The goal of this software is to automatically generate C/C++ code which reads and writes GOOSE and Sampled Value packets. Any valid IEC 61850 Substation Configuration Description (SCD) file, describing GOOSE and/or SV communications, can be used as the input. The output code is lightweight and platform-independent, so it can run on a variety of devices, including low-cost microcontrollers. It\'s ideal for rapid-prototyping new protection and control systems that require communications. This mbed project is a simple example of this functionality. Other code: https://github.com/stevenblair/rapid61850 Project homepage: http://personal.strath.ac.uk/steven.m.blair/
decodePacket.c
- Committer:
- sblair
- Date:
- 2011-10-07
- Revision:
- 1:9399d44c2b1a
- Parent:
- 0:230c10b228ea
File content as of revision 1:9399d44c2b1a:
/** * Rapid-prototyping protection schemes with IEC 61850 * * Copyright (c) 2011 Steven Blair * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include "decodePacket.h" //#include "svEncodeBasic.h" // returns size of length field, from first byte int getLengthFieldSize(unsigned char byte) { if (byte <= 126) { return 1; } else { return 1 + (byte & 0x7F); } } //TODO check this works for all inputs, e.g., buf[1] = 0xFF int decodeLength(unsigned char *buf) { if (buf[0] <= 126) { return buf[0]; } else { int bytes = (buf[0] & 0x7F); if (bytes == 1) { return buf[1]; } else if (bytes == 2) { // assumes max length of 2^15 return ((buf[1] & 0xFF) << 8) | (buf[2] & 0xFF); } } return 0; }