, 0x68, |
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127 | 0x78, 0xB8, 0xB9, 0x79, 0xBB, 0x7B, 0x7A, 0xBA, 0xBE, 0x7E, |
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128 | 0x7F, 0xBF, 0x7D, 0xBD, 0xBC, 0x7C, 0xB4, 0x74, 0x75, 0xB5, |
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129 | 0x77, 0xB7, 0xB6, 0x76, 0x72, 0xB2, 0xB3, 0x73, 0xB1, 0x71, |
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130 | 0x70, 0xB0, 0x50, 0x90, 0x91, 0x51, 0x93, 0x53, 0x52, 0x92, |
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131 | 0x96, 0x56, 0x57, 0x97, 0x55, 0x95, 0x94, 0x54, 0x9C, 0x5C, |
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132 | 0x5D, 0x9D, 0x5F, 0x9F, 0x9E, 0x5E, 0x5A, 0x9A, 0x9B, 0x5B, |
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133 | 0x99, 0x59, 0x58, 0x98, 0x88, 0x48, 0x49, 0x89, 0x4B, 0x8B, |
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134 | 0x8A, 0x4A, 0x4E, 0x8E, 0x8F, 0x4F, 0x8D, 0x4D, 0x4C, 0x8C, |
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135 | 0x44, 0x84, 0x85, 0x45, 0x87, 0x47, 0x46, 0x86, 0x82, 0x42, |
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136 | 0x43, 0x83, 0x41, 0x81, 0x80, 0x40 |
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137 | }; |
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138 | |
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139 | /* Treats errors and flush or close connection if necessary */ |
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140 | static void error_treat(modbus_param_t *mb_param, int code, const char *string) |
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141 | { |
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142 | printf("\nERROR %s (%d)\n", string, code); |
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143 | |
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144 | if (mb_param->error_handling == FLUSH_OR_RECONNECT_ON_ERROR) { |
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145 | switch (code) { |
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146 | case ILLEGAL_DATA_VALUE: |
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147 | case ILLEGAL_DATA_ADDRESS: |
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148 | case ILLEGAL_FUNCTION: |
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149 | break; |
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150 | default: |
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151 | if (mb_param->type_com == RTU) { |
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152 | tcflush(mb_param->fd, TCIOFLUSH); |
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153 | } else { |
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154 | modbus_close(mb_param); |
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155 | modbus_connect(mb_param); |
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156 | } |
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157 | } |
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158 | } |
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159 | } |
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160 | |
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161 | /* Computes the length of the expected response */ |
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162 | static unsigned int compute_response_length(modbus_param_t *mb_param, |
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163 | uint8_t *query) |
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164 | { |
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165 | int resp_length; |
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166 | int offset; |
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167 | |
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168 | offset = mb_param->header_length; |
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169 | |
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170 | switch (query[offset + 1]) { |
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171 | case FC_READ_COIL_STATUS: |
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172 | case FC_READ_INPUT_STATUS: { |
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173 | /* Header + nb values (code from force_multiple_coils) */ |
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174 | int nb = (query[offset + 4] << 8) | query[offset + 5]; |
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175 | resp_length = 3 + (nb / 8) + ((nb % 8) ? 1 : 0); |
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176 | } |
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177 | break; |
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178 | case FC_READ_HOLDING_REGISTERS: |
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179 | case FC_READ_INPUT_REGISTERS: |
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180 | /* Header + 2 * nb values */ |
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181 | resp_length = 3 + 2 * (query[offset + 4] << 8 | |
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182 | query[offset + 5]); |
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183 | break; |
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184 | case FC_READ_EXCEPTION_STATUS: |
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185 | resp_length = 4; |
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186 | break; |
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187 | default: |
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188 | resp_length = 6; |
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189 | } |
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190 | |
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191 | resp_length += offset + mb_param->checksum_length; |
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192 | |
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193 | return resp_length; |
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194 | } |
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195 | |
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196 | /* Builds a RTU query header */ |
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197 | static int build_query_basis_rtu(int slave, int function, |
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198 | int start_addr, int nb, |
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199 | uint8_t *query) |
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200 | { |
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201 | query[0] = slave; |
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202 | query[1] = function; |
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203 | query[2] = start_addr >> 8; |
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204 | query[3] = start_addr & 0x00ff; |
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205 | query[4] = nb >> 8; |
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206 | query[5] = nb & 0x00ff; |
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207 | |
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208 | return PRESET_QUERY_LENGTH_RTU; |
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209 | } |
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210 | |
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211 | /* Builds a TCP query header */ |
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212 | static int build_query_basis_tcp(int slave, int function, |
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213 | int start_addr, int nb, |
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214 | uint8_t *query) |
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215 | { |
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216 | |
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217 | /* Extract from MODBUS Messaging on TCP/IP Implementation |
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218 | Guide V1.0b (page 23/46): |
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219 | The transaction identifier is used to associate the future |
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220 | response with the request. So, at a time, on a TCP |
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221 | connection, this identifier must be unique. |
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222 | */ |
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223 | static uint16_t t_id = 0; |
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224 | |
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225 | /* Transaction ID */ |
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226 | if (t_id < UINT16_MAX) |
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227 | t_id++; |
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228 | else |
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229 | t_id = 0; |
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230 | query[0] = t_id >> 8; |
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231 | query[1] = t_id & 0x00ff; |
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232 | |
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233 | /* Protocol Modbus */ |
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234 | query[2] = 0; |
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235 | query[3] = 0; |
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236 | |
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237 | /* Length to fix later with set_query_length_tcp (4 and 5) */ |
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238 | |
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239 | query[6] = slave; |
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240 | query[7] = function; |
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241 | query[8] = start_addr >> 8; |
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242 | query[9] = start_addr & 0x00ff; |
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243 | query[10] = nb >> 8; |
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244 | query[11] = nb & 0x00ff; |
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245 | |
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246 | return PRESET_QUERY_LENGTH_TCP; |
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247 | } |
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248 | |
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249 | static int build_query_basis(modbus_param_t *mb_param, int slave, |
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250 | int function, int start_addr, |
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251 | int nb, uint8_t *query) |
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252 | { |
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253 | if (mb_param->type_com == RTU) |
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254 | return build_query_basis_rtu(slave, function, start_addr, |
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255 | nb, query); |
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256 | else |
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257 | return build_query_basis_tcp(slave, function, start_addr, |
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258 | nb, query); |
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259 | } |
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260 | |
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261 | /* Builds a RTU response header */ |
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262 | static int build_response_basis_rtu(sft_t *sft, uint8_t *response) |
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263 | { |
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264 | response[0] = sft->slave; |
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265 | response[1] = sft->function; |
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266 | |
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267 | return PRESET_RESPONSE_LENGTH_RTU; |
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268 | } |
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269 | |
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270 | /* Builds a TCP response header */ |
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271 | static int build_response_basis_tcp(sft_t *sft, uint8_t *response) |
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272 | { |
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273 | /* Extract from MODBUS Messaging on TCP/IP Implementation |
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274 | Guide V1.0b (page 23/46): |
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275 | The transaction identifier is used to associate the future |
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276 | response with the request. */ |
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277 | response[0] = sft->t_id >> 8; |
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278 | response[1] = sft->t_id & 0x00ff; |
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279 | |
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280 | /* Protocol Modbus */ |
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281 | response[2] = 0; |
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282 | response[3] = 0; |
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283 | |
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284 | /* Length to fix later with set_message_length_tcp (4 and 5) */ |
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285 | |
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286 | response[6] = sft->slave; |
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287 | response[7] = sft->function; |
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288 | |
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289 | return PRESET_RESPONSE_LENGTH_TCP; |
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290 | } |
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291 | |
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292 | static int build_response_basis(modbus_param_t *mb_param, sft_t *sft, |
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293 | uint8_t *response) |
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294 | { |
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295 | if (mb_param->type_com == RTU) |
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296 | return build_response_basis_rtu(sft, response); |
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297 | else |
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298 | return build_response_basis_tcp(sft, response); |
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299 | } |
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300 | |
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301 | /* Sets the length of TCP message in the message (query and response) */ |
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302 | void set_message_length_tcp(uint8_t *msg, int msg_length) |
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303 | { |
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304 | /* Substract the header length to the message length */ |
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305 | int mbap_length = msg_length - 6; |
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306 | |
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307 | msg[4] = mbap_length >> 8; |
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308 | msg[5] = mbap_length & 0x00FF; |
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309 | } |
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310 | |
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311 | /* Fast CRC */ |
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312 | static uint16_t crc16(uint8_t *buffer, uint16_t buffer_length) |
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313 | { |
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314 | uint8_t crc_hi = 0xFF; /* high CRC byte initialized */ |
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315 | uint8_t crc_lo = 0xFF; /* low CRC byte initialized */ |
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316 | unsigned int i; /* will index into CRC lookup */ |
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317 | |
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318 | /* pass through message buffer */ |
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319 | while (buffer_length--) { |
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320 | i = crc_hi ^ *buffer++; /* calculate the CRC */ |
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321 | crc_hi = crc_lo ^ table_crc_hi[i]; |
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322 | crc_lo = table_crc_lo[i]; |
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323 | } |
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324 | |
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325 | return (crc_hi << 8 | crc_lo); |
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326 | } |
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327 | |
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328 | /* If CRC is correct returns 0 else returns INVALID_CRC */ |
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329 | static int check_crc16(modbus_param_t *mb_param, |
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330 | uint8_t *msg, |
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331 | const int msg_length) |
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332 | { |
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333 | int ret; |
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334 | uint16_t crc_calc; |
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335 | uint16_t crc_received; |
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336 | |
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337 | crc_calc = crc16(msg, msg_length - 2); |
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338 | crc_received = (msg[msg_length - 2] << 8) | msg[msg_length - 1]; |
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339 | |
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340 | /* Check CRC of msg */ |
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341 | if (crc_calc == crc_received) { |
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342 | ret = 0; |
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343 | } else { |
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344 | char s_error[64]; |
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345 | sprintf(s_error, |
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346 | "invalid crc received %0X - crc_calc %0X", |
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347 | crc_received, crc_calc); |
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348 | ret = INVALID_CRC; |
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349 | error_treat(mb_param, ret, s_error); |
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350 | } |
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351 | |
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352 | return ret; |
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353 | } |
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354 | |
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355 | /* Sends a query/response over a serial or a TCP communication */ |
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356 | static int modbus_send(modbus_param_t *mb_param, uint8_t *query, |
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357 | int query_length) |
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358 | { |
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359 | int ret; |
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360 | uint16_t s_crc; |
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361 | int i; |
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362 | |
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363 | if (mb_param->type_com == RTU) { |
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364 | s_crc = crc16(query, query_length); |
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365 | query[query_length++] = s_crc >> 8; |
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366 | query[query_length++] = s_crc & 0x00FF; |
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367 | } else { |
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368 | set_message_length_tcp(query, query_length); |
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369 | } |
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370 | |
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371 | if (mb_param->debug) { |
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372 | for (i = 0; i < query_length; i++) |
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373 | printf("[%.2X]", query[i]); |
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374 | printf("\n"); |
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375 | } |
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376 | |
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377 | if (mb_param->saveRawData) |
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378 | { |
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379 | for (i = 0; i < query_length; i++) |
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380 | mb_param->rawQuery[i]=query[i]; |
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381 | mb_param->rawQueryLength=query_length; |
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382 | } |
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383 | |
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384 | if (mb_param->type_com == RTU) |
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385 | ret = write(mb_param->fd, query, query_length); |
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386 | else |
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387 | ret = send(mb_param->fd, query, query_length, 0); |
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388 | |
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389 | /* Return the number of bytes written (0 to n) |
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390 | or PORT_SOCKET_FAILURE on error */ |
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391 | if ((ret == -1) || (ret != query_length)) { |
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392 | ret = PORT_SOCKET_FAILURE; |
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393 | error_treat(mb_param, ret, "Write port/socket failure"); |
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394 | } |
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395 | |
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396 | return ret; |
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397 | } |
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398 | |
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399 | /* Computes the length of the header following the function code */ |
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400 | static uint8_t compute_query_length_header(int function) |
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401 | { |
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402 | int length; |
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403 | |
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404 | if (function <= FC_FORCE_SINGLE_COIL || |
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405 | function == FC_PRESET_SINGLE_REGISTER) |
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406 | /* Read and single write */ |
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407 | length = 4; |
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408 | else if (function == FC_FORCE_MULTIPLE_COILS || |
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409 | function == FC_PRESET_MULTIPLE_REGISTERS) |
---|
410 | /* Multiple write */ |
---|
411 | length = 5; |
---|
412 | else |
---|
413 | length = 0; |
---|
414 | |
---|
415 | return length; |
---|
416 | } |
---|
417 | |
---|
418 | /* Computes the length of the data to write in the query */ |
---|
419 | static int compute_query_length_data(modbus_param_t *mb_param, uint8_t *msg) |
---|
420 | { |
---|
421 | int function = msg[mb_param->header_length + 1]; |
---|
422 | int length; |
---|
423 | |
---|
424 | if (function == FC_FORCE_MULTIPLE_COILS || |
---|
425 | function == FC_PRESET_MULTIPLE_REGISTERS) |
---|
426 | length = msg[mb_param->header_length + 6]; |
---|
427 | else |
---|
428 | length = 0; |
---|
429 | |
---|
430 | length += mb_param->checksum_length; |
---|
431 | |
---|
432 | return length; |
---|
433 | } |
---|
434 | |
---|
435 | #define WAIT_DATA() \ |
---|
436 | { \ |
---|
437 | while ((select_ret = select(mb_param->fd+1, &rfds, NULL, NULL, &tv)) == -1) { \ |
---|
438 | if (errno == EINTR) { \ |
---|
439 | printf("A non blocked signal was caught\n"); \ |
---|
440 | /* Necessary after an error */ \ |
---|
441 | FD_ZERO(&rfds); \ |
---|
442 | FD_SET(mb_param->fd, &rfds); \ |
---|
443 | } else { \ |
---|
444 | error_treat(mb_param, SELECT_FAILURE, "Select failure"); \ |
---|
445 | return SELECT_FAILURE; \ |
---|
446 | } \ |
---|
447 | } \ |
---|
448 | \ |
---|
449 | if (select_ret == 0) { \ |
---|
450 | /* Call to error_treat is done later to manage exceptions */ \ |
---|
451 | return COMM_TIME_OUT; \ |
---|
452 | } \ |
---|
453 | } |
---|
454 | |
---|
455 | /* Waits a reply from a modbus slave or a query from a modbus master. |
---|
456 | This function blocks for timeout seconds if there is no reply. |
---|
457 | |
---|
458 | In |
---|
459 | - msg_length_computed must be set to MSG_LENGTH_UNDEFINED if undefined |
---|
460 | |
---|
461 | Out |
---|
462 | - msg is an array of uint8_t to receive the message |
---|
463 | - p_msg_length, the variable is assigned to the number of |
---|
464 | characters received. This value won't be greater than |
---|
465 | msg_length_computed. |
---|
466 | |
---|
467 | Returns 0 in success or a negative value if an error occured. |
---|
468 | */ |
---|
469 | static int receive_msg(modbus_param_t *mb_param, |
---|
470 | int msg_length_computed, |
---|
471 | uint8_t *msg, int *p_msg_length) |
---|
472 | { |
---|
473 | int select_ret; |
---|
474 | int read_ret; |
---|
475 | fd_set rfds; |
---|
476 | struct timeval tv; |
---|
477 | int length_to_read; |
---|
478 | uint8_t *p_msg; |
---|
479 | enum { FUNCTION, BYTE, COMPLETE }; |
---|
480 | int state; |
---|
481 | |
---|
482 | if (mb_param->debug) { |
---|
483 | if (msg_length_computed == MSG_LENGTH_UNDEFINED) |
---|
484 | printf("Waiting for a message...\n"); |
---|
485 | else |
---|
486 | printf("Waiting for a message (%d bytes)...\n", |
---|
487 | msg_length_computed); |
---|
488 | } |
---|
489 | |
---|
490 | /* Add a file descriptor to the set */ |
---|
491 | FD_ZERO(&rfds); |
---|
492 | FD_SET(mb_param->fd, &rfds); |
---|
493 | |
---|
494 | if (msg_length_computed == MSG_LENGTH_UNDEFINED) { |
---|
495 | /* Wait for a message */ |
---|
496 | tv.tv_sec = 60; |
---|
497 | tv.tv_usec = 0; |
---|
498 | |
---|
499 | /* The message length is undefined (query receiving) so |
---|
500 | * we need to analyse the message step by step. |
---|
501 | * At the first step, we want to reach the function |
---|
502 | * code because all packets have that information. */ |
---|
503 | msg_length_computed = mb_param->header_length + 2; |
---|
504 | state = FUNCTION; |
---|
505 | } else { |
---|
506 | tv.tv_sec = 0; |
---|
507 | tv.tv_usec = TIME_OUT_BEGIN_OF_TRAME; |
---|
508 | state = COMPLETE; |
---|
509 | } |
---|
510 | |
---|
511 | length_to_read = msg_length_computed; |
---|
512 | |
---|
513 | select_ret = 0; |
---|
514 | WAIT_DATA(); |
---|
515 | |
---|
516 | /* Initialize the readin the message */ |
---|
517 | (*p_msg_length) = 0; |
---|
518 | p_msg = msg; |
---|
519 | |
---|
520 | while (select_ret) { |
---|
521 | if (mb_param->type_com == RTU) |
---|
522 | read_ret = read(mb_param->fd, p_msg, length_to_read); |
---|
523 | else |
---|
524 | read_ret = recv(mb_param->fd, p_msg, length_to_read, 0); |
---|
525 | |
---|
526 | if (read_ret == 0) { |
---|
527 | printf("Connection closed\n"); |
---|
528 | return CONNECTION_CLOSED; |
---|
529 | } else if (read_ret < 0) { |
---|
530 | /* The only negative possible value is -1 */ |
---|
531 | error_treat(mb_param, PORT_SOCKET_FAILURE, |
---|
532 | "Read port/socket failure"); |
---|
533 | return PORT_SOCKET_FAILURE; |
---|
534 | } |
---|
535 | |
---|
536 | /* Sums bytes received */ |
---|
537 | (*p_msg_length) += read_ret; |
---|
538 | |
---|
539 | /* Display the hex code of each character received */ |
---|
540 | if (mb_param->debug) { |
---|
541 | int i; |
---|
542 | for (i=0; i < read_ret; i++) |
---|
543 | printf("<%.2X>", p_msg[i]); |
---|
544 | } |
---|
545 | |
---|
546 | if ((*p_msg_length) < msg_length_computed) { |
---|
547 | /* Message incomplete */ |
---|
548 | length_to_read = msg_length_computed - (*p_msg_length); |
---|
549 | } else { |
---|
550 | switch (state) { |
---|
551 | case FUNCTION: |
---|
552 | /* Function code position */ |
---|
553 | length_to_read = compute_query_length_header(msg[mb_param->header_length + 1]); |
---|
554 | msg_length_computed += length_to_read; |
---|
555 | /* It's useless to check |
---|
556 | p_msg_length_computed value in this |
---|
557 | case (only defined values are used). */ |
---|
558 | state = BYTE; |
---|
559 | break; |
---|
560 | case BYTE: |
---|
561 | length_to_read = compute_query_length_data(mb_param, msg); |
---|
562 | msg_length_computed += length_to_read; |
---|
563 | if (msg_length_computed > MAX_MESSAGE_LENGTH) { |
---|
564 | error_treat(mb_param, TOO_MANY_DATA, "Too many data"); |
---|
565 | return TOO_MANY_DATA; |
---|
566 | } |
---|
567 | state = COMPLETE; |
---|
568 | break; |
---|
569 | case COMPLETE: |
---|
570 | length_to_read = 0; |
---|
571 | break; |
---|
572 | } |
---|
573 | } |
---|
574 | |
---|
575 | /* Moves the pointer to receive other data */ |
---|
576 | p_msg = &(p_msg[read_ret]); |
---|
577 | |
---|
578 | if (length_to_read > 0) { |
---|
579 | /* If no character at the buffer wait |
---|
580 | TIME_OUT_END_OF_TRAME before to generate an error. */ |
---|
581 | tv.tv_sec = 0; |
---|
582 | tv.tv_usec = TIME_OUT_END_OF_TRAME; |
---|
583 | |
---|
584 | WAIT_DATA(); |
---|
585 | } else { |
---|
586 | /* All chars are received */ |
---|
587 | select_ret = FALSE; |
---|
588 | } |
---|
589 | } |
---|
590 | |
---|
591 | if (mb_param->debug) |
---|
592 | printf("\n"); |
---|
593 | |
---|
594 | if (mb_param->type_com == RTU) { |
---|
595 | check_crc16(mb_param, msg, (*p_msg_length)); |
---|
596 | } |
---|
597 | |
---|
598 | /* OK */ |
---|
599 | return 0; |
---|
600 | } |
---|
601 | |
---|
602 | |
---|
603 | /* Receives the response and checks values (and checksum in RTU). |
---|
604 | |
---|
605 | Returns: |
---|
606 | - the number of values (bits or word) if success or the response |
---|
607 | length if no value is returned |
---|
608 | - less than 0 for exception errors |
---|
609 | |
---|
610 | Note: all functions used to send or receive data with modbus return |
---|
611 | these values. */ |
---|
612 | static int modbus_receive(modbus_param_t *mb_param, |
---|
613 | uint8_t *query, |
---|
614 | uint8_t *response) |
---|
615 | { |
---|
616 | int ret, i; |
---|
617 | int response_length; |
---|
618 | int response_length_computed; |
---|
619 | int offset = mb_param->header_length; |
---|
620 | |
---|
621 | response_length_computed = compute_response_length(mb_param, query); |
---|
622 | ret = receive_msg(mb_param, response_length_computed, |
---|
623 | response, &response_length); |
---|
624 | if (ret == 0) { |
---|
625 | /* GOOD RESPONSE */ |
---|
626 | int query_nb_value; |
---|
627 | int response_nb_value; |
---|
628 | |
---|
629 | /* The number of values is returned if it's corresponding |
---|
630 | * to the query */ |
---|
631 | switch (response[offset + 1]) { |
---|
632 | case FC_READ_COIL_STATUS: |
---|
633 | case FC_READ_INPUT_STATUS: |
---|
634 | /* Read functions, 8 values in a byte (nb |
---|
635 | * of values in the query and byte count in |
---|
636 | * the response. */ |
---|
637 | query_nb_value = (query[offset+4] << 8) + query[offset+5]; |
---|
638 | query_nb_value = (query_nb_value / 8) + ((query_nb_value % 8) ? 1 : 0); |
---|
639 | response_nb_value = response[offset + 2]; |
---|
640 | break; |
---|
641 | case FC_READ_HOLDING_REGISTERS: |
---|
642 | case FC_READ_INPUT_REGISTERS: |
---|
643 | /* Read functions 1 value = 2 bytes */ |
---|
644 | query_nb_value = (query[offset+4] << 8) + query[offset+5]; |
---|
645 | response_nb_value = (response[offset + 2] / 2); |
---|
646 | break; |
---|
647 | case FC_FORCE_MULTIPLE_COILS: |
---|
648 | case FC_PRESET_MULTIPLE_REGISTERS: |
---|
649 | /* N Write functions */ |
---|
650 | query_nb_value = (query[offset+4] << 8) + query[offset+5]; |
---|
651 | response_nb_value = (response[offset + 4] << 8) | response[offset + 5]; |
---|
652 | break; |
---|
653 | case FC_REPORT_SLAVE_ID: |
---|
654 | /* Report slave ID (bytes received) */ |
---|
655 | query_nb_value = response_nb_value = response_length; |
---|
656 | break; |
---|
657 | default: |
---|
658 | /* 1 Write functions & others */ |
---|
659 | query_nb_value = response_nb_value = 1; |
---|
660 | } |
---|
661 | |
---|
662 | if (query_nb_value == response_nb_value) |
---|
663 | { |
---|
664 | ret = response_nb_value; |
---|
665 | if (mb_param->saveRawData) |
---|
666 | { |
---|
667 | for (i = 0; i < response_length_computed; i++) |
---|
668 | mb_param->rawResponse[i]=response[i]; |
---|
669 | mb_param->rawResponseLength=response_length_computed; |
---|
670 | } |
---|
671 | |
---|
672 | } else { |
---|
673 | char *s_error = malloc(64 * sizeof(char)); |
---|
674 | sprintf(s_error, "Quantity (%d) not corresponding to the query (%d)", |
---|
675 | response_nb_value, query_nb_value); |
---|
676 | ret = ILLEGAL_DATA_VALUE; |
---|
677 | error_treat(mb_param, ILLEGAL_DATA_VALUE, s_error); |
---|
678 | free(s_error); |
---|
679 | } |
---|
680 | } else if (ret == COMM_TIME_OUT) { |
---|
681 | |
---|
682 | if (response_length == (offset + 3 + mb_param->checksum_length)) { |
---|
683 | /* EXCEPTION CODE RECEIVED */ |
---|
684 | |
---|
685 | /* Optimization allowed because exception response is |
---|
686 | the smallest trame in modbus protocol (3) so always |
---|
687 | raise a timeout error */ |
---|
688 | |
---|
689 | /* CRC must be checked here (not done in receive_msg) */ |
---|
690 | if (mb_param->type_com == RTU) { |
---|
691 | ret = check_crc16(mb_param, response, response_length); |
---|
692 | if (ret != 0) |
---|
693 | return ret; |
---|
694 | } |
---|
695 | |
---|
696 | /* Check for exception response. |
---|
697 | 0x80 + function is stored in the exception |
---|
698 | response. */ |
---|
699 | if (0x80 + query[offset + 1] == response[offset + 1]) { |
---|
700 | |
---|
701 | int exception_code = response[offset + 2]; |
---|
702 | // FIXME check test |
---|
703 | if (exception_code < NB_TAB_ERROR_MSG) { |
---|
704 | error_treat(mb_param, -exception_code, |
---|
705 | TAB_ERROR_MSG[response[offset + 2]]); |
---|
706 | /* RETURN THE EXCEPTION CODE */ |
---|
707 | /* Modbus error code is negative */ |
---|
708 | return -exception_code; |
---|
709 | } else { |
---|
710 | /* The chances are low to hit this |
---|
711 | case but it can avoid a vicious |
---|
712 | segfault */ |
---|
713 | char *s_error = malloc(64 * sizeof(char)); |
---|
714 | sprintf(s_error, |
---|
715 | "Invalid exception code %d", |
---|
716 | response[offset + 2]); |
---|
717 | error_treat(mb_param, INVALID_EXCEPTION_CODE, |
---|
718 | s_error); |
---|
719 | free(s_error); |
---|
720 | return INVALID_EXCEPTION_CODE; |
---|
721 | } |
---|
722 | } |
---|
723 | /* If doesn't return previously, return as |
---|
724 | TIME OUT here */ |
---|
725 | } |
---|
726 | |
---|
727 | /* COMMUNICATION TIME OUT */ |
---|
728 | error_treat(mb_param, ret, "Communication time out"); |
---|
729 | return ret; |
---|
730 | } |
---|
731 | |
---|
732 | return ret; |
---|
733 | } |
---|
734 | |
---|
735 | static int response_io_status(int address, int nb, |
---|
736 | uint8_t *tab_io_status, |
---|
737 | uint8_t *response, int offset) |
---|
738 | { |
---|
739 | int shift = 0; |
---|
740 | int byte = 0; |
---|
741 | int i; |
---|
742 | |
---|
743 | for (i = address; i < address+nb; i++) { |
---|
744 | byte |= tab_io_status[i] << shift; |
---|
745 | if (shift == 7) { |
---|
746 | /* Byte is full */ |
---|
747 | response[offset++] = byte; |
---|
748 | byte = shift = 0; |
---|
749 | } else { |
---|
750 | shift++; |
---|
751 | } |
---|
752 | } |
---|
753 | |
---|
754 | if (shift != 0) |
---|
755 | response[offset++] = byte; |
---|
756 | |
---|
757 | return offset; |
---|
758 | } |
---|
759 | |
---|
760 | /* Build the exception response */ |
---|
761 | static int response_exception(modbus_param_t *mb_param, sft_t *sft, |
---|
762 | int exception_code, uint8_t *response) |
---|
763 | { |
---|
764 | int response_length; |
---|
765 | |
---|
766 | sft->function = sft->function + 0x80; |
---|
767 | response_length = build_response_basis(mb_param, sft, response); |
---|
768 | |
---|
769 | /* Positive exception code */ |
---|
770 | response[response_length++] = -exception_code; |
---|
771 | |
---|
772 | return response_length; |
---|
773 | } |
---|
774 | |
---|
775 | /* Manages the received query. |
---|
776 | Analyses the query and constructs a response. |
---|
777 | If an error occurs, this function construct the response |
---|
778 | accordingly. |
---|
779 | */ |
---|
780 | void modbus_manage_query(modbus_param_t *mb_param, const uint8_t *query, |
---|
781 | int query_length, modbus_mapping_t *mb_mapping) |
---|
782 | { |
---|
783 | int offset = mb_param->header_length; |
---|
784 | int slave = query[offset]; |
---|
785 | int function = query[offset+1]; |
---|
786 | uint16_t address = (query[offset+2] << 8) + query[offset+3]; |
---|
787 | uint8_t response[MAX_MESSAGE_LENGTH]; |
---|
788 | int resp_length = 0; |
---|
789 | sft_t sft; |
---|
790 | |
---|
791 | sft.slave = slave; |
---|
792 | sft.function = function; |
---|
793 | if (mb_param->type_com == TCP) |
---|
794 | sft.t_id = (query[0] << 8) + query[1]; |
---|
795 | else |
---|
796 | sft.t_id = 0; |
---|
797 | |
---|
798 | switch (function) { |
---|
799 | case FC_READ_COIL_STATUS: { |
---|
800 | int nb = (query[offset+4] << 8) + query[offset+5]; |
---|
801 | |
---|
802 | if ((address + nb) > mb_mapping->nb_coil_status) { |
---|
803 | printf("Illegal data address %0X in read_coil_status\n", |
---|
804 | address + nb); |
---|
805 | resp_length = response_exception(mb_param, &sft, |
---|
806 | ILLEGAL_DATA_ADDRESS, response); |
---|
807 | } else { |
---|
808 | resp_length = build_response_basis(mb_param, &sft, response); |
---|
809 | response[resp_length++] = (nb / 8) + ((nb % 8) ? 1 : 0); |
---|
810 | resp_length = response_io_status(address, nb, |
---|
811 | mb_mapping->tab_coil_status, |
---|
812 | response, resp_length); |
---|
813 | } |
---|
814 | } |
---|
815 | break; |
---|
816 | case FC_READ_INPUT_STATUS: { |
---|
817 | /* Similar to coil status (but too much arguments to use a |
---|
818 | * function) */ |
---|
819 | int nb = (query[offset+4] << 8) + query[offset+5]; |
---|
820 | |
---|
821 | if ((address + nb) > mb_mapping->nb_input_status) { |
---|
822 | printf("Illegal data address %0X in read_input_status\n", |
---|
823 | address + nb); |
---|
824 | resp_length = response_exception(mb_param, &sft, |
---|
825 | ILLEGAL_DATA_ADDRESS, response); |
---|
826 | } else { |
---|
827 | resp_length = build_response_basis(mb_param, &sft, response); |
---|
828 | response[resp_length++] = (nb / 8) + ((nb % 8) ? 1 : 0); |
---|
829 | resp_length = response_io_status(address, nb, |
---|
830 | mb_mapping->tab_input_status, |
---|
831 | response, resp_length); |
---|
832 | } |
---|
833 | } |
---|
834 | break; |
---|
835 | case FC_READ_HOLDING_REGISTERS: { |
---|
836 | int nb = (query[offset+4] << 8) + query[offset+5]; |
---|
837 | |
---|
838 | if ((address + nb) > mb_mapping->nb_holding_registers) { |
---|
839 | printf("Illegal data address %0X in read_holding_registers\n", |
---|
840 | address + nb); |
---|
841 | resp_length = response_exception(mb_param, &sft, |
---|
842 | ILLEGAL_DATA_ADDRESS, response); |
---|
843 | } else { |
---|
844 | int i; |
---|
845 | |
---|
846 | resp_length = build_response_basis(mb_param, &sft, response); |
---|
847 | response[resp_length++] = nb << 1; |
---|
848 | for (i = address; i < address + nb; i++) { |
---|
849 | response[resp_length++] = mb_mapping->tab_holding_registers[i] >> 8; |
---|
850 | response[resp_length++] = mb_mapping->tab_holding_registers[i] & 0xFF; |
---|
851 | } |
---|
852 | } |
---|
853 | } |
---|
854 | break; |
---|
855 | case FC_READ_INPUT_REGISTERS: { |
---|
856 | /* Similar to holding registers (but too much arguments to use a |
---|
857 | * function) */ |
---|
858 | int nb = (query[offset+4] << 8) + query[offset+5]; |
---|
859 | |
---|
860 | if ((address + nb) > mb_mapping->nb_input_registers) { |
---|
861 | printf("Illegal data address %0X in read_input_registers\n", |
---|
862 | address + nb); |
---|
863 | resp_length = response_exception(mb_param, &sft, |
---|
864 | ILLEGAL_DATA_ADDRESS, response); |
---|
865 | } else { |
---|
866 | int i; |
---|
867 | |
---|
868 | resp_length = build_response_basis(mb_param, &sft, response); |
---|
869 | response[resp_length++] = nb << 1; |
---|
870 | for (i = address; i < address + nb; i++) { |
---|
871 | response[resp_length++] = mb_mapping->tab_input_registers[i] >> 8; |
---|
872 | response[resp_length++] = mb_mapping->tab_input_registers[i] & 0xFF; |
---|
873 | } |
---|
874 | } |
---|
875 | } |
---|
876 | break; |
---|
877 | case FC_FORCE_SINGLE_COIL: |
---|
878 | if (address >= mb_mapping->nb_coil_status) { |
---|
879 | printf("Illegal data address %0X in force_singe_coil\n", address); |
---|
880 | resp_length = response_exception(mb_param, &sft, |
---|
881 | ILLEGAL_DATA_ADDRESS, response); |
---|
882 | } else { |
---|
883 | int data = (query[offset+4] << 8) + query[offset+5]; |
---|
884 | |
---|
885 | if (data == 0xFF00 || data == 0x0) { |
---|
886 | mb_mapping->tab_coil_status[address] = (data) ? ON : OFF; |
---|
887 | |
---|
888 | /* In RTU mode, the CRC is computed |
---|
889 | and added to the query by modbus_send */ |
---|
890 | memcpy(response, query, query_length - mb_param->checksum_length); |
---|
891 | resp_length = query_length; |
---|
892 | } else { |
---|
893 | printf("Illegal data value %0X in force_single_coil request at address %0X\n", |
---|
894 | data, address); |
---|
895 | resp_length = response_exception(mb_param, &sft, |
---|
896 | ILLEGAL_DATA_VALUE, response); |
---|
897 | } |
---|
898 | } |
---|
899 | break; |
---|
900 | case FC_PRESET_SINGLE_REGISTER: |
---|
901 | if (address >= mb_mapping->nb_holding_registers) { |
---|
902 | printf("Illegal data address %0X in preset_holding_register\n", address); |
---|
903 | resp_length = response_exception(mb_param, &sft, |
---|
904 | ILLEGAL_DATA_ADDRESS, response); |
---|
905 | } else { |
---|
906 | int data = (query[offset+4] << 8) + query[offset+5]; |
---|
907 | |
---|
908 | mb_mapping->tab_holding_registers[address] = data; |
---|
909 | memcpy(response, query, query_length - mb_param->checksum_length); |
---|
910 | resp_length = query_length; |
---|
911 | } |
---|
912 | break; |
---|
913 | case FC_FORCE_MULTIPLE_COILS: { |
---|
914 | int nb = (query[offset+4] << 8) + query[offset+5]; |
---|
915 | |
---|
916 | if ((address + nb) > mb_mapping->nb_coil_status) { |
---|
917 | printf("Illegal data address %0X in force_multiple_coils\n", |
---|
918 | address + nb); |
---|
919 | resp_length = response_exception(mb_param, &sft, |
---|
920 | ILLEGAL_DATA_ADDRESS, response); |
---|
921 | } else { |
---|
922 | /* 6 = byte count, 7 = first byte of data */ |
---|
923 | set_bits_from_bytes(mb_mapping->tab_coil_status, address, nb, &query[offset + 7]); |
---|
924 | |
---|
925 | resp_length = build_response_basis(mb_param, &sft, response); |
---|
926 | /* 4 to copy the coil address (2) and the quantity of coils */ |
---|
927 | memcpy(response + resp_length, query + resp_length, 4); |
---|
928 | resp_length += 4; |
---|
929 | } |
---|
930 | } |
---|
931 | break; |
---|
932 | case FC_PRESET_MULTIPLE_REGISTERS: { |
---|
933 | int nb = (query[offset+4] << 8) + query[offset+5]; |
---|
934 | |
---|
935 | if ((address + nb) > mb_mapping->nb_holding_registers) { |
---|
936 | printf("Illegal data address %0X in preset_multiple_registers\n", |
---|
937 | address + nb); |
---|
938 | resp_length = response_exception(mb_param, &sft, |
---|
939 | ILLEGAL_DATA_ADDRESS, response); |
---|
940 | } else { |
---|
941 | int i, j; |
---|
942 | for (i = address, j = 0; i < address + nb; i++, j += 2) { |
---|
943 | /* 6 = byte count, 7 and 8 = first value */ |
---|
944 | mb_mapping->tab_holding_registers[i] = |
---|
945 | (query[offset + 7 + j] << 8) + query[offset + 8 + j]; |
---|
946 | } |
---|
947 | |
---|
948 | resp_length = build_response_basis(mb_param, &sft, response); |
---|
949 | /* 4 to copy the address (2) and the no. of registers */ |
---|
950 | memcpy(response + resp_length, query + resp_length, 4); |
---|
951 | resp_length += 4; |
---|
952 | } |
---|
953 | } |
---|
954 | break; |
---|
955 | case FC_READ_EXCEPTION_STATUS: |
---|
956 | case FC_REPORT_SLAVE_ID: |
---|
957 | printf("Not implemented\n"); |
---|
958 | break; |
---|
959 | } |
---|
960 | |
---|
961 | modbus_send(mb_param, response, resp_length); |
---|
962 | } |
---|
963 | |
---|
964 | /* Listens any message on a socket or file descriptor. |
---|
965 | Returns: |
---|
966 | - 0 if OK, or a negative error number if the request fails |
---|
967 | - query, message received |
---|
968 | - query_length, length in bytes of the message */ |
---|
969 | int modbus_listen(modbus_param_t *mb_param, uint8_t *query, int *query_length) |
---|
970 | { |
---|
971 | int ret; |
---|
972 | |
---|
973 | /* The length of the query to receive isn't known. */ |
---|
974 | ret = receive_msg(mb_param, MSG_LENGTH_UNDEFINED, query, query_length); |
---|
975 | |
---|
976 | return ret; |
---|
977 | } |
---|
978 | |
---|
979 | /* Reads IO status */ |
---|
980 | static int read_io_status(modbus_param_t *mb_param, int slave, int function, |
---|
981 | int start_addr, int nb, uint8_t *data_dest) |
---|
982 | { |
---|
983 | int ret; |
---|
984 | int query_length; |
---|
985 | |
---|
986 | uint8_t query[MIN_QUERY_LENGTH]; |
---|
987 | uint8_t response[MAX_MESSAGE_LENGTH]; |
---|
988 | |
---|
989 | query_length = build_query_basis(mb_param, slave, function, |
---|
990 | start_addr, nb, query); |
---|
991 | |
---|
992 | ret = modbus_send(mb_param, query, query_length); |
---|
993 | if (ret > 0) { |
---|
994 | int i, temp, bit; |
---|
995 | int pos = 0; |
---|
996 | int processed = 0; |
---|
997 | int offset; |
---|
998 | int offset_length; |
---|
999 | |
---|
1000 | ret = modbus_receive(mb_param, query, response); |
---|
1001 | if (ret < 0) |
---|
1002 | return ret; |
---|
1003 | |
---|
1004 | offset = mb_param->header_length; |
---|
1005 | |
---|
1006 | offset_length = offset + ret; |
---|
1007 | mb_param->response_length=offset_length+2; |
---|
1008 | for (i = offset; i < offset_length; i++) { |
---|
1009 | /* Shift reg hi_byte to temp */ |
---|
1010 | temp = response[3 + i]; |
---|
1011 | |
---|
1012 | for (bit = 0x01; (bit & 0xff) && (processed < nb);) { |
---|
1013 | data_dest[pos++] = (temp & bit) ? TRUE : FALSE; |
---|
1014 | processed++; |
---|
1015 | bit = bit << 1; |
---|
1016 | } |
---|
1017 | |
---|
1018 | } |
---|
1019 | } |
---|
1020 | |
---|
1021 | return ret; |
---|
1022 | } |
---|
1023 | |
---|
1024 | /* Reads the boolean status of coils and sets the array elements |
---|
1025 | in the destination to TRUE or FALSE. */ |
---|
1026 | int read_coil_status(modbus_param_t *mb_param, int slave, int start_addr, |
---|
1027 | int nb, uint8_t *data_dest) |
---|
1028 | { |
---|
1029 | int status; |
---|
1030 | |
---|
1031 | if (nb > MAX_STATUS) { |
---|
1032 | printf("ERROR Too many coils status requested (%d > %d)\n", |
---|
1033 | nb, MAX_STATUS); |
---|
1034 | return TOO_MANY_DATA; |
---|
1035 | } |
---|
1036 | |
---|
1037 | status = read_io_status(mb_param, slave, FC_READ_COIL_STATUS, |
---|
1038 | start_addr, nb, data_dest); |
---|
1039 | |
---|
1040 | if (status > 0) |
---|
1041 | status = nb; |
---|
1042 | |
---|
1043 | return status; |
---|
1044 | } |
---|
1045 | |
---|
1046 | |
---|
1047 | /* Same as read_coil_status but reads the slaves input table */ |
---|
1048 | int read_input_status(modbus_param_t *mb_param, int slave, int start_addr, |
---|
1049 | int nb, uint8_t *data_dest) |
---|
1050 | { |
---|
1051 | int status; |
---|
1052 | |
---|
1053 | if (nb > MAX_STATUS) { |
---|
1054 | printf("ERROR Too many input status requested (%d > %d)\n", |
---|
1055 | nb, MAX_STATUS); |
---|
1056 | return TOO_MANY_DATA; |
---|
1057 | } |
---|
1058 | |
---|
1059 | status = read_io_status(mb_param, slave, FC_READ_INPUT_STATUS, |
---|
1060 | start_addr, nb, data_dest); |
---|
1061 | |
---|
1062 | if (status > 0) |
---|
1063 | status = nb; |
---|
1064 | |
---|
1065 | return status; |
---|
1066 | } |
---|
1067 | |
---|
1068 | /* Reads the data from a modbus slave and put that data into an array */ |
---|
1069 | static int read_registers(modbus_param_t *mb_param, int slave, int function, |
---|
1070 | int start_addr, int nb, uint16_t *data_dest) |
---|
1071 | { |
---|
1072 | int ret; |
---|
1073 | int query_length; |
---|
1074 | uint8_t query[MIN_QUERY_LENGTH]; |
---|
1075 | uint8_t response[MAX_MESSAGE_LENGTH]; |
---|
1076 | |
---|
1077 | if (nb > MAX_REGISTERS) { |
---|
1078 | printf("EROOR Too many holding registers requested (%d > %d)\n", |
---|
1079 | nb, MAX_REGISTERS); |
---|
1080 | return TOO_MANY_DATA; |
---|
1081 | } |
---|
1082 | |
---|
1083 | query_length = build_query_basis(mb_param, slave, function, |
---|
1084 | start_addr, nb, query); |
---|
1085 | |
---|
1086 | ret = modbus_send(mb_param, query, query_length); |
---|
1087 | if (ret > 0) { |
---|
1088 | int offset; |
---|
1089 | int i; |
---|
1090 | |
---|
1091 | ret = modbus_receive(mb_param, query, response); |
---|
1092 | |
---|
1093 | offset = mb_param->header_length; |
---|
1094 | mb_param->response_length=offset+ret+3; |
---|
1095 | |
---|
1096 | /* If ret is negative, the loop is jumped ! */ |
---|
1097 | for (i = 0; i < ret; i++) { |
---|
1098 | /* shift reg hi_byte to temp OR with lo_byte */ |
---|
1099 | data_dest[i] = (response[offset + 3 + (i << 1)] << 8) | |
---|
1100 | response[offset + 4 + (i << 1)]; |
---|
1101 | } |
---|
1102 | } |
---|
1103 | |
---|
1104 | return ret; |
---|
1105 | } |
---|
1106 | |
---|
1107 | /* Reads the holding registers in a slave and put the data into an |
---|
1108 | array */ |
---|
1109 | int read_holding_registers(modbus_param_t *mb_param, int slave, |
---|
1110 | int start_addr, int nb, uint16_t *data_dest) |
---|
1111 | { |
---|
1112 | int status; |
---|
1113 | |
---|
1114 | if (nb > MAX_REGISTERS) { |
---|
1115 | printf("ERROR Too many holding registers requested (%d > %d)\n", |
---|
1116 | nb, MAX_REGISTERS); |
---|
1117 | return TOO_MANY_DATA; |
---|
1118 | } |
---|
1119 | |
---|
1120 | status = read_registers(mb_param, slave, FC_READ_HOLDING_REGISTERS, |
---|
1121 | start_addr, nb, data_dest); |
---|
1122 | return status; |
---|
1123 | } |
---|
1124 | |
---|
1125 | /* Reads the input registers in a slave and put the data into |
---|
1126 | an array */ |
---|
1127 | int read_input_registers(modbus_param_t *mb_param, int slave, |
---|
1128 | int start_addr, int nb, uint16_t *data_dest) |
---|
1129 | { |
---|
1130 | int status; |
---|
1131 | |
---|
1132 | if (nb > MAX_REGISTERS) { |
---|
1133 | printf("ERROR Too many input registers requested (%d > %d)\n", |
---|
1134 | nb, MAX_REGISTERS); |
---|
1135 | return TOO_MANY_DATA; |
---|
1136 | } |
---|
1137 | |
---|
1138 | status = read_registers(mb_param, slave, FC_READ_INPUT_REGISTERS, |
---|
1139 | start_addr, nb, data_dest); |
---|
1140 | |
---|
1141 | return status; |
---|
1142 | } |
---|
1143 | |
---|
1144 | /* Sends a value to a register in a slave. |
---|
1145 | Used by force_single_coil and preset_single_register */ |
---|
1146 | static int set_single(modbus_param_t *mb_param, int slave, int function, |
---|
1147 | int addr, int value) |
---|
1148 | { |
---|
1149 | int ret; |
---|
1150 | int query_length; |
---|
1151 | uint8_t query[MIN_QUERY_LENGTH]; |
---|
1152 | |
---|
1153 | query_length = build_query_basis(mb_param, slave, function, |
---|
1154 | addr, value, query); |
---|
1155 | |
---|
1156 | ret = modbus_send(mb_param, query, query_length); |
---|
1157 | if (ret > 0) { |
---|
1158 | /* Used by force_single_coil and |
---|
1159 | * preset_single_register */ |
---|
1160 | uint8_t response[MIN_QUERY_LENGTH]; |
---|
1161 | ret = modbus_receive(mb_param, query, response); |
---|
1162 | } |
---|
1163 | |
---|
1164 | return ret; |
---|
1165 | } |
---|
1166 | |
---|
1167 | /* Turns ON or OFF a single coil in the slave device */ |
---|
1168 | int force_single_coil(modbus_param_t *mb_param, int slave, |
---|
1169 | int coil_addr, int state) |
---|
1170 | { |
---|
1171 | int status; |
---|
1172 | |
---|
1173 | if (state) |
---|
1174 | state = 0xFF00; |
---|
1175 | |
---|
1176 | status = set_single(mb_param, slave, FC_FORCE_SINGLE_COIL, |
---|
1177 | coil_addr, state); |
---|
1178 | |
---|
1179 | return status; |
---|
1180 | } |
---|
1181 | |
---|
1182 | /* Sets a value in one holding register in the slave device */ |
---|
1183 | int preset_single_register(modbus_param_t *mb_param, int slave, |
---|
1184 | int reg_addr, int value) |
---|
1185 | { |
---|
1186 | int status; |
---|
1187 | |
---|
1188 | status = set_single(mb_param, slave, FC_PRESET_SINGLE_REGISTER, |
---|
1189 | reg_addr, value); |
---|
1190 | |
---|
1191 | return status; |
---|
1192 | } |
---|
1193 | |
---|
1194 | /* Sets/resets the coils in the slave from an array in argument */ |
---|
1195 | int force_multiple_coils(modbus_param_t *mb_param, int slave, |
---|
1196 | int start_addr, int nb, |
---|
1197 | const uint8_t *data_src) |
---|
1198 | { |
---|
1199 | int ret; |
---|
1200 | int i; |
---|
1201 | int byte_count; |
---|
1202 | int query_length; |
---|
1203 | int coil_check = 0; |
---|
1204 | int pos = 0; |
---|
1205 | |
---|
1206 | uint8_t query[MAX_MESSAGE_LENGTH]; |
---|
1207 | |
---|
1208 | if (nb > MAX_STATUS) { |
---|
1209 | printf("ERROR Writing to too many coils (%d > %d)\n", |
---|
1210 | nb, MAX_STATUS); |
---|
1211 | return TOO_MANY_DATA; |
---|
1212 | } |
---|
1213 | |
---|
1214 | query_length = build_query_basis(mb_param, slave, |
---|
1215 | FC_FORCE_MULTIPLE_COILS, |
---|
1216 | start_addr, nb, query); |
---|
1217 | byte_count = (nb / 8) + ((nb % 8) ? 1 : 0); |
---|
1218 | query[query_length++] = byte_count; |
---|
1219 | |
---|
1220 | for (i = 0; i < byte_count; i++) { |
---|
1221 | int bit; |
---|
1222 | |
---|
1223 | bit = 0x01; |
---|
1224 | query[query_length] = 0; |
---|
1225 | |
---|
1226 | while ((bit & 0xFF) && (coil_check++ < nb)) { |
---|
1227 | if (data_src[pos++]) |
---|
1228 | query[query_length] |= bit; |
---|
1229 | else |
---|
1230 | query[query_length] &=~ bit; |
---|
1231 | |
---|
1232 | bit = bit << 1; |
---|
1233 | } |
---|
1234 | query_length++; |
---|
1235 | } |
---|
1236 | |
---|
1237 | ret = modbus_send(mb_param, query, query_length); |
---|
1238 | if (ret > 0) { |
---|
1239 | uint8_t response[MAX_MESSAGE_LENGTH]; |
---|
1240 | ret = modbus_receive(mb_param, query, response); |
---|
1241 | } |
---|
1242 | |
---|
1243 | |
---|
1244 | return ret; |
---|
1245 | } |
---|
1246 | |
---|
1247 | /* Copies the values in the slave from the array given in argument */ |
---|
1248 | int preset_multiple_registers(modbus_param_t *mb_param, int slave, |
---|
1249 | int start_addr, int nb, |
---|
1250 | const uint16_t *data_src) |
---|
1251 | { |
---|
1252 | int ret; |
---|
1253 | int i; |
---|
1254 | int query_length; |
---|
1255 | int byte_count; |
---|
1256 | |
---|
1257 | uint8_t query[MAX_MESSAGE_LENGTH]; |
---|
1258 | |
---|
1259 | if (nb > MAX_REGISTERS) { |
---|
1260 | printf("ERROR Trying to write to too many registers (%d > %d)\n", |
---|
1261 | nb, MAX_REGISTERS); |
---|
1262 | return TOO_MANY_DATA; |
---|
1263 | } |
---|
1264 | |
---|
1265 | query_length = build_query_basis(mb_param, slave, |
---|
1266 | FC_PRESET_MULTIPLE_REGISTERS, |
---|
1267 | start_addr, nb, query); |
---|
1268 | byte_count = nb * 2; |
---|
1269 | query[query_length++] = byte_count; |
---|
1270 | |
---|
1271 | for (i = 0; i < nb; i++) { |
---|
1272 | query[query_length++] = data_src[i] >> 8; |
---|
1273 | query[query_length++] = data_src[i] & 0x00FF; |
---|
1274 | } |
---|
1275 | |
---|
1276 | ret = modbus_send(mb_param, query, query_length); |
---|
1277 | if (ret > 0) { |
---|
1278 | uint8_t response[MAX_MESSAGE_LENGTH]; |
---|
1279 | ret = modbus_receive(mb_param, query, response); |
---|
1280 | } |
---|
1281 | |
---|
1282 | return ret; |
---|
1283 | } |
---|
1284 | |
---|
1285 | /* Returns the slave id! */ |
---|
1286 | int report_slave_id(modbus_param_t *mb_param, int slave, |
---|
1287 | uint8_t *data_dest) |
---|
1288 | { |
---|
1289 | int ret; |
---|
1290 | int query_length; |
---|
1291 | uint8_t query[MIN_QUERY_LENGTH]; |
---|
1292 | |
---|
1293 | query_length = build_query_basis(mb_param, slave, FC_REPORT_SLAVE_ID, |
---|
1294 | 0, 0, query); |
---|
1295 | |
---|
1296 | /* HACKISH, start_addr and count are not used */ |
---|
1297 | query_length -= 4; |
---|
1298 | |
---|
1299 | ret = modbus_send(mb_param, query, query_length); |
---|
1300 | if (ret > 0) { |
---|
1301 | int i; |
---|
1302 | int offset; |
---|
1303 | int offset_length; |
---|
1304 | uint8_t response[MAX_MESSAGE_LENGTH]; |
---|
1305 | |
---|
1306 | /* Byte count, slave id, run indicator status, |
---|
1307 | additional data */ |
---|
1308 | ret = modbus_receive(mb_param, query, response); |
---|
1309 | if (ret < 0) |
---|
1310 | return ret; |
---|
1311 | |
---|
1312 | offset = mb_param->header_length; |
---|
1313 | offset_length = offset + ret; |
---|
1314 | |
---|
1315 | for (i = offset; i < offset_length; i++) |
---|
1316 | data_dest[i] = response[i]; |
---|
1317 | } |
---|
1318 | |
---|
1319 | return ret; |
---|
1320 | } |
---|
1321 | |
---|
1322 | /* Initializes the modbus_param_t structure for RTU |
---|
1323 | - device: "/dev/ttyS0" |
---|
1324 | - baud: 9600, 19200, 57600, 115200, etc |
---|
1325 | - parity: "even", "odd" or "none" |
---|
1326 | - data_bits: 5, 6, 7, 8 |
---|
1327 | - stop_bits: 1, 2 |
---|
1328 | */ |
---|
1329 | void modbus_init_rtu(modbus_param_t *mb_param, const char *device, |
---|
1330 | int baud, const char *parity, int data_bit, |
---|
1331 | int stop_bit) |
---|
1332 | { |
---|
1333 | memset(mb_param, 0, sizeof(modbus_param_t)); |
---|
1334 | strcpy(mb_param->device, device); |
---|
1335 | mb_param->baud = baud; |
---|
1336 | strcpy(mb_param->parity, parity); |
---|
1337 | mb_param->debug = FALSE; |
---|
1338 | mb_param->data_bit = data_bit; |
---|
1339 | mb_param->stop_bit = stop_bit; |
---|
1340 | mb_param->type_com = RTU; |
---|
1341 | mb_param->header_length = HEADER_LENGTH_RTU; |
---|
1342 | mb_param->checksum_length = CHECKSUM_LENGTH_RTU; |
---|
1343 | mb_param->saveRawData=FALSE; |
---|
1344 | } |
---|
1345 | |
---|
1346 | /* Initializes the modbus_param_t structure for TCP. |
---|
1347 | - ip : "192.168.0.5" |
---|
1348 | - port : 1099 |
---|
1349 | |
---|
1350 | Set the port to MODBUS_TCP_DEFAULT_PORT to use the default one |
---|
1351 | (502). It's convenient to use a port number greater than or equal |
---|
1352 | to 1024 because it's not necessary to be root to use this port |
---|
1353 | number. |
---|
1354 | */ |
---|
1355 | void modbus_init_tcp(modbus_param_t *mb_param, const char *ip, int port) |
---|
1356 | { |
---|
1357 | memset(mb_param, 0, sizeof(modbus_param_t)); |
---|
1358 | strncpy(mb_param->ip, ip, sizeof(char)*16); |
---|
1359 | mb_param->port = port; |
---|
1360 | mb_param->type_com = TCP; |
---|
1361 | mb_param->header_length = HEADER_LENGTH_TCP; |
---|
1362 | mb_param->checksum_length = CHECKSUM_LENGTH_TCP; |
---|
1363 | mb_param->error_handling = FLUSH_OR_RECONNECT_ON_ERROR; |
---|
1364 | mb_param->saveRawData=FALSE; |
---|
1365 | } |
---|
1366 | |
---|
1367 | /* By default, the error handling mode used is FLUSH_OR_RECONNECT_ON_ERROR. |
---|
1368 | |
---|
1369 | With FLUSH_OR_RECONNECT_ON_ERROR, the library will flush to I/O |
---|
1370 | port in RTU mode or attempt an immediate reconnection which may |
---|
1371 | hang for several seconds if the network to the remote target unit |
---|
1372 | is down in TCP mode. |
---|
1373 | |
---|
1374 | With NOP_ON_ERROR, it is expected that the application will |
---|
1375 | check for error returns and deal with them as necessary. |
---|
1376 | */ |
---|
1377 | void modbus_set_error_handling(modbus_param_t *mb_param, |
---|
1378 | error_handling_t error_handling) |
---|
1379 | { |
---|
1380 | if (error_handling == FLUSH_OR_RECONNECT_ON_ERROR || |
---|
1381 | error_handling == NOP_ON_ERROR) { |
---|
1382 | mb_param->error_handling = error_handling; |
---|
1383 | } else { |
---|
1384 | printf("Invalid setting for error handling (not changed)\n"); |
---|
1385 | } |
---|
1386 | } |
---|
1387 | |
---|
1388 | |
---|
1389 | /* Sets up a serial port for RTU communications */ |
---|
1390 | static int modbus_connect_rtu(modbus_param_t *mb_param) |
---|
1391 | { |
---|
1392 | struct termios tios; |
---|
1393 | speed_t speed; |
---|
1394 | |
---|
1395 | if (mb_param->debug) { |
---|
1396 | printf("Opening %s at %d bauds (%s)\n", |
---|
1397 | mb_param->device, mb_param->baud, mb_param->parity); |
---|
1398 | } |
---|
1399 | |
---|
1400 | /* The O_NOCTTY flag tells UNIX that this program doesn't want |
---|
1401 | to be the "controlling terminal" for that port. If you |
---|
1402 | don't specify this then any input (such as keyboard abort |
---|
1403 | signals and so forth) will affect your process |
---|
1404 | |
---|
1405 | Timeouts are ignored in canonical input mode or when the |
---|
1406 | NDELAY option is set on the file via open or fcntl */ |
---|
1407 | mb_param->fd = open(mb_param->device, O_RDWR | O_NOCTTY | O_NDELAY); |
---|
1408 | if (mb_param->fd < 0) { |
---|
1409 | perror("open"); |
---|
1410 | printf("ERROR Can't open the device %s (errno %d)\n", |
---|
1411 | mb_param->device, errno); |
---|
1412 | return -1; |
---|
1413 | } |
---|
1414 | |
---|
1415 | /* Save */ |
---|
1416 | tcgetattr(mb_param->fd, &(mb_param->old_tios)); |
---|
1417 | |
---|
1418 | memset(&tios, 0, sizeof(struct termios)); |
---|
1419 | |
---|
1420 | /* C_ISPEED Input baud (new interface) |
---|
1421 | C_OSPEED Output baud (new interface) |
---|
1422 | */ |
---|
1423 | switch (mb_param->baud) { |
---|
1424 | case 110: |
---|
1425 | speed = B110; |
---|
1426 | break; |
---|
1427 | case 300: |
---|
1428 | speed = B300; |
---|
1429 | break; |
---|
1430 | case 600: |
---|
1431 | speed = B600; |
---|
1432 | break; |
---|
1433 | case 1200: |
---|
1434 | speed = B1200; |
---|
1435 | break; |
---|
1436 | case 2400: |
---|
1437 | speed = B2400; |
---|
1438 | break; |
---|
1439 | case 4800: |
---|
1440 | speed = B4800; |
---|
1441 | break; |
---|
1442 | case 9600: |
---|
1443 | speed = B9600; |
---|
1444 | break; |
---|
1445 | case 19200: |
---|
1446 | speed = B19200; |
---|
1447 | break; |
---|
1448 | case 38400: |
---|
1449 | speed = B38400; |
---|
1450 | break; |
---|
1451 | case 57600: |
---|
1452 | speed = B57600; |
---|
1453 | break; |
---|
1454 | case 115200: |
---|
1455 | speed = B115200; |
---|
1456 | break; |
---|
1457 | default: |
---|
1458 | speed = B9600; |
---|
1459 | printf("WARNING Unknown baud rate %d for %s (B9600 used)\n", |
---|
1460 | mb_param->baud, mb_param->device); |
---|
1461 | } |
---|
1462 | |
---|
1463 | /* Set the baud rate */ |
---|
1464 | if ((cfsetispeed(&tios, speed) < 0) || |
---|
1465 | (cfsetospeed(&tios, speed) < 0)) { |
---|
1466 | perror("cfsetispeed/cfsetospeed\n"); |
---|
1467 | return -1; |
---|
1468 | } |
---|
1469 | |
---|
1470 | /* C_CFLAG Control options |
---|
1471 | CLOCAL Local line - do not change "owner" of port |
---|
1472 | CREAD Enable receiver |
---|
1473 | */ |
---|
1474 | tios.c_cflag |= (CREAD | CLOCAL); |
---|
1475 | /* CSIZE, HUPCL, CRTSCTS (hardware flow control) */ |
---|
1476 | |
---|
1477 | /* Set data bits (5, 6, 7, 8 bits) |
---|
1478 | CSIZE Bit mask for data bits |
---|
1479 | */ |
---|
1480 | tios.c_cflag &= ~CSIZE; |
---|
1481 | switch (mb_param->data_bit) { |
---|
1482 | case 5: |
---|
1483 | tios.c_cflag |= CS5; |
---|
1484 | break; |
---|
1485 | case 6: |
---|
1486 | tios.c_cflag |= CS6; |
---|
1487 | break; |
---|
1488 | case 7: |
---|
1489 | tios.c_cflag |= CS7; |
---|
1490 | break; |
---|
1491 | case 8: |
---|
1492 | default: |
---|
1493 | tios.c_cflag |= CS8; |
---|
1494 | break; |
---|
1495 | } |
---|
1496 | |
---|
1497 | /* Stop bit (1 or 2) */ |
---|
1498 | if (mb_param->stop_bit == 1) |
---|
1499 | tios.c_cflag &=~ CSTOPB; |
---|
1500 | else /* 2 */ |
---|
1501 | tios.c_cflag |= CSTOPB; |
---|
1502 | |
---|
1503 | /* PARENB Enable parity bit |
---|
1504 | PARODD Use odd parity instead of even */ |
---|
1505 | if (strncmp(mb_param->parity, "none", 4) == 0) { |
---|
1506 | tios.c_cflag &=~ PARENB; |
---|
1507 | } else if (strncmp(mb_param->parity, "even", 4) == 0) { |
---|
1508 | tios.c_cflag |= PARENB; |
---|
1509 | tios.c_cflag &=~ PARODD; |
---|
1510 | } else { |
---|
1511 | /* odd */ |
---|
1512 | tios.c_cflag |= PARENB; |
---|
1513 | tios.c_cflag |= PARODD; |
---|
1514 | } |
---|
1515 | |
---|
1516 | /* Read the man page of termios if you need more information. */ |
---|
1517 | |
---|
1518 | /* This field isn't used on POSIX systems |
---|
1519 | tios.c_line = 0; |
---|
1520 | */ |
---|
1521 | |
---|
1522 | /* C_LFLAG Line options |
---|
1523 | |
---|
1524 | ISIG Enable SIGINTR, SIGSUSP, SIGDSUSP, and SIGQUIT signals |
---|
1525 | ICANON Enable canonical input (else raw) |
---|
1526 | XCASE Map uppercase \lowercase (obsolete) |
---|
1527 | ECHO Enable echoing of input characters |
---|
1528 | ECHOE Echo erase character as BS-SP-BS |
---|
1529 | ECHOK Echo NL after kill character |
---|
1530 | ECHONL Echo NL |
---|
1531 | NOFLSH Disable flushing of input buffers after |
---|
1532 | interrupt or quit characters |
---|
1533 | IEXTEN Enable extended functions |
---|
1534 | ECHOCTL Echo control characters as ^char and delete as ~? |
---|
1535 | ECHOPRT Echo erased character as character erased |
---|
1536 | ECHOKE BS-SP-BS entire line on line kill |
---|
1537 | FLUSHO Output being flushed |
---|
1538 | PENDIN Retype pending input at next read or input char |
---|
1539 | TOSTOP Send SIGTTOU for background output |
---|
1540 | |
---|
1541 | Canonical input is line-oriented. Input characters are put |
---|
1542 | into a buffer which can be edited interactively by the user |
---|
1543 | until a CR (carriage return) or LF (line feed) character is |
---|
1544 | received. |
---|
1545 | |
---|
1546 | Raw input is unprocessed. Input characters are passed |
---|
1547 | through exactly as they are received, when they are |
---|
1548 | received. Generally you'll deselect the ICANON, ECHO, |
---|
1549 | ECHOE, and ISIG options when using raw input |
---|
1550 | */ |
---|
1551 | |
---|
1552 | /* Raw input */ |
---|
1553 | tios.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG); |
---|
1554 | |
---|
1555 | /* C_IFLAG Input options |
---|
1556 | |
---|
1557 | Constant Description |
---|
1558 | INPCK Enable parity check |
---|
1559 | IGNPAR Ignore parity errors |
---|
1560 | PARMRK Mark parity errors |
---|
1561 | ISTRIP Strip parity bits |
---|
1562 | IXON Enable software flow control (outgoing) |
---|
1563 | IXOFF Enable software flow control (incoming) |
---|
1564 | IXANY Allow any character to start flow again |
---|
1565 | IGNBRK Ignore break condition |
---|
1566 | BRKINT Send a SIGINT when a break condition is detected |
---|
1567 | INLCR Map NL to CR |
---|
1568 | IGNCR Ignore CR |
---|
1569 | ICRNL Map CR to NL |
---|
1570 | IUCLC Map uppercase to lowercase |
---|
1571 | IMAXBEL Echo BEL on input line too long |
---|
1572 | */ |
---|
1573 | if (strncmp(mb_param->parity, "none", 4) == 0) { |
---|
1574 | tios.c_iflag &= ~INPCK; |
---|
1575 | } else { |
---|
1576 | tios.c_iflag |= INPCK; |
---|
1577 | } |
---|
1578 | |
---|
1579 | /* Software flow control is disabled */ |
---|
1580 | tios.c_iflag &= ~(IXON | IXOFF | IXANY); |
---|
1581 | |
---|
1582 | /* C_OFLAG Output options |
---|
1583 | OPOST Postprocess output (not set = raw output) |
---|
1584 | ONLCR Map NL to CR-NL |
---|
1585 | |
---|
1586 | ONCLR ant others needs OPOST to be enabled |
---|
1587 | */ |
---|
1588 | |
---|
1589 | /* Raw ouput */ |
---|
1590 | tios.c_oflag &=~ OPOST; |
---|
1591 | |
---|
1592 | /* C_CC Control characters |
---|
1593 | VMIN Minimum number of characters to read |
---|
1594 | VTIME Time to wait for data (tenths of seconds) |
---|
1595 | |
---|
1596 | UNIX serial interface drivers provide the ability to |
---|
1597 | specify character and packet timeouts. Two elements of the |
---|
1598 | c_cc array are used for timeouts: VMIN and VTIME. Timeouts |
---|
1599 | are ignored in canonical input mode or when the NDELAY |
---|
1600 | option is set on the file via open or fcntl. |
---|
1601 | |
---|
1602 | VMIN specifies the minimum number of characters to read. If |
---|
1603 | it is set to 0, then the VTIME value specifies the time to |
---|
1604 | wait for every character read. Note that this does not mean |
---|
1605 | that a read call for N bytes will wait for N characters to |
---|
1606 | come in. Rather, the timeout will apply to the first |
---|
1607 | character and the read call will return the number of |
---|
1608 | characters immediately available (up to the number you |
---|
1609 | request). |
---|
1610 | |
---|
1611 | If VMIN is non-zero, VTIME specifies the time to wait for |
---|
1612 | the first character read. If a character is read within the |
---|
1613 | time given, any read will block (wait) until all VMIN |
---|
1614 | characters are read. That is, once the first character is |
---|
1615 | read, the serial interface driver expects to receive an |
---|
1616 | entire packet of characters (VMIN bytes total). If no |
---|
1617 | character is read within the time allowed, then the call to |
---|
1618 | read returns 0. This method allows you to tell the serial |
---|
1619 | driver you need exactly N bytes and any read call will |
---|
1620 | return 0 or N bytes. However, the timeout only applies to |
---|
1621 | the first character read, so if for some reason the driver |
---|
1622 | misses one character inside the N byte packet then the read |
---|
1623 | call could block forever waiting for additional input |
---|
1624 | characters. |
---|
1625 | |
---|
1626 | VTIME specifies the amount of time to wait for incoming |
---|
1627 | characters in tenths of seconds. If VTIME is set to 0 (the |
---|
1628 | default), reads will block (wait) indefinitely unless the |
---|
1629 | NDELAY option is set on the port with open or fcntl. |
---|
1630 | */ |
---|
1631 | /* Unused because we use open with the NDELAY option */ |
---|
1632 | tios.c_cc[VMIN] = 0; |
---|
1633 | tios.c_cc[VTIME] = 0; |
---|
1634 | |
---|
1635 | if (tcsetattr(mb_param->fd, TCSANOW, &tios) < 0) { |
---|
1636 | perror("tcsetattr\n"); |
---|
1637 | return -1; |
---|
1638 | } |
---|
1639 | |
---|
1640 | return 0; |
---|
1641 | } |
---|
1642 | |
---|
1643 | /* Establishes a modbus TCP connection with a modbus slave */ |
---|
1644 | static int modbus_connect_tcp(modbus_param_t *mb_param) |
---|
1645 | { |
---|
1646 | int ret; |
---|
1647 | int option; |
---|
1648 | struct sockaddr_in addr; |
---|
1649 | |
---|
1650 | addr.sin_family = AF_INET; |
---|
1651 | addr.sin_port = htons(mb_param->port); |
---|
1652 | addr.sin_addr.s_addr = inet_addr(mb_param->ip); |
---|
1653 | |
---|
1654 | mb_param->fd = socket(AF_INET, SOCK_STREAM, 0); |
---|
1655 | if (mb_param->fd < 0) { |
---|
1656 | return mb_param->fd; |
---|
1657 | } |
---|
1658 | |
---|
1659 | /* Set the TCP no delay flag */ |
---|
1660 | /* SOL_TCP = IPPROTO_TCP */ |
---|
1661 | option = 1; |
---|
1662 | ret = setsockopt(mb_param->fd, IPPROTO_TCP, TCP_NODELAY, |
---|
1663 | (const void *)&option, sizeof(int)); |
---|
1664 | if (ret < 0) { |
---|
1665 | perror("setsockopt"); |
---|
1666 | close(mb_param->fd); |
---|
1667 | return ret; |
---|
1668 | } |
---|
1669 | |
---|
1670 | #ifndef __APPLE__ |
---|
1671 | /* Set the IP low delay option- Not Supported on Mac OS X MJB 02/16/09 */ |
---|
1672 | option = IPTOS_LOWDELAY; |
---|
1673 | ret = setsockopt(mb_param->fd, IPPROTO_TCP, IP_TOS, |
---|
1674 | (const void *)&option, sizeof(int)); |
---|
1675 | if (ret < 0) { |
---|
1676 | perror("setsockopt"); |
---|
1677 | close(mb_param->fd); |
---|
1678 | return ret; |
---|
1679 | } |
---|
1680 | #endif |
---|
1681 | |
---|
1682 | if (mb_param->debug) { |
---|
1683 | printf("Connecting to %s\n", mb_param->ip); |
---|
1684 | } |
---|
1685 | |
---|
1686 | ret = connect(mb_param->fd, (struct sockaddr *)&addr, |
---|
1687 | sizeof(struct sockaddr_in)); |
---|
1688 | if (ret < 0) { |
---|
1689 | perror("connect"); |
---|
1690 | close(mb_param->fd); |
---|
1691 | return ret; |
---|
1692 | } |
---|
1693 | |
---|
1694 | return 0; |
---|
1695 | } |
---|
1696 | |
---|
1697 | /* Establishes a modbus connexion. |
---|
1698 | Returns -1 if an error occured. */ |
---|
1699 | int modbus_connect(modbus_param_t *mb_param) |
---|
1700 | { |
---|
1701 | int ret; |
---|
1702 | |
---|
1703 | if (mb_param->type_com == RTU) |
---|
1704 | ret = modbus_connect_rtu(mb_param); |
---|
1705 | else |
---|
1706 | ret = modbus_connect_tcp(mb_param); |
---|
1707 | |
---|
1708 | return ret; |
---|
1709 | } |
---|
1710 | |
---|
1711 | /* Closes the file descriptor in RTU mode */ |
---|
1712 | static void modbus_close_rtu(modbus_param_t *mb_param) |
---|
1713 | { |
---|
1714 | if (tcsetattr(mb_param->fd, TCSANOW, &(mb_param->old_tios)) < 0) |
---|
1715 | perror("tcsetattr"); |
---|
1716 | |
---|
1717 | close(mb_param->fd); |
---|
1718 | } |
---|
1719 | |
---|
1720 | /* Closes the network connection and socket in TCP mode */ |
---|
1721 | static void modbus_close_tcp(modbus_param_t *mb_param) |
---|
1722 | { |
---|
1723 | shutdown(mb_param->fd, SHUT_RDWR); |
---|
1724 | close(mb_param->fd); |
---|
1725 | } |
---|
1726 | |
---|
1727 | /* Closes a modbus connection */ |
---|
1728 | void modbus_close(modbus_param_t *mb_param) |
---|
1729 | { |
---|
1730 | if (mb_param->type_com == RTU) |
---|
1731 | modbus_close_rtu(mb_param); |
---|
1732 | else |
---|
1733 | modbus_close_tcp(mb_param); |
---|
1734 | } |
---|
1735 | |
---|
1736 | /* Activates the debug messages */ |
---|
1737 | void modbus_set_debug(modbus_param_t *mb_param, int boolean) |
---|
1738 | { |
---|
1739 | mb_param->debug = boolean; |
---|
1740 | } |
---|
1741 | |
---|
1742 | |
---|
1743 | // Activates saving raw query and responses |
---|
1744 | void modbus_set_raw_data_save(modbus_param_t *mb_param, int boolean) |
---|
1745 | { |
---|
1746 | mb_param->saveRawData=boolean; |
---|
1747 | } |
---|
1748 | |
---|
1749 | // Returns a raw query |
---|
1750 | int modbus_last_raw_query(modbus_param_t *mb_param, uint8_t *rawQuery) |
---|
1751 | { |
---|
1752 | int i; |
---|
1753 | if(mb_param->rawQuery!=NULL) |
---|
1754 | { |
---|
1755 | for (i = 0; i < MIN_QUERY_LENGTH; i++) |
---|
1756 | rawQuery[i]=mb_param->rawQuery[i]; |
---|
1757 | return TRUE; |
---|
1758 | } |
---|
1759 | return FALSE; |
---|
1760 | } |
---|
1761 | |
---|
1762 | // Returns a raw response |
---|
1763 | int modbus_last_raw_response(modbus_param_t *mb_param, uint8_t *rawResponse) |
---|
1764 | { |
---|
1765 | int i; |
---|
1766 | if(mb_param->rawResponse!=NULL) |
---|
1767 | { |
---|
1768 | for (i = 0; i < mb_param->rawResponseLength; i++) |
---|
1769 | rawResponse[i]=mb_param->rawResponse[i]; |
---|
1770 | return TRUE; |
---|
1771 | } |
---|
1772 | return FALSE; |
---|
1773 | } |
---|
1774 | |
---|
1775 | int modbus_last_raw_query_length(modbus_param_t *mb_param) |
---|
1776 | { |
---|
1777 | return(mb_param->rawQueryLength); |
---|
1778 | } |
---|
1779 | |
---|
1780 | int modbus_last_raw_response_length(modbus_param_t *mb_param) |
---|
1781 | { |
---|
1782 | return(mb_param->rawResponseLength); |
---|
1783 | } |
---|
1784 | |
---|
1785 | |
---|
1786 | /* Allocates 4 arrays to store coils, input status, input registers and |
---|
1787 | holding registers. The pointers are stored in modbus_mapping structure. |
---|
1788 | |
---|
1789 | Returns: TRUE if ok, FALSE on failure |
---|
1790 | */ |
---|
1791 | int modbus_mapping_new(modbus_mapping_t *mb_mapping, |
---|
1792 | int nb_coil_status, int nb_input_status, |
---|
1793 | int nb_holding_registers, int nb_input_registers) |
---|
1794 | { |
---|
1795 | /* 0X */ |
---|
1796 | mb_mapping->nb_coil_status = nb_coil_status; |
---|
1797 | mb_mapping->tab_coil_status = |
---|
1798 | (uint8_t *) malloc(nb_coil_status * sizeof(uint8_t)); |
---|
1799 | memset(mb_mapping->tab_coil_status, 0, |
---|
1800 | nb_coil_status * sizeof(uint8_t)); |
---|
1801 | if (mb_mapping->tab_coil_status == NULL) |
---|
1802 | return FALSE; |
---|
1803 | |
---|
1804 | /* 1X */ |
---|
1805 | mb_mapping->nb_input_status = nb_input_status; |
---|
1806 | mb_mapping->tab_input_status = |
---|
1807 | (uint8_t *) malloc(nb_input_status * sizeof(uint8_t)); |
---|
1808 | memset(mb_mapping->tab_input_status, 0, |
---|
1809 | nb_input_status * sizeof(uint8_t)); |
---|
1810 | if (mb_mapping->tab_input_status == NULL) { |
---|
1811 | free(mb_mapping->tab_coil_status); |
---|
1812 | return FALSE; |
---|
1813 | } |
---|
1814 | |
---|
1815 | /* 4X */ |
---|
1816 | mb_mapping->nb_holding_registers = nb_holding_registers; |
---|
1817 | mb_mapping->tab_holding_registers = |
---|
1818 | (uint16_t *) malloc(nb_holding_registers * sizeof(uint16_t)); |
---|
1819 | memset(mb_mapping->tab_holding_registers, 0, |
---|
1820 | nb_holding_registers * sizeof(uint16_t)); |
---|
1821 | if (mb_mapping->tab_holding_registers == NULL) { |
---|
1822 | free(mb_mapping->tab_coil_status); |
---|
1823 | free(mb_mapping->tab_input_status); |
---|
1824 | return FALSE; |
---|
1825 | } |
---|
1826 | |
---|
1827 | /* 3X */ |
---|
1828 | mb_mapping->nb_input_registers = nb_input_registers; |
---|
1829 | mb_mapping->tab_input_registers = |
---|
1830 | (uint16_t *) malloc(nb_input_registers * sizeof(uint16_t)); |
---|
1831 | memset(mb_mapping->tab_input_registers, 0, |
---|
1832 | nb_input_registers * sizeof(uint16_t)); |
---|
1833 | if (mb_mapping->tab_input_registers == NULL) { |
---|
1834 | free(mb_mapping->tab_coil_status); |
---|
1835 | free(mb_mapping->tab_input_status); |
---|
1836 | free(mb_mapping->tab_holding_registers); |
---|
1837 | return FALSE; |
---|
1838 | } |
---|
1839 | |
---|
1840 | return TRUE; |
---|
1841 | } |
---|
1842 | |
---|
1843 | /* Frees the 4 arrays */ |
---|
1844 | void modbus_mapping_free(modbus_mapping_t *mb_mapping) |
---|
1845 | { |
---|
1846 | free(mb_mapping->tab_coil_status); |
---|
1847 | free(mb_mapping->tab_input_status); |
---|
1848 | free(mb_mapping->tab_holding_registers); |
---|
1849 | free(mb_mapping->tab_input_registers); |
---|
1850 | } |
---|
1851 | |
---|
1852 | /* Listens for any query from a modbus master in TCP */ |
---|
1853 | int modbus_init_listen_tcp(modbus_param_t *mb_param) |
---|
1854 | { |
---|
1855 | int ret; |
---|
1856 | int new_socket; |
---|
1857 | struct sockaddr_in addr; |
---|
1858 | socklen_t addrlen; |
---|
1859 | |
---|
1860 | addr.sin_family = AF_INET; |
---|
1861 | /* If the modbus port is < to 1024, we need the setuid root. */ |
---|
1862 | addr.sin_port = htons(mb_param->port); |
---|
1863 | addr.sin_addr.s_addr = INADDR_ANY; |
---|
1864 | memset(&(addr.sin_zero), '\0', 8); |
---|
1865 | |
---|
1866 | new_socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); |
---|
1867 | if (new_socket < 0) { |
---|
1868 | perror("socket"); |
---|
1869 | exit(1); |
---|
1870 | } else { |
---|
1871 | printf("Socket OK\n"); |
---|
1872 | } |
---|
1873 | |
---|
1874 | ret = bind(new_socket, (struct sockaddr *)&addr, |
---|
1875 | sizeof(struct sockaddr_in)); |
---|
1876 | if (ret < 0) { |
---|
1877 | perror("bind"); |
---|
1878 | close(new_socket); |
---|
1879 | exit(1); |
---|
1880 | } else { |
---|
1881 | printf("Bind OK\n"); |
---|
1882 | } |
---|
1883 | |
---|
1884 | ret = listen(new_socket, 1); |
---|
1885 | if (ret != 0) { |
---|
1886 | perror("listen"); |
---|
1887 | close(new_socket); |
---|
1888 | exit(1); |
---|
1889 | } else { |
---|
1890 | printf("Listen OK\n"); |
---|
1891 | } |
---|
1892 | |
---|
1893 | addrlen = sizeof(struct sockaddr_in); |
---|
1894 | mb_param->fd = accept(new_socket, (struct sockaddr *)&addr, &addrlen); |
---|
1895 | if (ret < 0) { |
---|
1896 | perror("accept"); |
---|
1897 | close(new_socket); |
---|
1898 | new_socket = 0; |
---|
1899 | exit(1); |
---|
1900 | } else { |
---|
1901 | printf("The client %s is connected\n", |
---|
1902 | inet_ntoa(addr.sin_addr)); |
---|
1903 | } |
---|
1904 | |
---|
1905 | return new_socket; |
---|
1906 | } |
---|
1907 | |
---|
1908 | /** Utils **/ |
---|
1909 | |
---|
1910 | /* Sets many input/coil status from a single byte value (all 8 bits of |
---|
1911 | the byte value are setted) */ |
---|
1912 | void set_bits_from_byte(uint8_t *dest, int address, const uint8_t value) |
---|
1913 | { |
---|
1914 | int i; |
---|
1915 | |
---|
1916 | for (i=0; i<8; i++) { |
---|
1917 | dest[address+i] = (value & (1 << i)) ? ON : OFF; |
---|
1918 | } |
---|
1919 | } |
---|
1920 | |
---|
1921 | /* Sets many input/coil status from a table of bytes (only the bits |
---|
1922 | between address and address + nb_bits are setted) */ |
---|
1923 | void set_bits_from_bytes(uint8_t *dest, int address, int nb_bits, |
---|
1924 | const uint8_t tab_byte[]) |
---|
1925 | { |
---|
1926 | int i; |
---|
1927 | int shift = 0; |
---|
1928 | |
---|
1929 | for (i = address; i < address + nb_bits; i++) { |
---|
1930 | dest[i] = tab_byte[(i - address) / 8] & (1 << shift) ? ON : OFF; |
---|
1931 | /* gcc doesn't like: shift = (++shift) % 8; */ |
---|
1932 | shift++; |
---|
1933 | shift %= 8; |
---|
1934 | } |
---|
1935 | } |
---|
1936 | |
---|
1937 | /* Gets the byte value from many input/coil status. |
---|
1938 | To obtain a full byte, set nb_bits to 8. */ |
---|
1939 | uint8_t get_byte_from_bits(const uint8_t *src, int address, int nb_bits) |
---|
1940 | { |
---|
1941 | int i; |
---|
1942 | uint8_t value = 0; |
---|
1943 | |
---|
1944 | if (nb_bits > 8) { |
---|
1945 | printf("Error: nb_bits is too big\n"); |
---|
1946 | nb_bits = 8; |
---|
1947 | } |
---|
1948 | |
---|
1949 | for (i=0; i < nb_bits; i++) { |
---|
1950 | value |= (src[address+i] << i); |
---|
1951 | } |
---|
1952 | |
---|
1953 | return value; |
---|
1954 | } |
---|