Christian Gulde / ModBusTCP

ModBus TCP Implementation

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ModBus_util.cpp@4:41ee166a0e6c, 2017-06-30 (annotated)

Committer:
gulchi
Date:
Fri Jun 30 10:40:06 2017 +0000
Revision:
4:41ee166a0e6c
Parent:
3:ebea8e061ae6 
updated license

Who changed what in which revision?

UserRevisionLine numberNew contents of line
gulchi 3:ebea8e061ae6 1 /* Copyright (C) 2013 Hiroshi Suga, MIT License
gulchi 3:ebea8e061ae6 2 *
gulchi 3:ebea8e061ae6 3 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
gulchi 3:ebea8e061ae6 4 * and associated documentation files (the "Software"), to deal in the Software without restriction,
gulchi 3:ebea8e061ae6 5 * including without limitation the rights to use, copy, modify, merge, publish, distribute,
gulchi 3:ebea8e061ae6 6 * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
gulchi 3:ebea8e061ae6 7 * furnished to do so, subject to the following conditions:
gulchi 3:ebea8e061ae6 8 *
gulchi 3:ebea8e061ae6 9 * The above copyright notice and this permission notice shall be included in all copies or
gulchi 3:ebea8e061ae6 10 * substantial portions of the Software.
gulchi 3:ebea8e061ae6 11 *
gulchi 3:ebea8e061ae6 12 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
gulchi 3:ebea8e061ae6 13 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
gulchi 3:ebea8e061ae6 14 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
gulchi 3:ebea8e061ae6 15 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
gulchi 3:ebea8e061ae6 16 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
gulchi 3:ebea8e061ae6 17 */
gulchi 3:ebea8e061ae6 18
gulchi 3:ebea8e061ae6 19 #include "ModBus-TCP.h"
gulchi 3:ebea8e061ae6 20 #include <ctype.h>
gulchi 3:ebea8e061ae6 21 #include <stdlib.h>
gulchi 3:ebea8e061ae6 22 #include <string.h>
gulchi 3:ebea8e061ae6 23
gulchi 3:ebea8e061ae6 24
gulchi 3:ebea8e061ae6 25
gulchi 3:ebea8e061ae6 26 int Modbus::getHandler (int startRegister) {
gulchi 3:ebea8e061ae6 27 int i;
gulchi 3:ebea8e061ae6 28
gulchi 3:ebea8e061ae6 29 for (i = 0; i < _handler_count; i ++) {
gulchi 3:ebea8e061ae6 30 if (_handler[i].startRegister == startRegister) {
gulchi 3:ebea8e061ae6 31 // found
gulchi 3:ebea8e061ae6 32 return i;
gulchi 3:ebea8e061ae6 33 }
gulchi 3:ebea8e061ae6 34 }
gulchi 3:ebea8e061ae6 35 return -1;
gulchi 3:ebea8e061ae6 36 }
gulchi 3:ebea8e061ae6 37
gulchi 3:ebea8e061ae6 38
gulchi 3:ebea8e061ae6 39 int Modbus::attachRead (void (*funcCgi)(int, unsigned short, unsigned short), int startRegister) {
gulchi 3:ebea8e061ae6 40 if (_handler_count < MODBUS_MAX_HANDLES) {
gulchi 3:ebea8e061ae6 41 _handler[_handler_count].startRegister = startRegister;
gulchi 3:ebea8e061ae6 42 _handler[_handler_count].funcCgiRead = funcCgi;
gulchi 3:ebea8e061ae6 43 _handler_count ++;
gulchi 3:ebea8e061ae6 44 return 0;
gulchi 3:ebea8e061ae6 45 } else {
gulchi 3:ebea8e061ae6 46 return -1;
gulchi 3:ebea8e061ae6 47 }
gulchi 3:ebea8e061ae6 48 }
gulchi 3:ebea8e061ae6 49
gulchi 3:ebea8e061ae6 50
gulchi 3:ebea8e061ae6 51 int Modbus::send (int id, unsigned short buffer[], int len) {
gulchi 3:ebea8e061ae6 52
gulchi 3:ebea8e061ae6 53 char out[MODBUS_BUF_SIZE];
gulchi 3:ebea8e061ae6 54
gulchi 3:ebea8e061ae6 55
gulchi 3:ebea8e061ae6 56 // Build MBAP Header
gulchi 3:ebea8e061ae6 57 //Transaction Number :: Copy from Org message
gulchi 3:ebea8e061ae6 58 out[0] = _state[id].start_message[0];
gulchi 3:ebea8e061ae6 59 out[1] = _state[id].start_message[1];
gulchi 3:ebea8e061ae6 60
gulchi 3:ebea8e061ae6 61 //Protcoll Identifier :: Always 0x0000
gulchi 3:ebea8e061ae6 62 out[2] = 0x00;
gulchi 3:ebea8e061ae6 63 out[3] = 0x00;
gulchi 3:ebea8e061ae6 64
gulchi 3:ebea8e061ae6 65 // Length (bytes to follow after length bytes) of TCP Frame
gulchi 3:ebea8e061ae6 66 out[4] = (char)(((len*2)+3)>> 8);
gulchi 3:ebea8e061ae6 67 out[5] = (char)(((len*2)+3) & 0x00ff);
gulchi 3:ebea8e061ae6 68
gulchi 3:ebea8e061ae6 69 //unit identifier (normally 0xff, but 0x00 is allowed
gulchi 3:ebea8e061ae6 70 out[6] = 0xff;
gulchi 3:ebea8e061ae6 71
gulchi 3:ebea8e061ae6 72 //MBAP Header build finished
gulchi 3:ebea8e061ae6 73
gulchi 3:ebea8e061ae6 74 // Now the ModBus response
gulchi 3:ebea8e061ae6 75 //Function code :: Copy from org message
gulchi 3:ebea8e061ae6 76 out[7] = _state[id].start_message[7];
gulchi 3:ebea8e061ae6 77
gulchi 3:ebea8e061ae6 78 //Byte count of Modbus response
gulchi 3:ebea8e061ae6 79 out[8] = len*2;
gulchi 3:ebea8e061ae6 80
gulchi 3:ebea8e061ae6 81 for(int i=0; i<len; i++) {
gulchi 3:ebea8e061ae6 82 out[(i*2)+9] = (char)(buffer[i] >> 8);
gulchi 3:ebea8e061ae6 83 out[(i*2)+10] = (char)(buffer[i] & 0x00ff);
gulchi 3:ebea8e061ae6 84 }
gulchi 3:ebea8e061ae6 85
gulchi 3:ebea8e061ae6 86
gulchi 3:ebea8e061ae6 87
gulchi 3:ebea8e061ae6 88 DBG("sending anser on child %i", id);
gulchi 3:ebea8e061ae6 89 return _state[id].client->send(out, (len*2)+9);
gulchi 3:ebea8e061ae6 90 }
gulchi 3:ebea8e061ae6 91
gulchi 3:ebea8e061ae6 92 int Modbus::sendToClient(int id, char buffer[], unsigned short len) {
gulchi 3:ebea8e061ae6 93 return _state[id].client->send(buffer, len);
gulchi 3:ebea8e061ae6 94 }
gulchi 3:ebea8e061ae6 95
gulchi 3:ebea8e061ae6 96
gulchi 3:ebea8e061ae6 97 int Modbus::from_hex (int ch) {
gulchi 3:ebea8e061ae6 98 return isdigit(ch) ? ch - '0' : tolower(ch) - 'a' + 10;
gulchi 3:ebea8e061ae6 99 }
gulchi 3:ebea8e061ae6 100
gulchi 3:ebea8e061ae6 101 int Modbus::to_hex (int code) {
gulchi 3:ebea8e061ae6 102 static char hex[] = "0123456789abcdef";
gulchi 3:ebea8e061ae6 103 return hex[code & 15];
gulchi 3:ebea8e061ae6 104 }